FORECAST POSTED: 8/28/02/ 10:00 PM EDT
Tropical Weather Outlook
We expect the 1010MB low centered near 9N27W to be upgraded to a tropical depression with 35MPH winds later tonight. Elsewhere, tropical storm formation isn not expected over the next 48 hours.
Tropical Weather Discussion
The low south of the Cape Verde Islands has continued to show signs of organization thoughout the day, with the strongest convection circulating around the low level center. The afternoon visible satellite also showed impressive inflow associated with this system. However, the National Hurricane Center may not upgrade the low/depression until the QUICKSCAT can provide them with enough evidence that there is a closed center. The low will be upgraded to a TD before noon tomorrow...thats almost a garauntee.
The models are still having a hard time with this low. The majority of the models still aren't forecasting development. In addition, they have been in agreemwnt that the low will pass north of the islands. However, each run has indicated a more westward track.
The low/TD/TS will be under favorable upper level winds for at least 72 hours. This should give the low plenty of time to become our fourth named storm of the 2002 season. Chances of this low becoming Dolly are about 9/10. I suggest that the Lesser Antilles closely monitor this system... There is a 50/50 chance of Dolly hitting the islands, if it survives the shear farther west. Dolly is six days away from the islands.
Dolly will develop...no doubt about that. The question is, will Dolly survive the trip across the Atlantic Basin. Currently, the Tropical Upper Tropospheric Trough (TUTT) has been enhanced by a large upper level low near 30N. If the shear doesn't weaken by the time Dolly moves into the area, she will be sheared apart just like Debby in 2000. However, we must remember that if this storm develops at a moderate rate over the next few days, it could make its own environment and SLIGHTLY decrease the vertical shear. Now if this was already a stronger system, shear wouldn't be much of a problem at all. In addition, an upper level ridge will develop in the area, which could also weaken the shear somewhat. So there is the potential that Dolly could survive the TUTT. If this does happen, the southeast could be in trouble down the road. the ridge will be centered over the Bahamas, which means favorable conditions over the area. But the TUTT is the key factor. It is too early to speculate on whether or not Dolly will survive.
We are still watching the broad low over the southwest Caribbean Sea. However, there are no signs of a low level center. In addition, there is still a lot of persistent shear over the area. Therefore, development isn't expected.
The wave southeast of the Bahamas still isn't showing much in the way of development. There has been a lot of isoldated convection over the southwest atlantic over the past few days...however, there are no signs of organization. Conditions are favorable for development but as long as I don't see organization I don't see much in the way of development.
Another tropical wave will emerge off of the coast of Africa over the next few days. The models dont suggest development...but they're not forecasting development from the low south of the Cape Verdes neither. This is another wave that we will have to monitor in the east Atlantic.
This is probably the beginning of the burst of tropical activity I have been forecasting. The NAO is still negative and the strongest of the negative MJO is still to come.
FORECASTER: Jason Moreland, TWWFT
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