Vigorous tropical wave coming off Africa this weekend – will need watching closely
From Dr Jeff Masters Weather Underground
Little change to 97L headed towards the Lesser Antilles
A tropical wave (Invest 97L) was near 13°N, 47°W on Tuesday morning, about 900 miles east of the Lesser Antilles Islands, and was headed west to west-northwest at about 15 mph. Satellite loops show the wave has changed little since Monday, and has a modest amount of spin but only a small amount of heavy thunderstorms. Water vapor satellite images and the Saharan Air Layer analysis show that 97L is located in a dry environment, which is keeping development slow. Wind shear was a moderate 10 – 20 knots, which should allow some slow development. Sea Surface Temperatures are near 27.5°C, which is warm enough to allow some slow development. The wave should arrive in the Lesser Antilles Islands by Friday and be near Puerto Rico on Saturday, according to the Tuesday morning runs of the GFS model. None of the three reliable computer models for predicting tropical storm formation predict 97L will develop over the next five days. In their 8 am EDT Tuesday Tropical Weather Outlook, NHC gave 97L 2-day and 5-day development odds of 0% and 20%, respectively. These odds are 10% lower than their previous advisory, and NHC has stopped running their suite of models on 97L.
New tropical wave coming off coast of Africa this weekend
A large and powerful tropical wave will move off the coast of Africa on Friday evening, and the GFS model has been very aggressive in recent runs about developing this wave into a tropical storm within a day of its emergence. The other reliable models for tropical cyclone genesis, the European and UKMET models, have not been developing this wave right away. Residents of the Cape Verde Islands should anticipate the possibility of heavy rain and strong winds on Saturday as the wave moves west at 10 – 15 mph across the islands. In their 8 am EDT Tuesday Tropical Weather Outlook, NHC gave 97L 2-day and 5-day development odds of 0% and 30%, respectively.
The Gulf of Mexico is worth watching
In the Gulf of Mexico, heavy thunderstorm activity has diminished since Monday along a weak cold front stretching from South Florida to the Louisiana coastal waters. Some models show a weak area of low pressure developing along this front and moving westwards over Texas by Friday, and we should keep an eye on this region for development.
Hurricane CRISTOBAL Northbound – ‘97L’ Needs Monitoring – Strong System over Africa
By Steve Gregory From Weather Underground
HURRICANE CRISTOBAL
CRISTOBAL intensified into a hurricane early last night as wind shear eased a bit, and outflow improved somewhat to the North and south. Shear remains relatively high near 20Kts, and with no improvement in the outflow pattern above the storm expected and the proximity to drier to its west – significant intensification appears unlikely as the 988mb storm moves Northward during the next 2 days along the western periphery of the sub-tropical (Bermuda) High centered in the central Atlantic. All the models are now in excellent agreement on both the track and intensity forecast for CRISTOBAL, and except for large waves and localized rip currents along the east coast – CRISTOBAL will have no impact on the US mainland
INVEST 97L POSES A POTENTIAL THREAT OF DEVELOPMENT THIS WEEKEND
Although NHC dropped 97L overnight, this system is now BACK on the NHC home page chart, most likely due to several global models now forecasting it to develop this weekend as it approaches the Leeward Islands – with the GFS and a few other models tracking it as a cyclone into the southeast coast of the US mainland late next week. Because NHC ‘dropped’ the system over night, none of the specialized hurricane models we executed during the 12Z cycle run. However, the models will almost certainly be initialized for the 18Z cycle run later today. That said – the system is currently surrounded by dry and somewhat stable air with no significant outflow signature seen on SAT imagery at this time; so development, if any, will be quite slow for the next 72 hours.
STRONG DISTURBANCE STILL WESTBOUND OVER AFRICA
Finally, the strongest African tropical disturbance of the season is now located over west-central Africa with a long history of deep convection and a well established rotation in low to mid levels. The disturbance is now moving slowly westward, and is expected to emerge off the west African coast this weekend. Some model projections forecast this system to gradually intensify next week – but also put it on a more Northwesterly track next week – implying this system will start heading out to sea by later next week.
For more on both the above stories go to: http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2776
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Hurricane Cristobal drenches Caribbean Islands, leaves 5 dead before heading toward Bermuda
By Philip Ross From International Business Times
Tropical Storm Cristobal is pictured near Turks and Caicos Islands August 24, 2014. Cristobal has become the third hurricane of the 2014 Atlantic season, the U.S. National Hurricane Center said Monday. NASA
Hurricane Cristobal continued its march north across the Caribbean on Tuesday morning after dumping heavy rains on parts of Puerto Rico, the Bahamas, the Dominican Republic and Haiti. The hurricane, which formed over the Atlantic Ocean over the weekend and gained strength Monday, flooded several Caribbean communities, halted flights in the Turks and Caicos Islands, and left at least five people dead before heading north toward Bermuda, the Associated Press reported.
In Haiti, at least two dozen homes were heavily damaged and several others were destroyed. Hundreds of Haitian families were left temporarily homeless from the storm, the Associated Press reported. Authorities evacuated some 3,600 people from coastal communities in the Dominican Republic. Two men in the Dominican Republic and two in Haiti were killed after being swept away by swollen waterways; a fifth fatality was reported in Turks and Caicos.
Meteorologists upgraded Cristobal to a Category 1 hurricane Monday night, making it the third hurricane of the Atlantic hurricane season. Maximum sustained winds reached 75 mph, according to the National Weather Service.
The hurricane will reach Bermuda Wednesday (27) before banking northeast, meteorologists report. Although Cristobal is expected to bypass the U.S. East Coast, scientists warn of high surf and coastal flooding in northeast Florida, the Outer Banks of North Carolina and southeast Virginia. Rip currents are also possible along the Eastern Seaboard through Wednesday, according to the Weather Channel.
For more on this story go to: http://www.ibtimes.com/hurricane-cristobal-drenches-caribbean-islands-leaves-5-dead-heading-toward-bermuda-1669682
Caribbean begins recovery efforts after Tropical Storm Cristobal
From Caribbean Journal
The northern Caribbean region is beginning recovery efforts in the wake of Tropical Storm Cristobal.
The storm caused damage in several parts of the region, including the Turks and Caicos, Haiti and the Dominican Republic, and the deaths of at least five people across the Caribbean.
The Turks and Caicos Islands has begun recovery efforts following significant damage from flooding, after 12 inches of rain fell on the British Overseas Territory from Aug. 23 to Aug. 24, with flood water several feet deep in some places.
The TCI Government Executive Policy Committee met Monday to discuss the recovery plan, looking to determine how much damage was caused by the storm and to determine the allocation of resources to assist in recovery efforts.
“The images that I have seen, and the brief received from our colleagues who flew over the islands in a US Coast Guard aircraft today, have left us in no doubt of the extensive damage to people’s property and possessions,” Governor Peter Beckingham said.
Flights have resumed at Providenciales International Airport as of 8:30 AM Tuesday morning, however.
All domestic and international carriers have resumed service to the Turks and Caicos Islands, following a two-day interruption of service due to the storm.
“Our immediate action items remain further assessing the extent of the damage inflicted by Tropical Storm Cristobal especially in the islands of Middle & North Caicos,” said TCI Premier Dr Rufus Ewing. “We are sending specialist staff to help those in greatest need, and to better assess the situation.”
In the Dominican Republic, almost 4,000 people were evacuated due to the storm.
In Haiti, which has been hit particularly hard by several storms in the region in recent years, at least two people were killed and dozens more injured due to flooding and road accidents.
There is no clear estimate of the cost of the damage so far.
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