Talking the Tropics With Mike: Weak tropical wave approaching the Caribbean

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After 1 named storm in July - "Barry" (marginal hurricane at most), we head into the busier part of the Atlantic hurricane season.  The third named storm is usually "on the map" by Aug. 13... the 4th by Aug. 23 & the 5th by Aug. 31 (43 years of data).  In other words, we're about right on schedule so far.

The weak tropical wave that dropped heavy rain on Jacksonville & much of Central & South Florida late last week but did not develop - as expected/forecast - has merged with a frontal system strung out across the Atlantic.  The disturbance will accelerate northeast with no development.

An active wave - '96-L' - continues moving west across the Atlantic & is approaching the Eastern Caribbean.  Indications are - & forecast models have generally followed suit - that the wave will remain shallow (poorly organized & weak) & will, therefore, move more west vs. a northward turn.  This is potentially important in the long run.  Hostile shear should keep this wave from strengthening for at least the next several days, but I'm not convinced that '96-L' can't thrive later on.  This is something to watch over or near the Gulf late in the week/next weekend.

Another wave is following '96-L' & has some long term potential as well.  This wave will also likely take a southern route avoiding a persistent weak trough over the Eastern U.S. that might otherwise steer a deeper system to the north.

Model plots for wave '96-L':

The chart below is the upper (500mb) level forecast for Wed., Aug. 7th.  The weak - but still significant & recently persistent - trough over the Eastern U.S. plays a key role in any stronger tropical systems that might try to move west by turning systems more north.  As of right now, Atlantic tropical waves are taking the "low road" .... more southern latitude.

An examination of dust over the Central & Eastern Atlantic shows a pretty heavy area of dust/dry air over the Eastern & Central Atlantic extending to the Eastern Caribbean.  While such dry air can inhibit tropical development initially, once the wave is farther west & out of the dust "cloud" - IF all other conditions are equal - organization/strengthening can occur.  The 2005 hurricane season stands out as a "dusty" Eastern Atlantic but disturbances simply waited to get out of the dust - further to the west - to develop & then "make history".

2019 names..... "Chantal" is next on the Atlantic list (names are picked at random... repeat every 6 years... historic storms are retired (Florence & Michael last year):

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East Atlantic:

Mid & upper level wind shear (enemy of tropical cyclones) analysis (CIMMS). The red lines indicate strong shear of which there is plenty across the Atlantic at the moment:

The Atlantic Basin:

Water vapor imagery (dark blue indicates dry air):

Deep oceanic heat content:

Sea surface temp. anomalies show some "cool" water remaining over the E. Atlantic but avg. to above avg. temps. for much of the rest of the Atlantic Basin.....

SE U.S. surface map:

Surface analysis centered on the tropical Atlantic:

Surface analysis of the Gulf:

Caribbean:

PACIFIC:

Fast weakening "Erick" well southwest of Hawaii is in the process of dissipating while it continues moving W/NW becoming absorbed by a strong upper level trough.  "Flossie" follows & will be near/north of Hawaii early in the week but - again like Erick - quickly weakening with no severe impacts on the islands.

Flossie model plots:

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