Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.
By: Dr. Jeff Masters , 2:54 PM GMT on November 15, 2010
An area of disturbed weather (Invest 94L) in the southern Caribbean between Colombia and Nicaragua has seen a modest increase in thunderstorm activity this morning, but is battling dry air, and the odds are against the system becoming Tropical Storm Virginie. Satellite images show that 94L has a limited amount of heavy thunderstorms, but the activity is increasing, and a low-level circulation is getting better defined. Water vapor satellite images show a large amount of dry air lies to the north over the northern Caribbean, and this dry air is slowing development. SSTs are warm, 29°C, and wind shear as analyzed by the University of Wisconsin CIMSS group is a moderate 10 - 15 knots.
Figure 1. Morning satellite image of 94L.
Forecast for 94L
The latest SHIPS model forecast predicts that wind shear will remain in the moderate range, 10 - 20 knots, for the next five days. The modest shear and warm SSTs may allow for some slow organization of 94L over the next few days, if the storm can wall off the dry air at mid-levels that has been interfering with development. The models predict that the steering currents in the southern Caribbean will keep 94L moving generally west-northwestward at about 5 - 10 mph for the next three days, which would bring the storm ashore over Nicaragua or northeast Honduras on Wednesday. The models are not showing much development of 94L, and NHC is giving the system just a 20% chance of developing into a tropical depression by Wednesday. I'd put the odds higher, at 30%. The Hurricane Hunter mission into 94L scheduled for today has been canceled, but is slated to go on Tuesday afternoon. At this time, it appears that 94L will stay confined to the Caribbean, and will not be drawn northwards across Cuba towards Florida and the Bahamas.
I'll have an update Tuesday.
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