TROPICAL WEATHER OUTLOOK FORECAST SYNOPSIS…ISSUED AUG. 01, 2015…6:25 P.M. EDT

SEVERE WEATHER THREAT: SLIGHT
TROPICAL STORM FORMATION:  MONITORING

ALL forecasts contained on this site,  are based on my analysis and knowledge of various forecast tools, including information contained in NHC products, and are not copies from any other entity.

*NOTE: In the TROPICAL STORM FORMATION line above, probabilities are for during the next 5 day period.  My personal probability will be listed as either NONE, MONITORING or PROBABLE.  This does not necessarily mean something will develop, but that certain forecast conditions are likely to be present, favoring development.  Once NHC products become available, then the appropriate probability and percentage will be used.

Please refer to the link for the Storm Prediction Center in the box at the top of the page, just below the Hurricane Hunter graphics.

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Current Storm Total for 2015:

TOTAL STORMS: 3
HURRICANES: 0
INTENSE HURRICANES: 0
U.S. LANDFALLS: 2

StormW Seasonal Forecast:

TOTAL STORMS:             8
HURRICANES:                   3
INTENSE HURRICANES: 1

Given that the current El Nino is rivaling the 1997 event, and that the vertical instability is well below normal in the Atlantic, along with the premise of continued shear over the Caribbean sea, I have decided to revise my seasonal forecast, which is noted above.

Good evening everyone!

INVEST 94L (located near 40W) from the other day has pretty much dissipated, and has been dropped by the NHC.  Drier air and subsidence were pretty much the main factors in the demise.

94L FLOATER IMAGE LOOP
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CATL WATER VAPOR LOOP IMAGE
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Close to home, cloudiness and showers over the NE portion of the GOMEX are associated with a stationary front.  The frontal overlay indicated a 1011 mb low along the front.  Satellite loop imagery indicates some cyclonic turning in the cloud field near the Florida Big Bend region.

GOMEX SATELLITE LOOP IMAGERY
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Vorticity maps indicate an increase in vorticity at the 925 mb level in the past few hours over the north portion of the Big Bend area, and a more compact area at 850 mb over the southern part of the Big Bend region over the past few hours.

925 MB VORTICITY
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850 MB VORTICITY
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Upper level winds are not really conducive for development, and models do not indicate any development from this area.  However, I am monitoring the area over the next 72 hours, as wind shear does not affect baroclinic systems in the way it would affect a tropical system.

Elsewhere, I am monitoring the area in the EATL between 20W and 30W.  A tropical wave located near 25W appears to have become sightly better organized in the last couple frames of satellite loop imagery, albeit convection is very limited.  Albeit upper level winds are marginal at this time, the current wind shear forecast suggests upper level winds could improve slightly over the next 2 – 3 days.  If upper level winds relax enough, we could see some slight development of the area, although it would be very slow to occur.  The global models indicate we could see a couple of waves develop weak closed lows over the next 10 days or so, but nothing of any real development.  The GFS indicates a closed low sitting under a developing upper level anticyclone in 6 days, so slow development within the monsoon trof cannot be ruled out.  However if the dry air problem continues, I  wouldn’t look for anything worth while.  Who knows, it could even be toward the last week of this month, before we see anything that might have a chance at surviving the trek across the Atlantic.

EATL SATELLITE LOOP IMAGERY
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RAMSDIS CIRA METEOSAT LOOP IMAGERY
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GFS 200 MB STREAMLINE FORECAST 144 HOURS
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Some of the problem we have been witnessing is, as these waves first exit the African continent, they move over an area with warmer SST anomalies, to which moisture and more lift is available.  The SAL satellite shot from today, does indicate some African dust over the areas where INVEST 94L had just traveled.  A couple of problems is, as these waves approach and encounter the area at and past 40W longitude, much cooler SST anomalies prevail.  I have 2 different anomaly maps for you.  The first shows the anomalies.  The second, I have drawn blue lines around the warmer anomalies, and brown around the cooler.  The blue lines represent where the most “net lift” is located.  This is where rising air would be located.  The brown line would tend to indicate where sinking air would be located.  Since the warmer areas are allowing air to rise, as this air rises, it spreads out, cools, and begins to sink.  Thus, the sinking air would have a tendency to be located over the area where SST anomalies are much cooler, as the much cooler anomalies indicate an area where there is no rising air, or “lift”  Sinking air is known as subsidence, which dries out the atmosphere around it.  If you look at the water vapor loop at the beginning of the synopsis, the black and orange areas indicate dry air, SAL, or where sinking air would be located.  Now that I’ve gone over that, you can note the lack of vertical instability, in the Atlantic…now you know why.  Along with the cooler anomalies, SST’s are below normal or average.  The magic number for cyclone development lies at 26.5C.

SAL TRUE COLOR SATELLITE VIEW
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SST ANOMALY MAP 1
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SST ANOMALY MAP 2
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TROPICAL ATLANTIC SST TIMELINE
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TROPICAL ATLANTIC VERTICAL INSTABILITY
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Tropical Storm formation is not expected during the next 7 days.

Have a blessed evening!

T. F. “STORM” WALSH III
GMCS, USCG (ret)
METEOROLOGIST / HURRICANE SPECIALIST / SEVERE WEATHER SPECIALIST MEMBER WEST CENTRAL FLORIDA AMS
CoCoRAHS OBSERVER  

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