T.S. Ernesto continues to move in a generally westward direction this weekend. The storm looks very impressive in satellite imagery, but has gone through cycles of strengthening and weakening due to dry air and moderate wind shear.
T.S. Ernesto’s position is ~14.5N, 69.3W; minimum central pressure 1004mb; maximum sustained winds 50mph; moving W @ 18mph (rather quick for a tropical system).
The NHC is forecasting Ernesto to become a hurricane in the western Caribbean as the storm moves over water with higher heat content. There is large uncertainty in this forecast because of the wide spread of model solutions of storm intensity. The intensity the storm does possess will make a large contribution in the determination of its path. If the storm stays weak, it should hit Belize or the Yucatan Peninsula early on Wednesday (the GFS, BAMM and UKMET models show this solution). If the storm strengthens to a Category 1 or 2 hurricane, it should follow a weakness in the ridge guiding its movement due to a frontal system moving east across the US early in the week. If this happens, the storm could take a path east of the Yucatan Peninsula and move in the Gulf of Mexico (as shown by the GFDL and HWRF models) where it would likely continue to intensify prior to a US landfall. As of right now, the NHC’s official track forecast takes Ernesto over the Yucatan, north of Belize, then into the southwestern Gulf of Mexico on Thursday.
It is worth mentioning that the US is currently in the midst of the longest streak without a major hurricane making landfall on the continental US (2,476 consecutive days and counting). The last storm to do so was Hurricane Wilma on December 4, 2005!
T.S. Florence strengthened from a very vigorous African tropical wave late yesterday. She formed WSW of the Cape Verde islands and is moving generally westward across the Atlantic.
T.S. Florence’s center is currently at 14.8N 30.6W; her minimum central pressure is ~1002mb; maximum sustained winds are at 45mph; moving WNW @ 16mph.
Storms like Florence usually remain well out in the middle of the ocean and don’t impact landmasses such as the US or even the Caribbean. Their exact paths are taken in response to the strength and position of the ridge of high pressure over the Atlantic as well as the transit of mid-latitude troughs north of the tropics that temporarily weaken that ridge.
T.S. Florence is officially projected to continue moving approximately WNW to NW over the next five days. By Thursday, the storm could be well northeast of the Lesser Antilles. The extended range GFS model keeps Florence out to sea with the storm turning to the north hundreds of miles east of the US coast. Florence could experience some trouble strengthening due to the lower sea surface temperatures and lack of deep warm water from which to grow.
Note that yesterday was the 3rd earliest date on which the 6th storm of the Atlantic season formed.