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Tropical Storm Lester Discussion Number 4
NWS National Hurricane Center Miami FL EP132022
1000 AM CDT Fri Sep 16 2022
Lester remains a sheared tropical cyclone, with the low-level center
occasionally becoming exposed to the east of the deep convection.
The overall appearance of the storm has changed little since early
this morning, and the latest subjective and objective Dvorak
intensity estimates support keeping the advisory intensity at 35
kt.
The storm has made its anticipated turn to the northwest and is on
on a heading of 310/7 kt. Lester should continue to move in this
direction for the next couple of days with a slight increase in
forward speed by later today as the cyclone is steered within the
flow between a cyclonic gyre to its west and a building ridge over
Texas. The latest NHC forecast track is little changed from the
previous one, and is near the GFS and ECMWF ensemble means. On this
track, the center of Lester should reach the coastline of Mexico by
Saturday afternoon or evening.
Although Lester is within a thermodynamic environment of very high
atmospheric moisture and over warm waters of of 28-29 degrees
Celsius, the moderate (15-20 kt) east-northeasterly shear currently
affecting the cyclone is forecast to persist through landfall.
Therefore, only gradual intensification is expected during that
time. After landfall, Lester should rapidly weaken over the rugged
terrain of western Mexico, and the cyclone is forecast to dissipate
on Sunday. The latest NHC intensity forecast is unchanged from the
previous one and is close to the various intensity consensus aids.
Key Messages:
1. Heavy rains from Lester will reach portions of coastal southern
Mexico by this evening, increasing in coverage and intensity
Saturday and Saturday night, spreading farther west on Sunday. This
rainfall may produce flash and urban flooding, along with possible
mudslides in areas of higher coastal terrain.
2. Tropical storm conditions are expected along the coast of
southern Mexico on Saturday within the Tropical Storm Warning area.
FORECAST POSITIONS AND MAX WINDS
INIT 16/1500Z 13.7N 96.5W 35 KT 40 MPH
12H 17/0000Z 14.4N 97.6W 40 KT 45 MPH
24H 17/1200Z 15.7N 99.1W 45 KT 50 MPH
36H 18/0000Z 17.2N 100.8W 50 KT 60 MPH...ON THE COAST
48H 18/1200Z 18.7N 102.7W 30 KT 35 MPH...INLAND
60H 19/0000Z...DISSIPATED
$$
Forecaster Latto
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