TROPICAL STORM HUMBERTO / INVEST 92 GABRIELLE / DISTURBED WEATHER WESTERN CARIBBEAN FORECAST SYNOPSIS…SEP. 09, 2013…ISSUED 5:00 P.M. EDT…PHFC

Good afternoon!

Tropical Storm Humberto has strengthened slightly, and maximum winds are near 50 mph.  Based on the 5:00 p.m. EDT advisory from the NHC, the following information was posted, and is contained in the NHC Tracking Map:

NHC HUMBERTO TRACKING MAP

TROPICAL STORM HUMBERTO SATELLITE LOOP

Based on updated current and forecast steering layers maps, I have no reason to change forecast track thinking at the moment, as a weakness will protrude down from the Canary islands, and one in the CATL around 45-50W in about 48 hours (NHC now mentions this one in the discussion) and pull Humberto more toward the NNW abruptly.  Based on this, I  concur with the 18Z Dynamic Model Guidance and NHC official track.  NHC track is marked as OFCI:

18Z DYNAMIC MODEL GUIDANCE
18zatcfearlyinvest1bestHUMBERTO

Based on current and forecast wind shear maps, I concur at the moment with the NHC intensity forecast, however, the forecast shear map does indicates a fairly strong 200 mb anticyclone over Humberto in about 10 hours, and remaining over the storm for at least 2 days.  Based on this, and sst’s of 27-29C prior to Humberto reaching sst’s of >26C, I feel he could attain CAT2 status.  Based on the still somewhat tilted nature of the storm, I have backed off somewhat on the possibility of just making CAT3 status prior to cooler sst’s, but not totally willing to discount this given the excellent outflow patter projected.

GFS WIND SHEAR FORECAST

Closer to home, the area if disturbed weather I mentioned this morning, near the Gulf of Honduras has moved little, and convection has diminished since this morning.  However RGB and visible satellite loop imagery does show a cyclonic circulation.

WATL SATELLITE LOOP IMAGERY

Albeit current wind shear values are marginal at this time, the upper level wind map seems to indicate an outflow pattern may be developing.  This may be valid, as the GFS wind shear forecast projects upper level winds to become more conducive in about 36 hours, with a building upper level anticyclone which may follow this disturbed weather WNW into the BOC, where the upper level anticyclone is forecast to become better defined.  Buoy data closet to the area indicated at 3:00 p.m. MLSP of 29.84 in and falling, however this may be just diurnal changes.

UPPER LEVEL WINDS
wg8wvir (1)

NDBC STATION 42057
http://www.ndbc.noaa.gov/station_page.php?station=42057

Based on current and forecast steering, I expect this to move slowly toward the WNW during the next 36-42 hours, before being turned toward the west as the U.S. ridge re-positions further to the west.  Right now, this doesn’t appear to be any threat to the U.S.

I am still monitoring the remnant of Gabrielle for regeneration.  In fact, upper level winds have relaxed somewhat, and a burst of convection is noted in visible and RGB satellite loops, just on the eastern edge of the circulation.  Upper level winds are forecast to become briefly conducive over the next 24 hours, before becoming unfavorable shortly thereafter.

GABRIELLE REMNANT FLOATER LOOP

I will continue to monitor these areas for any significant changes to any forecast parameters.

Have a blessed evening!

T. F. “STORM” WALSH III
GMCS, USCG (ret)
METEOROLOGIST / HURRICANE SPECIALIST
MEMBER WEST CENTRAL FL AMS 
CERTIFIED SKYWARN OFFICIAL STORM SPOTTER (advanced)
CoCoRaHS OBSERVER

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About palmharborforecastcenter

I am a Tropical Forecast meteorologist, providing hurricane forecasts during the Atlantic Hurricane Season. I retired from the U.S. Coast Guard in July of 2001. Meteorology became my passion in high school, and I have continued my educational background in meteorology since 1996, when I undertook the study of Tropical Meteorology. While working toward my degree, I had to unexpectedly withdraw from college due to my oldest sons medical reasons. I do however, meet the educational criteria of the AMS to be recognized as a meteorologist. Studies include, but are not limited to the Navy Aerographers Mate course, Naval METOC meteorology course, Meteorology 2010 Sophomore level course while attending St. Petersburg College, Clearwater, FL., Basic Forecasting course for operational meteorologists from Rapid WX, meteorology institute, a four month meteorological internship, and extensive research on numerous meteorological topics such as the MJO, NAO, satellite imagery interpretation, etc. I have been forecasting Tropical Weather (Tropical Storms and Hurricanes) since 1996, with my main client being three different Coast Guard Commands.
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5 Responses to TROPICAL STORM HUMBERTO / INVEST 92 GABRIELLE / DISTURBED WEATHER WESTERN CARIBBEAN FORECAST SYNOPSIS…SEP. 09, 2013…ISSUED 5:00 P.M. EDT…PHFC

  1. originallt says:

    Thanks Storm, well, looking this morning(Tuesday) looks like Gabrielle has been re-born and will “whack” Bermuda. Hope it doesn’t get too strong before it reaches there.

  2. Not too happy about a lot of activity but sure do appreciate the continuing rain in S. Tx . We really need it ! Is there any chance of all these tropical “waves” turning into something more serious ?
    Saw a frigate-bird near-shore this AM.. We hardly ever see them except when there is BAD weather off-shore! they were right again today. several waves of Thunderstorms coming in!

  3. Monty says:

    Thanks for the evening update Storm. I guess no reason to send anything out just yet. I’m glued to your synopsis and ready to fire it out. Whew…it got busy out there!! It’s nice to know we have you Senior Chief!!

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