INVEST 94L FORECAST SYNOPSIS…SPECIAL UPDATE…ISSUED JUL. 29, 2015…7:10 P.M. EDT

SEVERE WEATHER THREAT: MARGINAL
TROPICAL STORM FORMATION:  LOW (30%)

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!

Analysis of satellite loop floaters indicates INVEST 94L has become slightly better organized this evening.

INVEST 94L FLOATER SATELLITE LOOP IMAGERY
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RAMSDIS METEOSAT FLOATER IMAGERY LOOP
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Albeit convection had diminished over the past few hours, the overall cloud structure has improved slightly.  Based on information contained in the 18Z ATCF FTP product, the following was available on INVEST 94L:

Location: 12.1°N 22.6°W
Moving: W at 15 mph
Min pressure: 1010 mb / 29.83 in
Max sustained: 25 mph

The NHC has increased the probability of cyclone formation to (30%) during the next 5 days.

NHC 5 DAY GTWO
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The systems continues to move toward the west, at around 15 mph.  Based on the updated steering layers forecast, valid 00Z this evening, I expect this general motion to continue during the next 48-72 hours, before moving on a more north of due west track.  Based on this forecast, which would mimic the NHC TWO GRAPHIC, I prefer the current track of the HWFI model guidance at this time, as the TVCA – TVCN consensus models have not put out a solution as of my analysis.

ATCF 18Z DYNAMIC MODEL GUIDANCE
INVEST94L 18Z DYNAMIC
Analysis of various parameters around the system indicate water vapor may have improved slightly over and around the system, albeit some slightly drier air in areas near the system are noted.  Wind shear values, and the 200 mb pattern have become somewhat more conducive since this morning.  This, combined with ample TPW, and SST’s of 27-28C around and ahead of the system, have most likely aided in the slightly improved structure.  Although very dry air is out ahead of the path, it is possible that if INVEST 94L can remain in the monsoon trof, and continue to have strong intermittent convection develop, it could throw enough moisture into the mid levels for it to survive.  Albeit slim, it is possible.

INVEST 94L WATER VAPOR LOOP
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INVEST 94L SHEAR ENVIRONMENT
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INVEST 94L TPW (TOTAL PRECIPITABLE WATER)
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INVEST 94L SST
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As stated about the recent shear environment, this has also created a slight change in the forecast shear, in that if one follows the current dynamic steering guidance, which places the INVEST at or about 42-45W longitude at the end of the 5 day forecast period, the most recent zonal shear forecast (12Z…18Z was not yet available)  indicates very low to no zonal shear over the area, with upper level wind streamlines resembling the upper pattern at the moment.  Should the upper level winds play out as forecast, and save any extreme dry air intrusion, the possibility could exist for the development of a depression, which would be very slow to occur.  The more reliable intensity models keep this just below, or at minimal tropical storm status.  Again, this would be based solely on further improvement of surrounding conditions.  Based on my analysis, I agree with the NHC 30% probability of cyclone formation during the next 5 days.

GFS ZONAL SHEAR FORECAST 120 HOURS
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PRELIMINARY INTENSITY FORECAST
INVEST94L 18Z INTENSITY

I will continue to monitor this area for any significant changes during the next 48-72 hours.

I work the next 2 days, so I may not have another update until Saturday.

Elsewhere, 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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