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Tropical Storm Elsa Discussion Number 18
NWS National Hurricane Center Miami FL AL052021
500 PM EDT Sun Jul 04 2021
Elsa continues to exhibit some well-defined convective banding
features over the northern and eastern portions of the circulation.
Dvorak current intensity estimates from TAFB and SAB are 45 and 55
kt respectively,so the advisory intensity remains at 50 kt.
Although the cirrus-level outflow over the area looks fairly
impressive, the SHIPS output diagnoses about 20 kt of vertical
shear over the cyclone, which may be inhibiting strengthening.
Another negative factor could be blockage of the low-level inflow
by the land masses surrounding the cyclone.
The storm has turned toward the northwest, and the initial motion
estimate is now 310/12 kt. There is little change to the track
forecast reasoning from the previous advisory package. Elsa should
move around the western periphery of a mid-level subtropical high
pressure area during the next 3 days or so. Thereafter, the
system should accelerate northward to northeastward over
the eastern United States and the northwest Atlantic. No
significant changes have been made to the NHC track forecast, which
remains close to the simple and correct model consensus solutions.
Some strengthening could occur as the storm approaches the south
coast of Cuba and although not explicitly shown in the official
forecast, Elsa could strengthen to near 60 kt before landfall in
that country. Over the eastern Gulf of Mexico, southwesterly shear
is expected to limit strengthening. The official intensity
forecast remains on the high side of the numerical model guidance.
1. Widespread heavy rain will continue to affect portions of Jamaica
tonight where isolated to scattered flash flooding and mudslides
will be possible. Heavy rain will then impact the Cayman Islands
and Cuba through Monday resulting in significant flooding and
mudslides over Cuba. As Elsa approaches the Florida Keys, Florida
Peninsula, and coastal Georgia Monday through Wednesday, heavy
rainfall may result in isolated flash, urban, and minor river
2. Tropical storm conditions and a dangerous storm surge are
expected with hurricane conditions possible in portions of eastern
Cuba tonight. Tropical storm conditions are expected in portions
of central and western Cuba tonight and Monday, and will spread
into portions of the Florida Keys by late Monday.
3. Tropical Storm and Surge Surge Watches are in effect for
portions of the west coast of the Florida peninsula where tropical
storm conditions and a dangerous storm surge are possible beginning
as early as Monday night and continuing into Tuesday.
4. There is a risk of tropical storm conditions, storm surge,
and rainfall impacts along the remainder of the Florida Peninsula
Tuesday night through Wednesday and the coasts of Georgia and the
Carolinas Wednesday and Thursday.
FORECAST POSITIONS AND MAX WINDS
INIT 04/2100Z 19.8N 77.9W 50 KT 60 MPH
12H 05/0600Z 21.1N 79.4W 55 KT 65 MPH
24H 05/1800Z 22.7N 81.2W 50 KT 60 MPH...INLAND
36H 06/0600Z 24.2N 82.4W 50 KT 60 MPH...OVER WATER
48H 06/1800Z 25.8N 83.0W 50 KT 60 MPH
60H 07/0600Z 27.9N 83.0W 50 KT 60 MPH
72H 07/1800Z 30.5N 82.3W 30 KT 35 MPH...INLAND
96H 08/1800Z 34.9N 78.0W 30 KT 35 MPH...INLAND
120H 09/1800Z 40.0N 69.0W 35 KT 40 MPH...OVER WATER