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Kirk's will bring tropical storm conditions to parts of the Lesser Antilles through Thu. evening. This fast moving storm is encountering high shear near & over the Caribbean which has seriously interrupted the storm's organization. The shear should protect the Lesser Antilles from a major storm but there will still be very heavy rain & gusty winds along with rough seas/surf - especially for the northern islands - into Thu. night but conditions will quickly improve Fri. Once into the Caribbean, shear at a 30+ mph magnitude 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.
Shear analysis of the Caribbean shows 30-40+ mph mid & upper level winds in front of Kirk!:
Leslie remains over the N. Atlantic & should regain tropical or subtropical characteristics over the weekend into nexst week but remain over open water.
Soon to be subtropical Leslie over the N. Atlantic.... Kirk entering 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.
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 now that we're near the height of the hurricane season....
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.... hurricane "Rosa" is strengthening while moving west. This will be an interesting tropical cyclone next week as Rosa turns sharply north over the weekend then makes a move for the Northern Baja of California by the middle of next week. 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. by the middle of next week.
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