We now have Tropical Depression Twenty-Five.
000
WTNT45 KNHC 021456
TCDAT5
Tropical Depression Twenty-Five Discussion Number 1
NWS National Hurricane Center Miami FL AL252020
1100 AM EDT Fri Oct 02 2020
Visible satellite images show that cloudiness and showers associated
with the low pressure area over the northwestern Caribbean Sea have
become significantly better organized since yesterday, with
convective banding features becoming prominent. Moreover, low cloud
motions suggest that a closed circulation has become better defined.
Therefore, advisories are being initiated on Tropical Depression
Twenty-Five at this time. The initial intensity estimate is 30 kt
based on Dvorak T-numbers, but an Air Force Reserve Hurricane Hunter
aircraft is scheduled to investigate the system later today to
provide a better intensity estimate. Sea surface temperatures are
very warm, near 30 deg C, and vertical shear should remain low for
at least the next couple of days, so the cyclone is likely to become
a tropical storm by the time it nears the Yucatan Peninsula
tomorrow. The main impediment to strengthening over the next few
days should be the interaction with land. Given the uncertainties
about how far offshore the center will be over the next several
days, the official intensity forecast is conservative.
Since there is still a lot of scatter in the center fixes, the
initial motion estimate, 315/8 kt, is rather uncertain. For the
next couple of days, the system is expected to move northwestward to
north-northwestward on the southwestern edge of a mid-level high
pressure area. This would take the center near or over the
northeastern Yucatan Peninsula. After about 48 hours, the steering
currents are not well-defined and there is considerable spread in
the track models. At this time, it appears the cyclone should move
slowly westward over the latter part of the forecast period in
response to weak ridging over the north-central Gulf of Mexico. The
official forecast is near or a little north of the corrected and
simple model consensus predictions.
Tropical Storm Warnings and Watches have been issued for a portion
of the Yucatan Peninsula.
KEY MESSAGES:
1. The system is expected to produce heavy rainfall that could
result in life-threatening flash flooding over portions of the
Yucatan Peninsula, far western Cuba and well away from the center in
the Mexican states of Campeche, Tabasco, and northern Chiapas.
2. The depression is forecast to become a tropical storm and bring
tropical storm conditions to portions of the Yucatan Peninsula on
Saturday, where a Tropical Storm Warning is in effect.
FORECAST POSITIONS AND MAX WINDS
INIT 02/1500Z 18.1N 84.7W 30 KT 35 MPH
12H 03/0000Z 18.9N 85.6W 30 KT 35 MPH
24H 03/1200Z 19.8N 86.6W 35 KT 40 MPH
36H 04/0000Z 20.6N 87.2W 40 KT 45 MPH...INLAND
48H 04/1200Z 21.4N 87.5W 40 KT 45 MPH...INLAND
60H 05/0000Z 22.0N 87.6W 40 KT 45 MPH
72H 05/1200Z 22.0N 88.2W 45 KT 50 MPH
96H 06/1200Z 21.5N 90.5W 45 KT 50 MPH
120H 07/1200Z 21.5N 92.5W 45 KT 50 MPH
$$
Forecaster Pasch
