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Active 2013 Hurricane Season Predicted

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Tornadoes Were Just the Beginning. This Hurricane Season Is Going to be Stormy

By May 24, 20136 Comments
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Photo by NASA via Getty ImagesA satellite image of Hurricane Sandy as it approached the East Coast last year

The residents of Moore, Oklahoma are still cleaning up from the EF5 tornado that tore through their town on May 20. 24 people died in the twisters, and thousands of homes and buildings were damaged or destroyed. The total bill may come in at over $2 billion, which would make the Moore tornado the most expensive in American history.

So this may not be the best time, but the Moore tornado almost surely won’t be the last billion-dollar weather the U.S. faces in 2013. On Thursday the National Oceanic and Atmospheric Administration (NOAA) released its annual outlook on the summer Atlantic hurricane season—and it is not good. Technically it will be “active or extremely active,” which is fine if you’re talking about a workout session, and less good if you’re projecting how many potentially devastating tropical storms will hit the U.S. mainland.

Altogether NOAA predicts a 70% likelihood that 13 to 20 named storms—which have winds that sustain at 39 mph or higher—will occur, of which 7 to 11 could become hurricanes (winds higher than 74 mph). Of those three to six may become major hurricanes, which means Category 3 to 5, with winds above 11 mph. That’s all well above the average for an Atlantic hurricane season, which lasts from June 1 to the end of November.

Why will this summer potentially be so stormy? For one, an atmospheric climate pattern, including a strong African monsoon, that’s been ongoing since 1995 will help supercharge the atmosphere for tropical storms. Warmer-than-average water temperatures in the tropical Atlantic and the Caribbean Sea will lead to more of the wet, hot air that provides the fuel for hurricanes. And there is no El Nino—the alternating climate pattern that means unusually warm sea temperatures—which would usually suppress the formation of hurricanes.

It’s important to remember that NOAA is only predicting whether or not hurricanes and tropical storms will develop—not whether they will make landfall like Superstorm Sandy did last fall. Only three of the 19 named storms that formed in the Atlantic last year made enough of an impact on the U.S. to cause any real damage. Most storms form in the Atlantic and never leave. It’s not just the strength of a storm that makes it dangerous—it’s location.

Superstorm Sandy made that clear. By the time storm made landfall on the East Coast, it had actually weakened to the point that it was barely a hurricane at all, though it was an unusually massive and wet storm. Had it spun back out to sea, we never would have remembered its name. Instead, though, Sandy tore through the most populated and expensive property in the U.S., flooding parts of New York City and causing some $65 billion in damage. We can only imagine what kind of destruction it would have caused had Sandy been an even stronger storm.

(VIDEO: The 2012 Atlantic Hurricane Season in 4.5 Minutes)

There’s no way of knowing how many of the storms to come this summer will indeed make landfall, but it stands to reason that the more storms that form, the greater the chance one will eventually end up in our backyard. According to NOAA, billion-dollar disasters are increasing in the U.S. at a rate of about 4.8% a year—there were 11 just last year. That’s mostly a result of economic growth—as the country gets richer, even with inflation, any weather disaster that disrupt the economy will cost more. But climate change is likely playing a role as well—in the case of hurricanes, warming temperatures seem to make storms stronger, and rising sea levels increase the threat of coastal flooding.

In any case, the growing danger from extreme weather just underlines the need to invest in forecasting, preparation and adaptation, as acting NOAA Administrator Kathryn Sullivan said:

With the devastation of Sandy fresh in our minds, and another active season predicted, everyone at NOAA is committed to providing life-saving forecasts in the face of these storms and ensuring that Americans are prepared and ready ahead of time.” said Kathryn Sullivan, Ph.D., NOAA acting administrator. “As we saw first-hand with Sandy, it’s important to remember that tropical storm and hurricane impacts are not limited to the coastline. Strong winds, torrential rain, flooding, and tornadoes often threaten inland areas far from where the storm first makes landfall.

Of course, if you really want to worry, remember that last year NOAA predict that the Atlantic hurricane season would be just a little above normal. It ended up being considerably more active. But there’s one thing we can be sure of—there won’t be another Hurricane Sandy. That name has been retired.

Read more: http://science.time.com/2013/05/24/tornadoes-were-just-the-beginning-this-hurricane-season-is-going-to-be-stormy/#ixzz2UDvCa8hJ

Jeff Masters on Tornadoes & Typhoons

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After going twelve months with a record-low tornado death toll of just seven people, last night we received a jolting reminder that tornadoes typically kill a lot more people than that in the U.S. A deadly tornado swept through Granbury, Texas near 8 pm CDT, killing six and injuring up to 100. The weather system that spawned the Granby tornado also unleashed a mile-wide twister that hit Cleburne, about 25 miles southeast of Granbury. Damage was heavy in Cleburne and a state of emergency declared, but only seven minor injuries were reported. A third tornado hit the small town of Millsap, about 40 miles west of Fort Worth, causing roof damage a destroying a barn, but caused no injuries. Preliminary figures indicate that a total ten tornadoes touched down in Texas last night, and NWS damage survey teams are out today to determine the exact total and how strong they were. The National Weather Service out of Fort Worth has issued a preliminary rating of EF-4 to the Granbury tornado, making it the first tornado stronger than EF-0 reported in May 2013. The storms also dumped softball-sized hail up to 4″ in diameter in Mineral Wells, TX.

Video 1. The Granbury, Texas tornado of May 15, 2013.

Thursday’s tornado was the deadliest U.S. tornado in over a year. The last time six people died in a U.S. tornado was on April 14, 2012, during an EF-3 tornado that hit Woodward, Oklahoma. The last Texas tornado that was deadlier occurred on April 24, 2007 in Maverick County, when an EF-3 tornado hit Eagle Pass, Texas, killing seven. Texas has had one other tornado death in 2013, from a twister that hit on February 21, 2013, in Sabine County. The region of Texas hit by last night’s tornadoes has few basements, which may have contributed to the death toll. According to underground member Seattleite, “In this part of Texas basements are very uncommon. The reason is due to the soil, it is basically clay. It contracts and expands with temperature and moisture levels on the order of a foot or more in a typical year. The pressure from this can cause basement walls to cave. They can be built, but it costs at least an extra $20,000+, as they surround the basement with a sand-like barrier to handle the changes in the ground.”


Figure 1. Softball, anyone? One of the 4″ hailstones that fell near Mineral Wells, Texas on May 15, 2013. Image from Patrick Vondra via Twitter.

Is the 2012 – 2013 tornado drought over?
Thanks to the cold spring in the Midwest during 2013, and the 2012 Midwest drought, the 197 EF-1 and stronger tornadoes that occurred during May 2012 – April 2012 was an all-time minimum for any twelve-month period since at least 1954, wrote tornado researcher Harold Brooks at the U.S. Severe Weather Blog (previous minimum: 247 tornadoes from June 1991-May 1992.) The death toll of just seven was also a record low for any twelve-month period since 1950. Amazingly, this tornado drought occurred less than two years after the record maximum: 1050 EF-1 and stronger tornadoes from June 2010 – May 2011. The extraordinary contrast underscores the crazy fluctuations we’ve seen in Northern Hemisphere jet stream patterns during the past three years. Call it “Weather Whiplash” of the tornado variety. A blog post by meteorologist Patrick Marsh of NOAA’s Storm Prediction Center argues that the record 12-month tornado maximum of 1050 EF-1 and stronger tornadoes from June 2010 – May 2011 was a 1-in-62,500 year event. The record 12-month minimum of 197 EF-1 and stronger tornadoes that occurred from May 2012 – April 2013 was a 1-in-3000 to 1-in-4000 year event. In Marsh’s words: “Anyway you look at it, the recent tornado “surplus” and the current tornado “drought” is extremely rare. The fact that we had both of them in the span of a few years is even more so!”

Our tornado drought may be at its end, as the latest forecasts from NOAA’s Storm Prediction Center call for an active severe weather pattern Saturday – Monday. The current forecast calls for just a “Slight Risk” on Saturday over the Northern Plains, but the threat will grow on Sunday and Monday as a powerful spring weather system gathers strength over the center of the country.

Saturday’s main threat areas: SD to NE, and northern KS
Sunday : IA, parts of MO/KS, to central/eastern OK
Monday : IL/MO to OK/TX border


Figure 2. MODIS image of Tropical Cyclone Mahasen taken at 06:50 UTC Thursday May 16, 2013. Mahasen made landfall about two hour prior to this image as a tropical storm with 50 mph winds. Image credit: NASA.

Tropical Storm Mahasen hits Bangladesh
Tropical Storm Mahasen hit the Bangladesh coast near 08 UTC Thursday, May 16 near a place called Feni north of Chittagong. Mahasen was a tropical storm with top winds of 50 mph at landfall. Satellite observations suggest that the storm was becoming much more organized just before landfall, and it is fortunate that the storm ran out of time to intensify when it did. Mahasen likely brought a storm surge of up to a meter (3.3 feet) to the coast of Bangladesh, but it is the storm’s rains that are causing the main problems. Satellite rainfall forecasts made at landfall show that Mahasen could dump up to 20 inches of rain along a swath through Bangladesh and into Northeastern India. These rains will be capable of causing destructive flooding, and ten deaths have already been reported in Bangladesh from the storm. At least eight people have been killed in Sri Lanka due to landslides triggered by Mahasen’s heavy rains, and a boat carrying refugees capsized on Monday, killing eight and leaving 50 missing.

First tropical storm of the year, Alvin, forms in the Eastern Pacific
The official start of hurricane season in the Eastern Pacific is Wednesday, May 15, and Mother Nature emphatically agreed, bringing us the first named storm of the year, Tropical Storm Alvin. With wind shear a moderate 10 – 20 knots and the storm currently struggling to hold itself together, it currently appears unlikely that we will see a Hurricane Alvin. The storm is moving west-northwest into the Central Pacific, and is not a threat to any land areas.

from:    http://www.wunderground.com/blog/JeffMasters/show.html

Overview of the 2012 Hurricane Season fr/Jeff Masters

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The bizarrely active hurricane season of 2012 draws to a close
Published: 4:50 PM GMT on November 30, 2012
The long and highly destructive hurricane season of 2012 has finally drawn to a close. The hurricane season of 2012 will long be remembered for spawning Hurricane Sandy–a freakish storm that was the largest, most powerful, and second most destructive Atlantic hurricane on record. But this year’s hurricane season had a number of unique attributes, making it one of the most bizarre seasons I’ve witnessed. Despite featuring a remarkable nineteen named storms–tied for the third highest total since record keeping began in 1851–this year’s hurricane season had just one major hurricane. That storm was Hurricane Michael, which stayed at Category 3 strength for a scant six hours. This is the least number of major hurricanes in a season since the El Niño year of 1997, which had only Category 3 Hurricane Erika. There were no Category 4 or 5 hurricanes in 2012, for just the 3rd time since the active hurricane period we are in began in 1995. The only two other years since 1995 without a Category 4 or stronger hurricane were the El Niño years of 2006 and 1997. Both of those seasons had around half the number of named storms of 2012–nine in 2006, and eight in 1997. The relative lack of strong storms in 2012 helped keep the Accumulated Cyclone Energy (ACE) down to 128, about 30% above average.


Figure 1. Hurricane Sandy at 10:10 am EDT October 28, 2012. Image credit: NASA/GSFC.

A near-average year for number of tropical cyclones hitting the U.S.
Since the active hurricane period we’ve been in began in 1995, the U.S. has averaged getting hit by 4 named storms per year, with an average of 1.7 of these being hurricanes, and 0.6 being major Category 3 and stronger hurricanes. This year, we were hit by 3 named storms (Beryl, Debby, and Isaac). One of these was a hurricane (Isaac). Sandy didn’t count as a hurricane strike on the U.S., since it transitioned to an extratropical cyclone a few hours before landfall. No major hurricanes hit the U.S., making 2012 the 7th consecutive year without a major hurricane strike. The only other time we’ve had a streak that long occurred between 1861 – 1868, during the decade of the Civil War.


Figure 2. Vertical instability over the tropical Atlantic in 2004 – 2012 (blue line) compared to average (black line.) The instability is plotted in °C, as a difference in temperature from near the surface to the upper atmosphere (note that the same scale is not used in all the plots, making the black climatological line appear different, when it is really the same for each plot.) Thunderstorms grow much more readily when vertical instability is high. Instability was near average during the August – October peak of hurricane season in 2004 – 2009, but was much lower than average during the hurricane seasons of 2010 – 2012. There was an unusual amount of dry, sinking air in the tropical Atlantic during 2010 – 2012, and the resulting low atmospheric instability reduced the proportion of tropical storms that have intensified into hurricanes. Vertical instability from 2004 – 2011 is taken from NOAA/RAMMB and for 2012 from NOAA/SSD.

Unusually stable air over the Tropical Atlantic in 2012
For the third consecutive hurricane season, 2012 featured an unusual amount of dry, sinking air over the tropical Atlantic and Caribbean Sea. Due to warmer-than-average sea surface temperatures and an active African Monsoon that generated plenty of African waves, a remarkably high number of tropical storms managed to form, but the unusually stable air in the hurricane genesis regions made it difficult for the storms to become strong. When we did see storms undergo significant intensification, it tended to occur outside of the tropics, north of 25°N, where there was not as much dry, sinking air (Sandy’s intensification as it approached landfall in Cuba was an exception to this rule.) If we look at the last nine hurricane seasons (Figure 2), we can see that the hurricane seasons of 2010, 2011, and 2012 all featured similar levels of highly stable air over the tropical Atlantic. This is in marked contrast to what occurred the previous six years. The past three seasons all featured a near-record number of named storms (nineteen each year), but an unusually low ratio of strong hurricanes. Steering patterns the past three years also acted to keep most of the storms out to sea. Is this strange pattern something we’ll see more of, due to climate change? Or is it mostly due to natural cycles in hurricane activity? I don’t have any answers at this point, but the past three hurricane seasons have definitely been highly unusual in a historical context. I expect the steering currents to shift and bring more landfalling hurricanes to the U.S. at some point this decade, though.


Figure 3. Sea water floods the Ground Zero construction site at the World Trade Center, Monday, Oct. 29, 2012, in New York City. Image credit: AP.

Most notable events of the Hurricane Season of 2012
Hurricane Sandy was truly astounding in its size and power. At its peak size, twenty hours before landfall, Sandy had tropical storm-force winds that covered an area nearly one-fifth the area of the contiguous United States. Since detailed records of hurricane size began in 1988, only one tropical storm (Olga of 2001) has had a larger area of tropical storm-force winds, and no hurricanes has. Sandy’s area of ocean with twelve-foot seas peaked at 1.4 million square miles–nearly one-half the area of the contiguous United States, or 1% of Earth’s total ocean area. Most incredibly, ten hours before landfall (9:30 am EDT October 30), the total energy of Sandy’s winds of tropical storm-force and higher peaked at 329 terajoules–the highest value for any Atlantic hurricane since at least 1969. This is 2.7 times higher than Katrina’s peak energy, and is equivalent to five Hiroshima-sized atomic bombs. At landfall, Sandy’s tropical storm-force winds spanned 943 miles of the the U.S. coast. No hurricane on record has been wider; the previous record holder was Hurricane Igor of 2010, which was 863 miles in diameter. Sandy’s huge size prompted high wind warnings to be posted from Chicago to Eastern Maine, and from Michigan’s Upper Peninsula to Florida’s Lake Okeechobee–an area home to 120 million people. Sandy’s winds simultaneously caused damage to buildings on the shores of Lake Michigan at Indiana Dunes National Lake Shore, and toppled power lines in Nova Scotia, Canada–locations 1200 miles apart!


Figure 4. Hurricane Isaac lit up by moonlight as it spins towards the city of New Orleans, LA, on August 26, 2012. The Suomi National Polar-orbiting Partnership (NPP) satellite captured these images with its Visible Infrared Imaging Radiometer Suite (VIIRS). The “day-night band” of VIIRS detects light in a range of wavelengths from green to near-infrared and uses light intensification to enable the detection of dim signals. Image Credit: NASA/NOAA, Earth Observatory.

Hurricane Isaac hit Louisiana as a Category 1 hurricane with 80 mph winds on August 28, but the storm’s massive wind field brought a storm surge characteristic of a Category 2 hurricane to the coast. A storm surge of 11.1 feet was measured at Shell Beach, LA and higher surges were reported in portions of Louisiana. Fortunately, the new $14.5 billion upgrade to the New Orleans levee system kept the city dry. Isaac killed 9 people in the U.S., and 29 in the Caribbean.

Hurricane Ernesto hit Mexico’s Yucatan Peninsula as a Category 1 hurricane with 85 mph winds on August 7. The storm killed 12 and did at least $250 million in damage.

Tropical Storm Debby formed on June 23, the earliest formation date on record for the season’s 4th storm. The previous record was Dennis, on July 5, 2005. Debby killed seven and did over $300 million in damage, but helped relieve drought conditions over Northern Florida and Southern Georgia.

Tropical Storm Beryl, which made landfall on May 28 near Jacksonville Beach, FL with 70 mph winds, was the strongest tropical storm to make landfall in the U.S. prior to June 1. Beryl killed two but did minimal damage.

Nadine lasted for 21.75 days as a named storm, the 5th longest-lasting tropical storm in the Atlantic basin.

It was the 3rd year in a row with 19 named storms.

No named storms existed during the month of July and November, but we still managed big numbers.

Only 7 seasons have had more hurricanes than 2012.

The season had two named storm before the official June 1 start of hurricane season, only the 3rd time that has occurred.

Eight named storms formed in August, which tied 2004 for the most to form in that month.

Typhoon Bopha a threat to the Philippines
In the Western Pacific, where typhoon season commonly brings several storms in December, we have impressive Typhoon Bopha. Bopha is expected to head west-northwest and intensify over the weekend, potentially arriving in the Philippines on Tuesday as a powerful Category 3 typhoon. Bopha formed at an unusually low latitude for a tropical cyclone–near 4°N. Storms forming that close to the Equator don’t get much help from the Earth’s spin to get spinning, and it is rare to see a tropical cyclone forming southwards of 5°N.

The Colorado State University hurricane forecast team, led by Phil Klotzbach and Bill Gray, has a more in-depth summary of the 2012 hurricane season.

Jeff Masters

from:    http://www.wunderground.com/blog/JeffMasters/article.html

Destructive POtential of Hurricane Sandy

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Hurricane Sandy pounding Jamaica, may hit U.S. this weekend; TS Tony forms
Published: 2:21 PM GMT on October 24, 2012

Hurricane warnings are flying for Jamaica and Eastern Cuba, as an intensifying Hurricane Sandy plows north-northeast at 13 mph towards landfall. The Hurricane Hunters are in the storm, and measured surface winds of hurricane strength–75 to 80 mph–in the storm’s northeast quadrant near 9:25 am EDT. Sandy’s pressure at the time of the 9:28 am center fix was 973 mb, and the temperature in the eye had warmed 2°C since the 7:48 am fix, a sign of strengthening. Intermittent rain squalls from Sandy have been affecting Jamaica since Monday night, and Kingston, Jamaica has picked up 2.12″ of rain from Sandy as of 9 am EDT. Winds in Jamaica have been below 20 mph as of 10 am EDT, but will start to rise quickly in the next few hours. The Hurricane Hunters found a large 55 mile-diameter eye that was open to the WNW this morning, and it is likely that Kingston will receive high winds of 55 – 65 mph from the western eyewall, which will cause considerable damage to Jamaica’s capital. The eastern tip of Jamaica will likely see the eye pass overhead, and will receive the strongest winds. The eye is beginning to appear on visible satellite loops, and Sandy is showing an increasing degree of organization as it closes in on Jamaica. Sandy is the tenth hurricane of the 2012 hurricane season, which is now tied for eighth place for most hurricanes in a year since record keeping began in 1851.


Figure 1. Morning microwave satellite image of Tropical Storm Sandy taken at 8:45 am EDT. The large 55-mile diameter eye was just south of Jamaica. Image credit: Navy Research Lab, Monterey.

Near-term forecast for Sandy
Wind shear is forecast to be in the moderate range and ocean temperatures will be a warm 28°C through Thursday morning, which will favor intensification. However, Sandy doesn’t have much time left over water before it encounters the high mountains of Jamaica this afternoon, which should interrupt the intensification process. The strongest Sandy is likely to be at landfall in Jamaica is a 90 mph Category 1 hurricanes. After encountering Jamaica, Sandy won’t have time to re-organize much before making landfall in Eastern Cuba near 10 pm EDT tonight, and the strongest the storm is likely to be then is a 90 mph Category 1. Passage over the rugged terrain of Cuba should weaken Sandy’s winds by 20 – 30 mph, and it will be difficult for the storm to regain all of that lost strength in the face of the high wind shear of 20 – 30 knots it will encounter Thursday and Friday. I expect that Sandy will be a 60 – 70 mph tropical storm as it traverses the Bahamas.


Figure 2. MODIS satellite image of Tropical Storm Sandy taken at 11:45 am EDT Tuesday, October 23, 2012. At the time, Sandy had top winds of 50 mph. Image credit: NASA.

Sandy: a potential billion-dollar storm for the mid-Atlantic and New England
On Friday, a very complicated meteorological situation unfolds, as Sandy interacts with a trough of low pressure approaching the U.S. East Coast and trough of low pressure over the Central Atlantic. The Central Atlantic trough may be strong enough to pull Sandy northeastwards, out to sea, as predicted by the official NHC forecast, and the 06Z GFS, 00Z UKMET, 00Z Canadian, and 06Z HWRF models (00Z is 8 pm EDT, and 06Z is 2 am EDT.) However, an alternative solution, shown by the 00Z ECMWF, 06Z GFDL, and 06Z NOGAPS models, is for Sandy to get caught up by the trough approaching the Eastern U.S., which will inject a large amount of energy into Sandy, converting it to a powerful subtropical storm that hits the mid-Atlantic or New England early next week with a central pressure below 960 mb and sustained winds of 60 – 70 mph. Such a storm would likely cause massive power outages and over a billion dollars in damage, as trees still in leaf take out power grids, and heavy rains and coastal storm surges create damaging flooding. The full moon is on Monday, which means astronomical tides will be at their peak for the month, increasing potential storm surge flooding. A similar meteorological situation occurred in October 1991, when Hurricane Grace became absorbed by a Nor’easter, becoming the so-called “Perfect Storm” that killed 13 people and did over $200 million in damage in the Northeast U.S.


Figure 3. The Wednesday morning 06Z (2 am EDT) run of the GFS model was done 20 times at lower resolution with slightly varying initial conditions of temperature, pressure, and moisture to generate an ensemble of forecast tracks for Sandy (pink lines). These forecasts show substantial uncertainty in Sandy’s path after Friday, with a minority of the forecasts taking Sandy to the northeast, out to sea, and the majority now predicting a landfall in the Northeast or mid-Atlantic states of the U.S. The white line shows the official GFS forecast, run at higher resolution.

When might Sandy arrive in the mid-Atlantic and New England?
The models vary significantly in their predictions of when Sandy might arrive along the U.S. coast. The 06Z NOGAPS model predicts Sandy’s heavy rains will arrive on North Carolina’s Outer Banks on Saturday, then spread into the mid-Atlantic and New England on Sunday. The 00Z ECMWF model predicts that Sandy’s rains won’t affect North Carolina until Sunday, with the storm making landfall in New Jersey on Monday night. The GFDL model is in-between these extremes, taking Sandy ashore in Delaware on Monday morning. The trough of low pressure that Sandy will be interacting with just moved ashore over the Western U.S. this morning, and got sampled by the 12Z (8 am EDT) set of land-based balloon-borne radiosondes for the first time. One of the reasons the models have been in such poor agreement on the long-term fate of Sandy is that the strength of this trough has not been very well known, since it has been over the ocean where we have limited data. Now that the trough is over land, it will be better sampled, and the next set of 12Z model runs, due out this afternoon between 2 pm – 4pm EDT, will hopefully begin to converge on a common solution. I’ll have an update this afternoon once the 12Z model runs are in.


Figure 4. Morning satellite image of Tropical Storm Tony.

Tropical Storm Tony forms in the middle Atlantic
Tropical Storm Tony formed Tuesday night in the middle Atlantic, becoming the nineteenth named storm of this very busy 2012 Atlantic hurricane season. Tony has a modest area of heavy thunderstorms, as seen on visible satellite images, but is battling dry air , wind shear, and ocean temperatures that have fallen below 26°C. Tony will not threaten any land areas, and will likely be dead by Thursday night.

Tony’s place in history
Tony is the Nineteenth named storm of the 2012 Atlantic hurricane season, tying this year with 1887, 1995, 2010, and 2011 for third busiest Atlantic season since the HURDAT historical data base began in 1851. With five more weeks left before the November 30 end of hurricane season, 2012 is likely to move into second place for most named storms before the year is out, as all six prior Atlantic hurricane seasons with nineteen or more named storms have had at least one named storm form after October 24. Here, then, is a list of the seven busiest Atlantic hurricane seasons on record:

2005 (28 named storms)
1933 (20 named storms, according to a new re-analysis)
2012 (19 named storms)
1887 (19 named storms)
2010 (19 named storms)
2011 (19 named storms)
1995 (19 named storms)

It’s pretty remarkable that we’ve now had three straight years with nineteen named storms in the Atlantic. But how many of these storms might not have been counted in the pre-satellite era (before 1960)? Here’s a list of weak and short-lived storms from 2010 – 2012 that stayed far out sea, and would likely have gone unnoticed in the pre-satellite era:

2012:
Tropical Storm Joyce
Tropical Storm Oscar
Tropical Storm Tony

2011:
Tropical Storm Jose
Tropical Storm Franklin

2010:
Tropical Storm Gaston

Even if we correct for the possible over-count of approximately two named storms per year during the 2010, 2011, and 2012 hurricane seasons, compared to the pre-satellite era, there is nothing in the HURDAT data base that compares to the type of activity we’ve seen the past three years. One likely contributor to the unusual string of active years is the fact hurricane season has gotten longer, perhaps due to warming ocean temperatures. I discussed in a 2008 blog post that Dr. Jim Kossin of the University of Wisconsin published a 2008 paper in Geophysical Research Letters titled, “Is the North Atlantic hurricane season getting longer?” He concluded that yes, there is a “apparent tendency toward more common early- and late-season storms that correlates with warming Sea Surface Temperature but the uncertainty in these relationships is high”.

Jeff Mastersfrom:    http://www.wunderground.com/blog/JeffMasters/article.html

Dr. Jeff Masters on North Atlantic Storms

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99L a heavy rainfall threat for Jamaica, Haiti, and Eastern Cuba
Published: 2:35 PM GMT on October 21, 2012

A tropical wave embedded in a large trough of low pressure (Invest 99L) covers a large portion of the Central Caribbean between Hispaniola and the northern coast of South America. This storm has the potential to be a dangerous rainfall threat for Haiti, Jamaica, and eastern Cuba. The disturbance is headed west at less than 5 mph, is over very warm waters of 29°C, and is in a moist environment. 99L has a large area of heavy thunderstorms that have a good degree of spin. These thunderstorms are beginning to organize into spiral bands, as seen on visible satellite loops. However, the amount of heavy thunderstorm activity is about the same as yesterday, and there are no signs of a surface circulation. An Air Force hurricane hunter aircraft is scheduled to investigate 99L this afternoon, but I expect this flight will be rescheduled for later.


Figure 1. Morning satellite image of Invest 99L.

Forecast for 99L
Wind shear is a low 5 – 10 knots, and is forecast to be in the low to moderate range, 5 – 20 knots, through Tuesday. This should allow for some steady development of 99L, and there has been a good deal of model support for 99L becoming a tropical depression by Wednesday. Steering currents favor a continued slow westward movement for 99L through Tuesday. On Wednesday, a strong trough of low pressure to the north of 99L is expected to turn the storm to the north or north-northeast, which should put 99L in the vicinity of Jamaica on Wednesday and Eastern Cuba on Thursday. By Friday, 99L should be in the Central or Eastern Bahamas. It is unclear at this point whether or not the trough pulling 99L to the north will be strong enough to pull the storm all the way out to sea to the northeast; a narrow ridge of high pressure has the potential to build in over 99L late this week and force the storm west-northwest, with a potential threat to the western Bahamas and U.S. East Coast by next weekend. In their 8 am EDT tropical weather outlook, NHC gave 99L a 70% chance of developing into a tropical cyclone by Tuesday morning. 99L will be capable of bringing heavy rains of 5 – 10 inches, with isolated amounts of up to 15 inches in mountainous areas, to Jamaica and Haiti, Monday through Wednesday. Heavy rains will begin on Tuesday in Eastern Cuba, and spread northwards into the Central and Eastern Bahamas by Wednesday.

Invest 90L in the middle Atlantic
A tropical wave (Invest 90L) about 830 miles east-northeast of the northernmost Lesser Antilles Islands is headed west-northwest at about 10 mph. The disturbance has a small amount of heavy thunderstorms, as seen on visible satellite images, and has gotten tangled up with an upper-level low pressure system. This upper-level low is providing 90L the spin it needs to become a tropical cyclone, but is also pumping cool, dry air into the disturbance, which will keep any development slow over the next few days. Wind shear is a moderate 10 – 20 knots, and is forecast to remain in the moderate range until Tuesday. This may allow for some slow development of 90L before it encounters high wind shear of 20 – 30 knots on Tuesday night through Thursday. None of the reliable computer models develop 90L into a tropical cyclone, and it’s unlikely that 90L will affect any land areas. In their 8 am EDT tropical weather outlook, NHC gave 90L a 30% chance of developing into a tropical cyclone by Tuesday morning.

The next name on the list of Atlantic tropical storms for 2012 is Sandy.

from:    http://www.wunderground.com/blog/JeffMasters/article.html

Jeff Masters on NE Weather, Leslie, Michael, & New Waves

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Severe weather in the Northeast U.S.; updates on 90L, 91L, Leslie and Michael
Published: 4:07 PM GMT on September 08, 2012

A significant severe weather outbreak is underway today across much of the Northeastern U.S., including metro New York City and Philadelphia. NOAA’s Storm Prediction Center has placed the region in their “Moderate Risk” area for severe weather. A fall-like low pressure system with a very powerful cold front will sweep through the region today, triggering widespread severe thunderstorms that may organize into a “derecho” event with damaging winds covering a large swath of the Northeast. A few tornadoes may accompany the event, and several tornado warnings have already been issued in New York, with a possible tornado touchdown in the Point Breeze section of the Rockaway peninsula in Queens. The same storm system killed four people on Friday in northeast Oklahoma; three of the deaths occurred when strong thunderstorms winds blew a mobile home into a ravine. Record heat was observed in advance of the storm’s cold front yesterday; Wichita Falls, TX hit a record high of 109, the hottest temperature ever recorded there so late in the season. When the cold front blew through at 7 pm CDT, the temperature dropped 15 degrees in 16 minutes, falling to 66 degrees by midnight. Wunderground meteorologist Shaun Tanner has more on the severe weather potential for the Northeast in his blog.


Figure 1. Severe weather potential for Saturday, September 8, 2012.

90L in the Gulf not a threat to develop
A partial remnant of Hurricane Isaac off the coast of the Florida Panhandle, Invest 90L, continues to be disrupted by wind shear, and no longer has time to develop before landfall occurs along the Florida Gulf Coast tonight or Sunday. Visible satellite loops show that 90L has a small area of poorly organized heavy thunderstorms, which will bring some areas of heavy rain to Florida today and Sunday.

Leslie still struggling with cool waters
Tropical Storm Leslie continues to feel the impact of the the cool waters it stirred up due to its long pause south of Bermuda, and remains a 65 mph tropical storm. The storm has no eyewall, as seen on satellite loops, but has cleared out a large cloud-free center. As Leslie continues to move north over warmer water, the storm should be able to build an eyewall and become at least a Category 1 hurricane. However, Leslie is expected to pass far enough to the east of Bermuda today and tonight that top winds of 45 mph will be observed on the island. Bermuda radar shows a large area of heavy rain from Leslie is very close to the island.


Figure 2. Morning radar image of Tropical Storm Leslie from the Bermuda radar.

Forecast for Leslie
The strong trough of low pressure pulling Leslie to the north will bring Leslie very close to Newfoundland, Canada by Tuesday night or Wednesday morning. At that time, Leslie should be weakening due to cooler waters and increased wind shear, and is likely to be a tropical storm. Heavy rain will be the main threat to Newfoundland. The latest 11 am EDT NHC wind probability forecast calls for a 24% chance that Leslie will be a Category 1 or stronger hurricane Wednesday morning at 8 am EDT, when the storm will be near Newfoundland. Even if the core of Leslie misses Newfoundland, the island will still likely experience tropical storm-force winds, since 39+ mph winds will probably extend outward from its center 180 miles to its west on Tuesday and Wednesday. Large swells from Leslie continue to pounding the entire Eastern Seaboard, and are creating beach erosion and dangerous rip currents.


Figure 3. Hurricane Michael as seen by NASA’s Aqua satellite at 11:50 am EDT Friday September 7, 2012. At the time, Michael was a Category 2 hurricane with 105 mph winds. Image credit: NASA.

Hurricane Michael weakens to Category 2
Hurricane Michael remains a Category 2 storm with 105 mph winds, out over the open mid-Atlantic Ocean. Satellite loops show that Michael is still an impressive storm with a well-developed eye. None of the models show that Michael will threaten any land areas during the coming five days, and Michael will likely die at sea over cold waters northeast of Newfoundland in 5 – 7 days.

91L off the coast of Africa
A tropical wave that emerged off the coast of Africa on Friday has been designated Invest 91L by NHC today. Most of the reliable computer models are predicting that 91L will develop into a tropical depression by Wednesday. None of the reliable computer models foresee that this storm will be a threat to the Lesser Antilles Islands, but it is still early to be assuming that 91L will recurve harmlessly out to sea.

Jeff Masters on Current ATlantic Tropical Activity

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Isaac pounding Louisiana, Mississippi, Alabama, and Florida
Published: 4:01 PM GMT on August 29, 2012
Hurricane Isaac continues to lumber slowly northwestwards at 6 mph, as it pounds Louisiana, Mississippi, Alabama, and Florida’s Panhandle with torrential rains, high winds, and a damaging storm surge. The eye was partially over water for most of the 15 hours after Isaac’s official landfall at 7:45 pm EDT Tuesday night, but New Orleans radar shows the eye of the storm is now fully ashore near Houma. The radar echoes show some weakening on the west side of the eyewall, where dry air has infiltrated the storm. Wind shear remains light, and upper level outflow over Isaac is as impressive as we’ve seen so far, with a strong outflow channel to the north, and a respectable one to the south, as well. Infrared and visible satellite loops show a very large, symmetric, and well organized storm, and Isaac is going to be able to stay near Category 1 hurricane strength all day today. This will allow Isaac to drop rainfall amounts of 15 – 20″ in some areas of Louisiana before the storm is over. A few rainfall totals from Isaac through 11 am EDT:

9.26″ New Orleans Lakefront Airport
5.59″ Belle Chasse, LA
5.21″ Mobile, AL
3.65″ Hattiesburg, MS
3.42″ Gulfport, MS
2.81″ Biloxi, MS


Figure 1. Morning radar reflectivity image from New Orleans.

A dangerous storm surge event underway
Isaac is bringing a large and dangerous storm surge to the coast from Central Louisiana to the Panhandle of Florida. Late this morning was high tide along much of the coast, and the highest water levels of Isaac are likely being experienced at many locations. At 11:30 am EDT, here were some of the storm surge values being recorded at NOAA tide gauges:

8.0′ Waveland, MS
8.2′ Shell Beach, LA
2.0′ Pensacola, FL
4.6′ Pascagoula, MS
3.4′ Mobile, AL

The peak 11.06′ storm surge at 1:30 am EDT this morning at Shell Beach, which is in Lake Borgne, 20 miles southeast of New Orleans, exceeded the 9.5′ surge recorded there during Category 2 Hurricane Gustav of 2008. In general, the storm surge heights from Isaac have been more characteristic of a strong Category 2 hurricane, rather than the weak Category 1 hurricane one might suppose Isaac is, based on its top sustained winds of 75 – 80 mph. The Saffir-Simpson Scale for ranking hurricanes is only a crude measure of their potential impacts.

A storm surge estimated at 12′ moved up the Mississippi in Plaquemines Parish near Port Sulphur, LA, near 8:30 pm EDT Tuesday, causing overtopping of the levees and flooding of homes in the mandatory evacuation areas behind the levees. These levees were not part of the $14.5 billion levee upgrade New Orleans got after Hurricane Katrina, and were not rated to Category 3 hurricane strength, like the levees protecting New Orleans are. The surge continued upriver, elevating the water levels 10′ in New Orleans (103 miles upstream from the mouth of the Mississippi), 8′ in Baton Rouge (228 miles upstream), and 1.4′ at Knox Landing, an amazing 314 miles upstream. The river was 7′ low due to the great 2012 U.S. drought, and I suspect the near-record low flow rate of the river allowed the storm surge to propagate so far upstream. The salt water from the storm surge will be slow to leave the river, due to the continued winds of Isaac keeping the surge going, plus the very low flow rates of the river. One benefit of the heavy rains of 10 – 20 inches expected to fall over Louisiana over the next two days will be to increase the flow rate of the Mississippi River, helping flush the salt water out of the river. The low flow rates of the Mississippi had allowed salt water to move upriver to just south of New Orleans over the past few weeks, threatening the drinking water supply of Plaquemines Parish.


Figure 2. Tide gauge data from Waveland, Mississippi. The green line shows the storm surge. The red line is the storm tide, the height of the water above Mean Sea Level (MSL.) The storm tide at Waveland currently (9′) is 2′ higher than that of Category 2 Hurricane Gustav of 2008. Image credit: NOAA Tides and Currents.

Tropical Storm Kirk in the Central Atlantic
Tropical Storm Kirk formed Tuesday night in the Central Atlantic. Kirk’s formation at 03 UTC on August 29 puts 2012 in 4th place for earliest formation date of the season’s 11th storm. Only 2005, 1995, and 1933 had an earlier formation date of the season’s 11th storm. Kirk should stay well out to sea and not trouble any land areas.


Figure 3. Morning satellite image of Tropical Storm Kirk.

Invest 98L in the Eastern Atlantic
A tropical wave (Invest 98L) is about 750 miles west-southwest of the Cape Verde Islands, and is moving west to west-northwest at about 15 mph. In their 8 am EDT Tropical Weather Outlook, NHC gave 98L a 50% chance of developing by Friday morning. Several of the models develop 98L into a tropical depression by this weekend, but none of the reliable models foresee that 98L will be a threat to the Lesser Antilles. The storm may be a threat to Bermuda next week, but it is too early to say if it may threaten the U.S.

Jeff Masters

from:    http://www.wunderground.com/blog/JeffMasters/article.html

Latest on TS/Hurricane Isaac

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Isaac approaching hurricane strength
Posted by: Angela Fritz, 9:14 PM GMT on August 27, 2012 +26

Isaac is walking the line of hurricane status this afternoon after a hurricane hunter mission investigated the storm and found winds of 80+ mph with the SFMR instrument, which looks down at the surface from the plane and estimates what wind speeds are. This instrument has a notoriously rough time in doing so when there’s heavy rain, and since the strongest winds were recorded coinciding with the strongest rain, you can imagine that this region of high wind speed could be suspect. The hurricane hunter mission is still in the storm, so I imagine they will issue a special update if needed. Currently the best estimate of wind speed within the storm is 70 mph. Isaac’s pressure has been dropping today as well and is now 981 mb. Isaac is moving northwest at 12 mph–no change since this morning. Satellite loops show that Isaac remains large, though asymmetric, with most of the strong thunderstorm activity on the west and southwest side. Isaac’s southeast side continues to struggle with dry air and wind shear, which could help to moderate Isaac’s intensity as it approaches the coast.

An oil platform in the northern Gulf of Mexico is reporting sustained winds from the north-northeast at 40 mph this afternoon. A buoy west of Tampa, Florida is recording sustained winds around 30 mph, and platforms south of Louisiana are recording winds from 35-40 mph. The widespread heavy rain of yesterday has lightened up in Florida, but a strong line of thunderstorms in one of Isaac’s outer bands is training northward along and offshore of the east coast of Florida, affecting everyone from Miami to Jacksonville.

This afternoon the AP reported that Isaac’s death toll in Haiti jumped to 19, which puts Isaac’s total death count at 21. It appears most of the deaths in Haiti were due to collapsing structures.


Figure 1. Satellite imagery of Tropical Storm Isaac around 3pm EDT on Monday.

Track forecast:
Models seem to be coming into better agreement today on where Isaac will make landfall, closing in on Louisiana and New Orleans as most likely landfall point. The ECMWF, HWRF, and UKMET all suggest New Orleans as the landfall location. The GFS is only slightly west of that. The GFDL is the farthest west, predicting landfall near the Louisiana-Texas border. Landfall timing remains Tuesday night. Beyond landfall, Isaac is expected to move north toward the Midwest through the rest of this week, however, models are showing that the system will likely slow down around landfall time, prolonging impacts like surge and inland flooding.

Intensity forecast:
The closer Isaac gets to landfall without having formed an eye, the better it is for intensity at landfall. Isaac has strengthened only modestly in the past 24 hours, and is still struggling with a less-than-conducive atmospheric environment. The HWRF remains on the high end of the intensity spectrum, suggesting Isaac will be a weak category 2 upon landfall. Other models suggest it will be a strong category 1, but the difference is splitting hairs. The National Hurricane Center’s official forecast is for Isaac to continue strengthening over the next day, reaching category 2 at landfall.


Figure 2. Tide gauge data from St. Petersburg, Florida. The green line shows the storm surge. As Isaac’s counterclockwise winds blew offshore this morning, water levels feel two feet at St. Petersburg. The winds switched to onshore this afternoon as the center of Isaac moved more to the northwest, bringing a storm surge of two feet to the city.

Storm surge observations from Isaac
This morning, as Isaac’s counter-clockwise winds brought offshore winds to the Tampa/St. Petersburg area, ocean waters fell two feet along the coast. This afternoon, winds have shifted to blow onshore, and a two foot storm surge has been observed at Naples, Fort Meyers, and St. Petersburg on the west coast of Florida. Water levels have also begun to rise along the coast of Louisiana, with a storm surge of 1.5 feet already occurring at Shell Beach on the east side of New Orleans in Lake Borgne.

from:    http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2209

Jeff Masters On Hurricanes and Hispaniola

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Throughout hurricane history, numerous tropical storms and hurricanes have battered themselves against Hispaniola and Cuba. Some have been destroyed; others have survived and gone on to wreak additional havoc. Cuba’s most formidable barrier to hurricanes is the one Isaac will be running into–the eastern portion of the island, where mountains up to 6,000 feet high rear up out of the sea. I present here a history of five storms that crossed portions of both Hispaniola and Cuba, similar to Isaac’s track. These five storms strengthened by 5 – 20 mph in their first 24 hours after coming off the coast of Cuba, and one went on to become the deadliest disaster in American history–the Great Galveston Hurricane.

Tropical Storm Fay of 2008. This storm was so unpredictable, I nicknamed it “The Joker.” Fay got disrupted by passage over Haiti and Eastern Cuba, then slowly intensified to a 50 mph tropical storm as it tracked just south of Cuba. After crossing Central Cuba, Fay intensified from 50 mph to 65 mph in 36 hours over the Florida Straits, before making landfall in southwest Florida. Fay actually strengthened another 5 mph to a 70 mph tropical storm while its center was over land near the western end of Lake Okeechobee.


Figure 1. Tropical Storm Fay approaching Florida. Satellite: Aqua at 6:50 PM GMT on August 18, 2008

Hurricane Ernesto of 2006. Ernesto was a hurricane for the briefest of time, just six hours, before it encountered the rugged mountains on the southwest Peninsula of Haiti and Eastern Cuba, which weakened it to a 40 mph tropical storm. After popping off the north coast of Cuba, Ernest had 24 hours over the warm waters of the Florida Straits before making landfall on the southern tip of Florida, but Ernesto was only able to strengthen by 5 mph to 45 mph.


Figure 2. Hurricane Ernesto (05L) over Hispaniola. Satellite: Terra at 3:50 PM GMT on August 27, 2006

Hurricane Georges of 1998. This nasty Cape Verde hurricane cut a swath of destruction across the Caribbean and in the U.S., killing 602 people, mostly in Haiti and the Dominican Republic. Passage over Hispaniola weakened Georges from a Category 3 storm to a Category 1, and Georges was able to maintain Category 1 status for over a day while traversing the eastern half of Cuba. After the center popped off the coast, Georges had 18 hours over water before it hit Key West, and the hurricane intensified from 85 mph winds to 105 mph winds during that time.


Figure 3. Inside the eye of Hurricane Georges, as seen from a NOAA WP-3D research aircraft on 19 September 1998.

Hurricane Two of 1928. This storm became a Category 1 hurricane with 90 mph winds before reaching Haiti, the got disrupted by close passage to Haiti’s southwest peninsula, and Eastern Cuba. After the storm crossed Cuba, it strengthened from 60 mph to 70 mph in the Florida Straits, before close passage by the landmass of South Florida weakened it back to a 60 mph tropical storm again. It eventually made landfall in the panhandle of Florida as a 45 mph tropical storm.

Great Galveston Hurricane of 1900. This deadliest hurricane in American history killed an estimated 8,000 – 12,000 people in Galveston, Texas when it hit as a Category 4 storm with 145 mph winds on September 8, 1900. On its way to Galveston, the storm crossed both Hispaniola and the greater part of the length of Cuba as a tropical storm with 40 – 50 mph winds. When the storm popped out into the Florida Straits, it intensified from a minimum strength 40 mph tropical storm to a 145 mph Category 4 monster in two-and-a-half days. There’s a very good chance the hurricane passed over a warm core Gulf eddy on its way to Galveston, allowing explosive deepening to occur. That situation does not exist in the Gulf at present for Isaac.


Figure 4. Aftermath of the Great Galveston Hurricane of 1900 on Galveston Island.

from:    http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2203

Jeff Masters On Current Tropical Storms

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94L a threat to the Lesser Antilles; Gordon a hurricane; Helene hits Mexico
Posted by: Dr. Jeff Masters, 3:24 PM GMT on August 18, 2012 +22

A large tropical wave that emerged from the coast of Africa Thursday night (Invest 94L) is located a few hundred miles southwest of the Cape Verde Islands off the coast of Africa, and is headed west at 15 – 20 mph. This storm is a threat to develop into a tropical storm that will affect the Lesser Antilles Islands as early as Wednesday. The storm is under moderate wind shear of 10 – 20 knots, and is over waters of 27.5°C. A large area of dry air lies just to the north of 94L, as seen on the latest Saharan Air Layer (SAL) analysis. This morning’s 8:15 am EDT ASCAT pass caught the east side of 94L, and showed a partial surface circulation. Satellite images show just a modest amount of heavy thunderstorm activity, and I expect the earliest that 94L could develop into a tropical depression would be Sunday.


Figure 1. Morning satellite image of Invest 94L.

Forecast for 94L
The latest 8 am EDT run of the SHIPS model predicts that wind shear will be low, 5 – 10 knots, and ocean temperatures will gradually warm from 27.5°C to 28.5°C over the next four days, as 94L tracks westwards towards the Lesser Antilles. As is typical with storms making the crossing from Africa to the Antilles, dry air to the north will likely interfere with development. However, with shear expected to be low, dry air may be less of an issue for 94L than it was for Ernesto or TD 7. The storm should maintain a nearly due west track through Monday night, to a point near 50°W, about 700 miles east of the Lesser Antilles. At that point, a trough of low pressure passing to the north of 94L may be able to pull the storm more to the northwest, as suggested by the latest 06Z (2 am EDT) run of the NOGAPS model, and by three members of the GFS model ensemble forecast (Figure 2.) However, the models have been trending more towards a solution where this trough is not strong enough to influence 94L’s path. This scenario will be more likely if 94L takes its time to develop, since a weaker storm will be smaller and shallower, and less likely to respond to the trough passing to the north. Our two best performing models, the GFS and ECMFW, both take 94L through the Lesser Antilles. The ECMWF, which predicts that 94L will stay weak and not develop, is faster, bringing the storm through the Lesser Antilles on Wednesday. The GFS model is slower, bringing 94L to the Lesser Antilles on Thursday as a hurricane. The models have shown poor run-to-run consistency in both the timing and the track of 94L, so it is difficult to assess which land areas might be most at risk, and when. A database of historical probabilities of storms in the same location as 94L maintained by Dr. Bob Hart of Florida State University reveals that historically, 45% of storms in this location have eventually hit land, with Canada (13% chance) and North Carolina (15% chance) the most likely targets. In their 8 am EDT Tropical Weather Outlook, NHC gave 94L a 40% chance of developing into a tropical depression by Monday morning.


Figure 2. The 00Z (8 pm EDT) run of the GFS model from August 17, 2012, was done 20 different times at low resolution using slightly different initial conditions to generate an ensemble of forecasts (pink lines.) The high-resolution operational GFS forecast is shown in white.

Gordon becomes a hurricane
Hurricane warnings are flying for the central and eastern Azores Islands as Hurricane Gordon heads eastwards at 18 mph. Gordon became the third hurricane of the 2012 Atlantic hurricane season at 5 am Saturday morning, and is sporting an impressive-looking eye on visible satellite loops. Gordon should be able to maintain hurricane status until Sunday, when wind shear will rise steeply to 30 – 40 knots, and ocean temperatures will drop to 25°C. The combined effects of high wind shear, dry air, and cooler waters will likely act to weaken Gordon to a strong tropical storm by the time it arrives in the Azores Islands Sunday night, but the storm will be strong enough to bring damaging winds and heavy rain to the Azores Islands. Gordon is not a threat to any other land areas, and the extratropical remnants of Gordon will not bring any strong winds or significant rain to Europe. The last time the Azores were affected by a tropical storm was in 2009, when Tropical Storm Grace brought 65 mph winds on October 4. No significant damage was reported. Ironically, the last hurricane to affect the Azores was the 2006 version of Hurricane Gordon, which caused minor damage in the Azores, consisting of mostly fallen trees and power outages. However, after Gordon became an extratropical low, four injuries due to falling debris from high wind were reported in Spain, and Gordon brought high winds and rain that affected practice rounds at the Ryder Cup golf tournament in Ireland. About 126,000 homes were without power after the storm in Northern Ireland and one injury was reported.


Figure 3. Morning satellite image of Hurricane Gordon.

Helene makes landfall in Mexico
Tropical Storm Helene made landfall near 10 am EDT as a tropical storm near Tampico, Mexico, with 40 mph winds. Helene’s formation on August 17 ties 2012 with 1933 for the 2nd earliest appearance of the Atlantic’s eighth tropical storm. Helene’s rains should remain south of Texas, but moisture from Helene may feed into a stalled frontal system over the northern Gulf of Mexico and bring heavy rains to the northern Gulf Coast early next week.

from:    http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2191