Tropical Storm Ernesto lashed the Windward Islands with strong winds and heavy rain early this morning, as it passed over St. Lucia near 7 am AST. Ernesto brought sustained winds of 43 mph to Barbados at 7 am AST, and sustained winds of 41 mph, gusting to 63 mph to St. Lucia at 6:15 am AST. Ernesto looks moderately well-organized on Martinique radar, with spiral bands to the north and south feeding into an echo-free center. Ernesto is beginning to show more organization on visible satellite loops, with the very limited heavy thunderstorm activity near its center now expanding, spiral banding increasing, and an upper-level outflow channel developing to the north. Ernesto is fighting moderate wind shear of 10 – 20 knots, and water vapor satellite loops show a large area of dry air to the west. Strong upper level winds from the west are driving this dry air into the core of the storm, disrupting it. It appears, though, that Ernesto has fended off the most serious challenges to its survival, as the pressure has fallen to 1002 mb, and the storm’s appearance on radar and satellite is gradually improving. The latest 7:30 am center report from the Hurricane Hunters also indicated that Ernesto was beginning to build an eyewall.

Figure 1. Radar image of Ernesto at 9:15 am EDT August 3, 2012. Image credit: Meteo France.

Figure 2. Morning satellite image of Ernesto.

Forecast for Ernesto
Ernesto’s survival into today means that the storm now potentially poses a formidable threat to the Western Caribbean. Wind shear is expected to drop to the low range, 5 – 10 knots, later today, and remain low for the next five days, according to the 8 am EDT run of the SHIPS model. With the storm entering a moister environment with increasing heat energy in the ocean, the official NHC forecast of Ernesto reaching hurricane strength by early Monday morning near Jamaica is a reasonable one. The reliable computer models predict a west to west-northwest motion through the Caribbean, with the storm’s heavy rains staying south of Puerto Rico and the Dominican Republic. The more southerly path predicted by the usually reliable ECMWF model, which brings Ernesto to a landfall in Belize on Wednesday, is being weighted less heavily by NHC, since they are assuming Ernesto will stay stronger than the ECMWF model is forecasting. Once Ernesto enters the Central Caribbean on Sunday, the storm’s outer spiral bands will likely cause flooding problems in Southwest Haiti, Jamaica, and the Cayman Islands. Of the major dynamical models NHC uses operationally–the ECMWF, GFS, NOGAPS, UKMET, GFDL, and HWRF–none clearly show Ernesto reaching hurricane strength in the Caribbean. However, some of the best statistical models, such as the LGEM and SHIPS, do show Ernesto becoming a hurricane in the Caribbean. By Monday, a trough of low pressure passing to the storm’s north may be capable of turning Ernesto more to the northwest, resulting in the storm entering the Gulf of Mexico by the middle of next week.

New African tropical disturbance 90L
A strong tropical wave is located just off the coast of Africa, about 175 miles south of the Cape Verde Islands. This disturbance, designated Invest 90L by NHC Friday morning, is headed west-northwest at 10 – 15 mph. Wind shear is a high 20 – 30 knots over 90L, but is expected to drop, and water temperatures are warm enough to support development. NHC gave 90L a 30% chance of developing into a tropical depression by Sunday morning in their 8 am Friday Tropical Weather Outlook.

Kuwait hits 53.6°C (128.5°F): 2nd hottest temperature in Asian history
An extraordinary high temperature of 53.6°C (128.5°F) was recorded in Sulaibya, Kuwait on July 31, the hottest temperature in Kuwait’s history, and the 2nd hottest temperature ever measured in Asia. According to weather records researcher Maximiliano Herrera, Sulaibya is in a location well-suited for recording extreme high temperatures, since high sand dunes surround the site, keeping the wind low and hampering sea breezes from cooling the city. Most record books list the 54°C (129.2°F) recorded on 21 June 1942 in Tirat Zvi Israel as the site of Asia’s all-time maximum temperature, but this record is disputed. The previous second warmest temperature in Asian history was set 53.5°C (128.3°F) at MohenjuDaro, Pakistan on May 26, 2010.

Extreme heat in Oklahoma
The most intense and widespread heat wave in Oklahoma since August, 1936 brought more than half of the state temperatures of 110° or higher for the second consecutive day on Thursday. The temperature at the Oklahoma City airport hit 112°, for the 2nd day in a row. These are the city’s 2nd highest temperatures since record keeping began in 1890. The only hotter day was August 11, 1936, when the temperature hit 113°. Thursday’s temperatures in Oklahoma were generally a degree or two cooler than Wednesday’s, with the hottest temperature reported a 116° reading from a location just south of Tulsa International Airport. The highest reading Thursday at any major airport was a 114° temperature at Tulsa Jones Airport. Oklahoma’s all-time state record is 120°, set in Tipton on June 27, 1994, and at three locations in 1936. Freedom, in the northwest part of the state, hit 121° on Wednesday, but this reading will need to be reviewed to see if the sensor was properly sited.

Jeff Masters

from:http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2170