Track:
https://www.nhc.noaa.gov/refresh/graphics_at3+shtml/?cone#contents
Satellite:
https://www.star.nesdis.noaa.gov/GOES/floater.php?stormid=AL282020
Track remains uncertain.
Tropical Depression Twenty-Eight Discussion Number 1
NWS National Hurricane Center Miami FL AL282020
500 PM EDT Sat Oct 24 2020
Satellite imagery and NOAA Hurricane Hunter aircraft data indicate
that the broad area of low pressure that NHC has been following for
the past couple of days has consolidated enough to be considered a
tropical depression. GOES-16 1-minute data shows the center pretty
clearly, with a new area of convection close by, and a minimum
pressure of 1005 mb was reported by the aircraft in that area. The
surface winds were generally fairly light within about a degree of
the center, but data from the plane supports a 25-kt initial
intensity.
The tropical depression hasn't been moving much, but recently it has
started at least drifting toward the north-northwest. A shortwave
trough moving across the southeastern United States should keep the
cyclone in a rather weak steering pattern during the next day or so,
with only a northwest drift anticipated. Mid-level ridging should
build over the northern Gulf of Mexico on Monday, forcing the
depression to move faster to the west-northwest toward the Yucatan
Peninsula or Channel. The ridge shouldn't last too long, however,
with a substantial upper-level low forecast to eject out of the
southwestern United States in a few days, causing the tropical
cyclone to sharply turn to the north and northeast on Wednesday.
The guidance isn't in very good agreement, and these types of trough
ejection scenarios can have significant timing differences. At
this time, the NHC track forecast leans a little more on the global
models than the regional hurricane models, and is just west of the
model consensus.
While the large-scale shear is fairly light at the moment, the low-
and mid-level circulations of the depression are not well-aligned.
Thus, it might take some time for the system to strengthen despite
low shear and very warm waters. In a day or two, the depression
will likely have a structure that supports a faster rate of
strengthening, and the intensification rate is increased while the
cyclone is near the Yucatan. Although the forecast shows the
system reaching hurricane strength in the southern Gulf of Mexico,
this is rather uncertain given the potential land interaction and
only a narrow area of favorable upper-level winds. A combination of
cooler shelf waters and increasing shear will likely weaken the
cyclone below hurricane strength as it approaches the northern Gulf
Coast. However, strong tropical storms can still produce significant
storm surge, rainfall, and wind impacts, and residents in this
region will yet again need to monitor another tropical cyclone
moving northward across the Gulf.
KEY MESSAGES:
1. The depression is forecast to strengthen to a tropical storm
Sunday and could bring tropical storm conditions to extreme western
Cuba on Monday, where a Tropical Storm Watch is in effect. There is
also a risk of tropical storm conditions in the northern Yucatan
Peninsula of Mexico Monday night and Tuesday.
2. Through Wednesday, heavy rainfall is expected across portions of
central and western Cuba, the Cayman Islands, Jamaica, the northeast
Yucatan peninsula of Mexico, southern Florida and the Keys. This
rainfall may lead to flash flooding in urban areas.
3. The system is forecast to approach the northern Gulf Coast as a
tropical storm on Wednesday, and could bring storm surge, rainfall,
and wind impacts to areas from Louisiana to the Florida Panhandle.
Residents in these areas should monitor the progress of the
depression and updates to the forecast.
FORECAST POSITIONS AND MAX WINDS
INIT 24/2100Z 18.7N 83.0W 25 KT 30 MPH
12H 25/0600Z 19.0N 83.2W 30 KT 35 MPH
24H 25/1800Z 19.5N 83.5W 35 KT 40 MPH
36H 26/0600Z 20.1N 84.2W 40 KT 45 MPH
48H 26/1800Z 20.9N 85.6W 45 KT 50 MPH
60H 27/0600Z 22.0N 87.5W 55 KT 65 MPH
72H 27/1800Z 23.4N 89.4W 65 KT 75 MPH
96H 28/1800Z 27.5N 91.0W 55 KT 65 MPH
120H 29/1800Z 35.5N 84.5W 25 KT 30 MPH...POST-TROP/EXTRATROP
$$
Forecaster Blake
Tropical Depression Twenty-Eight Advisory Number 1
NWS National Hurricane Center Miami FL AL282020
500 PM EDT Sat Oct 24 2020
...2020 PRODUCES YET ANOTHER TROPICAL DEPRESSION...
...TROPICAL STORM WATCH ISSUED FOR PART OF WESTERN CUBA...
SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...18.7N 83.0W
ABOUT 255 MI...405 KM SSE OF THE WESTERN TIP OF CUBA
ABOUT 280 MI...455 KM ESE OF COZUMEL MEXICO
MAXIMUM SUSTAINED WINDS...30 MPH...45 KM/H
PRESENT MOVEMENT...NNW OR 345 DEGREES AT 2 MPH...4 KM/H
MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:
The government of Cuba has issued a Tropical Storm Watch for the
province of Pinar del Rio.
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
A Tropical Storm Watch is in effect for...
* Pinar del Rio Cuba
A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.
Interests in the Yucatan Peninsula should monitor the progress of
the depression.
For storm information specific to your area, please monitor
products issued by your national meteorological service.
DISCUSSION AND OUTLOOK
----------------------
At 500 PM EDT (2100 UTC), the center of Tropical Depression
Twenty-Eight was located near latitude 18.7 North, longitude 83.0
West. The depression is moving toward the north-northwest near 2
mph (4 km/h), and this motion is expected to continue through early
Sunday. The system should gradually turn toward the west-northwest
with a faster forward speed by Monday. On the forecast track, the
center of the depression is anticipated to remain south of Cuba
tomorrow and approach the Yucatan Channel or Yucatan Peninsula late
Monday before emerging into the southern Gulf of Mexico on Tuesday.
Maximum sustained winds are near 30 mph (45 km/h) with higher gusts.
Slow strengthening is forecast during the next 72 hours, and the
system is expected to become a tropical storm on Sunday and could
become a hurricane over the southern Gulf of Mexico on Tuesday.
The estimated minimum central pressure based on NOAA Hurricane
Hunter aircraft data is 1005 mb (29.68 inches).
HAZARDS AFFECTING LAND
----------------------
Key messages for the depression can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT3 and WMO header WTNT43 KNHC.
RAINFALL: Across portions of central and western Cuba, the Cayman
Islands, Jamaica, the northeast Yucatan Peninsula of Mexico,
southern Florida and the Florida Keys, storm total rainfall of 4
to 8 inches with local amounts of 12 inches are possible through
Wednesday.
WIND: Tropical-storm conditions are possible in the watch area
on Monday.
NEXT ADVISORY
-------------
Next intermediate advisory at 800 PM EDT.
Next complete advisory at 1100 PM EDT.
$$
Forecaster Blake
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