• Talking the Tropics With Mike: Atlantic tropical waves continue moving west/northwest

    By: Michael Buresh

    Updated:

    Aug. 2, 2019 - The "Buresh Bottom Line": Always be prepared!.....First Alert Hurricane Survival Guide... City of Jacksonville Preparedness Guide... Georgia Hurricane Guide.  

    STAY INFORMED: Get the * FREE * First Alert Weather app

    FREE NEWS UPDATES, ALERTS: Action News Jax app for Apple | For Android

    WATCH "Surviving the Storm"

    READ the First Alert Hurricane Center "Survival Guide"

    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.

    ATLANTIC BASIN:

    A weak tropical wave continues it's journey northward near & just off the east coast of Florida making the bend around the western edge of the Bermuda high over the Central Atlantic.  No significant development of this wave will occur but tropical moisture will continue to stream northward aiding the heavy rain threat across Florida northward all the way to the Carolina's. The wave will turn northeast & accelerate out over the open Atlantic Sunday into early next week.  BOTTOM LINE: a weak tropical wave (we see this during EVERY hurricane season!) will be in the vicinity of Fl. through early Sunday.  Any local / Florida impacts would be an even greater increase in heavy rain in what is a typically wet time of year.

    An active wave - '96-L' - continues moving west across the Central Atlantic.  Little short term development is expected but something to keep an eye on in the longer run.  Between the 5th & 10th of August, the wave should be approaching the Northeast Caribbean &/or SW Atlantic with potentially more favorable conditions to organize.  This wave should be fairly close to the Bahamas - & east of Fl. - approximately Aug. 7 - 9th rounding the western edge of the Bermuda high but potentially within a fairly high shear regime.  Still early, but I would not be surprised if this wave manages to become "Chantal" before atmospheric conditions become particularly hostile.  Key in the future long term movement will be a recently persistent upper level trough over the Eastern U.S. + the exact positioning of the Bermuda High.  It should be noted that a weaker, more shallow system will likely have the potential to get farther west which then become more problematic IF intensification then follows.  Forecast models have been inconsistent - to say the least - on the development of this wave but it needs to be carefully monitored.

    Another wave is closely following '96-L' & has some long term potential as well.  This wave will be under virtually the same steering mechanisms as '96-L' & will need to be watched too.

    Model plots for wave '96-L':

    Radar imagery courtesy S. Fl. Water Management District:

    Rainfall forecast for the next 3 days:

    The chart below is the upper (500mb) level forecast for next Wed., Aug. 7th.  The weak - but still significant & recently persistent - trough over the Eastern U.S. is what will help guide the weak Florida wave north then northeast off the coast then over the Atlantic through early next week & may also play an important role in the eventual track of the Eastern Atlantic wave.

    An examination of dust over the Central & Eastern Atlantic shows a pretty heavy area of dust/dry air over the Eastern & Central Atlantic - typical for this time of year.  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.

    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):

     

    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:

     

    The East & now Central Pacific remains active.  Fast weakening "Erick" will stay well south of Hawaii but  some rough surf will result on the south-facing beaches.  "Flossie" follows & will be near/north of Hawaii early next week but - again like its predecessor - quickly weakening.

    Flossie model plots:

    Next Up: