Talking the Tropics With Mike: Kirk falling apart upon moving into the Caribbean

Sept. 28, 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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Kirk brought tropical storm conditions to the parts of the Lesser Antilles through early Fri.  The tropical cyclone is encountering high shear which continues to seriously interrupt the storm's organization.  As Kirk weakens & moves to the west, conditions will rather quickly improve across the Lesser Antilles. The 30+ mph shear should tear the low level center from the mid & upper level air centers turning Kirk more west with the shallow trade winds.  No regeneration is expected once decoupling of the mid & low level center occurs.

Leslie remains over the N. Atlantic & should regain tropical or subtropical characteristics over the weekend into next week but remain over open water.  The huge storm's swell will affect the Florida coastline through much of next week & - when combined with onshore flow - result in a high rip current risk at area beaches.

Soon to be subtropical Leslie over the N. Atlantic.... Kirk in the Caribbean:

CIMMS satellite below shows the extent of dry air but also indicates it doesn't necessarily shut down the basin. Arguably shear is a bigger inhibitor right now, especially for Kirk.  Check out! the swirl of the huge ocean storm over the N. Atlantic which will likely become Leslie again .... despite the abundance of dry air while another strong wave is over the far E. Atlantic.

E. Atlantic with another impressive wave moving off Africa:


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


The Atlantic Basin....


Gulf of Mexico:

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

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 Western Caribbean &/or Gulf of Mexico from approximately Oct. 5 through the 15th.

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:




Over the E. Pacific.... powerful hurricane "Rosa" is strengthening while moving west.  This will be an interesting tropical cyclone early next week as Rosa turns sharply north through the weekend then makes a move for the Northern Baja of California by Monday.  Though weakening, it's possible that Rosa will still be a tropical storm upon landfall Tue. not all that far south of California & Arizona.  In any case.... heavy rain may spread north into the Southwest U.S. early next week.