Talking the Tropics With Mike: Leslie goes hurricane over Atlantic 1,000+ miles from Jacksonville

Thunderstorms continue over the Caribbean

Oct. 3, 2018 — The "Buresh Bottom Line": Always be prepared!.....First Alert Hurricane Survival Guide... City of Jacksonville Preparedness Guide... Georgia Hurricane Guide.  

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Leslie has turned hurricane while spending the week moving very slowly over the Central Atlantic making a gradual curl before heading north then northeast & even east by the weekend.  The storm's swell will affect the Florida coastline & much of the U.S. east coast through much of the week & - when combined with onshore flow - result in a high rip current risk at area beaches.  Otherwise Leslie will stay far away from any land areas.

A cluster of strong convection persists over the Caribbean.  Broad low pressure has developed but t'storm activity lacks much organization & there is a fair amount of mid & upper level shear at the moment. Tropical development over the Caribbean &/or SW Atlantic appears probable next week but the end result is still - as one would expect at this early juncture - far from certain.

Atlantic Basin:

The overall pattern through the first two weeks of Oct. will favor tropical development over the Atlantic Basin.  The velocity potential anomaly map below indicates expansive green lines - upward motion - spreading from the E. Pacific into the Atlantic Basin, part of a MJO (Madden-Julian Oscillation) pulse.  While tropical development could occur just about anywhere, it would appear we especially need to be vigilant of the Caribbean &/or Southwest Atlantic from approximately Oct. 6 through the 16th.

The area of concern matches up with the "hot spots" for Oct. tropical cyclone genesis (development):

CIMMS satellite below shows the extent of dry air but also indicates it doesn't necessarily shut down the basin.  Note the considerable dry air between Leslie & Florida which will help to shut down widespread rainfall for Jacksonville/NE Fl./SE Ga. through Friday/Saturday.

E. Atlantic:

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Mid & upper level wind shear (enemy of tropical cyclones) analysis (CIMMS). The red lines indicate strong shear:

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The Atlantic Basin....

Caribbean:

Gulf of Mexico:

Water vapor imagery (dark blue indicates dry air) - notice the dry air spinning into Leslie:

Deep oceanic heat content is seasonably high over the Caribbean, Gulf of Mexico & SW Atlantic as one would expect early in the fall....

Sea surface temp. anomalies:

SE U.S. surface map:

Surface analysis centered on the tropical Atlantic:

Surface analysis of the Gulf:

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Caribbean:

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The E. Pacific remains active....

"Sergio" is strengthening well offshore of Mexico, far to the south of the Baja & will turn northwest over open water through late week then veer back to the west.

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