TROPICAL DEPRESSION FRED FORECAST SYNOPSIS…ISSUED AUG. 12, 2021…9:10 P.M. EDT


Disclaimer:  This site is not affiliated with the National Hurricane Center, Hurricane Hunters, Storm Prediction Center, or National Weather Service.  ALL forecasts herein are the result of my analysis, and I am solely responsible for the content.  As ALWAYS, follow the National Hurricane Center, National Weather Service, and your local Emergency Management officials for emergency decisions.  In addition, this is strictly a FORECAST OFFICE.  I CANNOT make decisions regarding travel plans, etc.  My purpose, is to provide you the information, based solely on information I analyze, and the accuracy of the information at hand of the time of analysis, so you may make informed decisions.
(T. F. “Storm” Walsh)

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Please be aware, even though I do not post every night, rest assured I am continuously monitoring various areas for any significant weather.  I will be taking Sundays off (family time), unless we have active systems that may be posing a threat (i.e. Tropical, Winter Weather, Coastal Storms, etc.).
STORM WALSH PRE-SEASON FORECAST
TOTAL NAMED STORMS: 17 – 20
TOTAL HURRICANES :        7 – 9
MAJOR HURRICANES:       4 – 5

AVERAGE HURRICANE SEASON:
TOTAL NAMED STORMS: 14
TOTAL HURRICANES:         7
MAJOR HURRICANES:       3

2021 SEASON TOTALS:
TOTAL NAMED STORMS: 6
TOTAL HURRICANES:        1
MAJOR HURRICANES:    0

TOTAL U. S. LANDFALLS: 3

The following is the list of storm names for the 2021 Atlantic Hurricane Season:
Ana Bill Claudette Danny Elsa Fred Grace Henri Ida Julian Kate Larry
Mindy Nicholas Odette Peter Rose Sam Teresa Victor Wanda
As a storm becomes named, I will be marking it in bold red to keep track of the activity for this Atlantic season.

Please note..when we are dealing with multiple systems, they will be listed in order as to the greatest threat to land or the U. S. , to the least threat.

For our friends in the Caribbean and Lesser Antilles, right now, I am unable to conduct a full analysis on both systems.  The NHC has however increased the probability for 95L becoming a tropical cyclone.
two_atl_5d0

A small low pressure system located about 1100 miles east of the 
Lesser Antilles is producing disorganized shower and thunderstorm 
activity primarily west of the center.  However, environmental 
conditions are expected to gradually become more conducive for 
additional development, and a tropical depression is likely to form 
by the weekend. The system is forecast to move generally westward at 
about 20 mph across the tropical Atlantic, reaching portions of the 
Leeward Islands late Saturday or early Sunday, and interests there 
should monitor its progress.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 5 days...high...70 percent.

aal95_2021081218_track_early

Good evening everyone,
Tropical Storm FRED has been downgraded to a depression, after crossing the island of Hispaniola last night and this morning.  To put it in no uncertain terms, FRED got his butt kicked after encountering the 10,000 ft mountains in central Hispaniola.  Satellite loop images this evening show a disorganized, and sheared system.  The COC is noted just to the NW of a flareup of convection.  Water vapor indicates some dry air in the center.  It appears the flareup of convection may be slowly reducing the dry air.  I am not sure at the moment if the convection will continue to build…if it does, this may indciate FRED may be on the way to a slow recovery.  The following are satellite animations from WEATHERNERDS.
GOES 16 IR ANIMATION98395949IR
GEOS 16 VISIBLE ANIMATION98395949VIS
WATER VAPOR ANIMATION43584323
ATLANTIC ANIMATION98395949ATL
AFRICA SATELLITEsat_20210812_2315_animation
As of the 8:00 p.m. EDT intermediate advisory from the NHC, the following was available on FRED.
8:00 PM EDT Thu Aug 12
Location: 21.3°N 75.0°W
Moving: WNW at 7 mph
Min pressure: 1012 mb / 29.88 in
Max sustained: 35 mph
ABOUT 240 MI…385 KM SE OF SOUTHERN ANDROS ISLAND BAHAMAS
ABOUT 485 MI…780 KM ESE OF KEY WEST FLORIDA
Based on current satellite loop imagery, FRED does continue to move to the WNW, and his forward speed has slowed.  Based on analysis of forecast steering layers, this motion should continue during the next 24 – 30 hours.  Thereafter, forecast steering indicates a turn toward the NW should occur.  At around 72 – 84 hours in the period, a more northerly track should occur.  This is shown in the most available track guidance, and the same was noted in analysis of forecast steering layers (850 – 700 mb, and 850 – 500 mb).  Based on this, I currently agree with the NHC forecast track, save any center relocations as FRED tries to recover.  It is noted that central pressure has dropped 2 mb since this afternoon.  Model guidance has taken a shift more toward the west, and if the forecast track pans out, FRED should pass a little further offshore to the west of the Florida coast in a few days.  I will be keeping close tabs on this, in case the forecast steering flow changes over the next 48 – 72 hours.
NHC TRACKING MAP205525_5day_cone_no_line_and_wind
NHC TRACKING MAP (LINKED TO THE NHC INTERACTIVE MAP…CLICK MAP)205525_5day_cone_no_line_and_wind
18Z ATCF GUIDANCE
atcf-fred06l-1628791200-8791200
ECMWF ENSEMBLE GUIDANCE
AL06_2021081212_ECENS_0-120h_large

Maximum sustained winds with FRED are now 35 mph. As mentioned before, satellite imagery indicated convection building to the SE of the center, just on the edge, and in uncertain terms, FRED could be trying to recover.  Analysis of the most recent wind shear map from CIMSS indicated FRED was under 20 kts of westerly shear.  Based on analysis of forecast wind shear maps, wind shear is forecast to remain, until FRED reaches a point near the very northern Bahamas chain, and the Florida straights.  Shear is then forecast to relax, and appears to change to a very favorable upper level environment as far as shear is concerned.  The upper level low over Florida at the moment is forecast to weaken, and a large upper level anticyclone is forecast to develop, just as the system reaches the Florida Keys, and then enters the GOMEX.  You’ll notice this in the ECMWF 200 mb streamline animation.
CIMSS WIND SHEAR MAP94L.SHEAR
GFS WIND SHEAR FORECASTgfs_dl_shear_carib_6gfs_dl_shear_carib_54gfs_dl_shear_carib_72
ECMWF 200 MB STREAMLINE ANIMATIONecmwf-deterministic-caribbean-z200_speed-1628769600-1628769600-1629028800-40
Based on this, the current disorganization of FRED, and possible slower recovery, I have to agree with the NHC intensity forecast.  I will however be monitoring this, and will re-evaluate the situation when I can see how FRED reacts to the changes.  At the moment, I don’t believe FRED will intensify quickly, until it reaches that area just mentioned, based on the high OHC in the area.  This may help fight off any remaining dry air.  In fact, the GFS and ECMWF show improving mid level moisture at that time as 700 – 500 mb relative humidity values are shown to increase.  The last SHIPS diagnostics report indicated this as well.
CURRENT OHC MAPtcheat_swatl_2021081212
NHC INTENSITY FORECAST
INIT 12/2100Z 21.3N 75.3W 30 KT 35 MPH
12H 13/0600Z 22.0N 77.0W 30 KT 35 MPH
24H 13/1800Z 23.0N 79.0W 30 KT 35 MPH
36H 14/0600Z 24.0N 80.6W 35 KT 40 MPH
48H 14/1800Z 25.2N 81.9W 35 KT 40 MPH
60H 15/0600Z 26.4N 83.1W 40 KT 45 MPH
72H 15/1800Z 28.1N 84.1W 45 KT 50 MPH
96H 16/1800Z 31.0N 85.5W 40 KT 45 MPH…INLAND
120H 17/1800Z 33.5N 85.5W 25 KT 30 MPH…INLAND

Tropical Storm watches and warnings are still in effect, and the following information is from the NHC advisories:
235350_current_wind_sm

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Watch is in effect for...
* The Cuban provinces of Ciego de Avila, Camaguey, Las Tunas,
Holguin, and Granma
* The Florida Keys west of Ocean Reef to the Dry Tortugas
* The southwest coast of Florida from Bonita Beach south and east to
Ocean Reef including Florida Bay

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area.

Interests elsewhere in the Bahamas, Cuba, and the southern Florida
Peninsula should monitor the progress of Fred.  Additional watches
and warnings may be required for portions of these areas tonight
and Friday.

For storm information specific to your area in the United States, 
including possible inland watches and warnings, please monitor 
products issued by your local National Weather Service forecast 
office. For storm information specific to your area outside of the 
United States, please monitor products issued by your national 
meteorological service.
HAZARDS AFFECTING LAND
----------------------
Key messages for Fred can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT1, WMO header WTNT41 KNHC and
on the web at www.hurricanes.gov/graphics_at1.shtml?key_messages.

RAINFALL: Fred is expected to produce the following rainfall
amounts:

Over the Turks and Caicos, Cuba and the eastern Bahamas...1 to 3
inches with isolated maximum totals of 5 inches.

Across the western Bahamas...3 to 5 inches, with isolated maximum
totals of 8 inches.

From Friday into Monday, 3 to 6 inches of rain is anticipated across
the Florida Keys, the southern and central Florida Peninsula, and
north towards the Big Bend of Florida, with isolated maximum totals
of 8 inches. Heavy rainfall could lead to areal, urban, and small
stream flooding, and potentially exacerbate ongoing minor to
isolated moderate river flooding.

By early next week, heavy rain and flood impacts could extend into
other portions of the Southeast and into the southern and central
Appalachians and Piedmont.

WIND:  Tropical storm conditions are possible in the watch area in
Cuba tonight through Friday night.  Tropical storm conditions are
possible in the watch area in Florida beginning Friday night.  Wind
gusts to tropical storm force may occur over portions of the
southeastern Bahamas tonight.

SURF:  Swells generated by Fred are expected to spread across
portions of the Bahamas and northern coast of Cuba during the next
couple of days.  These swells could reach the Florida Keys and
southern Florida by early Saturday.  Please consult products from
your local weather office for more details.

205525_key_messages_sm
205525_spanish_key_messages_sm

NWS LOCAL PRODUCTS FOR FRED (CLICK LINK)
https://www.nhc.noaa.gov/text/refresh/index_hls1+shtml/122126.shtml?

The following map will allow to to get information from your NWS office.
NWS WATCH / WARNING DISPLAY (LINKED…CLICK MAP, THEN YOUR AREA)

NWS SAN JUAN, PUERTO RICO LINK
https://www.weather.gov/sju/

WSI DOPPLER RADAR LOOP (LINKED, CLICK RADAR MAP)

RAP RADAR (CLICK IMAGE THEN RADAR SITE)
CARIBBEAN RADAR IMAGES (LINK)
https://www.barbadosweather.org/Composite/kidbuuComposite_Lionel_displayer2.php?Product=Reflectivity&Sector=fullView&Composite=Sabre&ANISP=700&MAPP=1&PlanetOfTheApes=11254

I will continue to monitor FRED for any significant changes to the forecast atmospheric parameters, and intend to update again tomorrow evening.

You may direct any questions by contacting me personally, ANYTIME, at: [email protected]

Have a blessed evening!

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



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