Atlantic Basin Tropical Cyclones

Tropical Storm Julia Forecast Discussion


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WTNT43 KNHC 082040
TCDAT3

Tropical Storm Julia Discussion Number  10
NWS National Hurricane Center Miami FL       AL132022
500 PM EDT Sat Oct 08 2022

Satellite images and radar data from San Andres Island show that
convection is starting to fill in to the north of Julia's center, 
with a burst now rotating around the east side of and over the 
core.  Dvorak estimates from TAFB and SAB are now T3.5/55 kt and 
T4.0/65 kt, respectively, and the UW-CIMSS ADT is between 60 and 65 
kt.  Based on these data, Julia's intensity is raised to 60 kt.  
Both NOAA and the Air Force Reserve Hurricane Hunters are scheduled 
to conduct missions in Julia this evening.

Julia may have slowed down just a little bit, and the initial
motion estimate is westward, or 270/15 kt.  Strong ridging over
Florida and the Gulf of Mexico should keep Julia on a relatively
quick westward trajectory during the next couple of days, reaching
the coast of Nicaragua overnight and then moving across the country
on Sunday.  Track model guidance has continued to shift southward,
and there's now nearly unanimous consensus that Julia's center will
remain intact and emerge off the Pacific coast of Nicaragua Sunday
evening.  Julia, or its remnants, are then expected to move
westward, generally parallel to the coasts of El Salvador and
Guatemala Sunday night and Monday.  The new NHC track forecast is
very similar to the previous prediction, except just a touch south
while over the Pacific waters.

Environmental conditions favor strengthening this evening and
tonight before Julia reaches the coast of Nicaragua, especially if
the recent burst of deep convection can remain near or over the
center.  As such, Julia is still forecast to become a hurricane
within the next 12 hours.  After landfall, fast weakening is
expected, but Julia is forecast to be at or near tropical storm
strength when it emerges off the Pacific coast of Nicaragua due to
its fast transit across the country.  Even if it does survive, the
global models generally show the circulation dissipating or
becoming absorbed by a broader area of low pressure associated with
a Gulf of Tehuantepec gap wind event, and that should occur by
Monday night.

Regardless of Julia's track and existence as a tropical cyclone, the
evolving set up is likely to lead to heavy rains over Central
America for several days, which could cause life-threatening flash
floods and mudslides, especially in areas of mountainous terrain.


Key Messages:

1. Julia is forecast to strengthen into a hurricane this evening
or tonight before reaching the coast of Nicaragua.  A Hurricane
Warning remains in effect for portions of the Nicaragua coast and
the islands of Providencia and San Andres. Hurricane-force winds
and a dangerous storm surge are expected in areas where the core of
the system crosses the islands this evening and moves onshore in
Nicaragua tonight.

2. Life-threatening flash flooding and mudslides are expected across
portions of Central America this weekend.  Flash flooding is
possible across the Isthmus of Tehuantepec in Mexico early next
week.

3. Julia is forecast to remain as a tropical storm while it moves
across Central America to the adjacent Pacific waters, and tropical
storm warnings are in effect along the Pacific coasts of Nicaragua,
Honduras, and El Salvador to account for the possibility of
tropical-storm-force winds in those areas late Sunday and Sunday
night.


FORECAST POSITIONS AND MAX WINDS

INIT  08/2100Z 12.6N  81.3W   60 KT  70 MPH
 12H  09/0600Z 12.5N  83.3W   70 KT  80 MPH
 24H  09/1800Z 12.6N  86.0W   40 KT  45 MPH...INLAND
 36H  10/0600Z 12.8N  88.7W   35 KT  40 MPH...OVER WATER
 48H  10/1800Z 13.3N  91.3W   30 KT  35 MPH
 60H  11/0600Z...DISSIPATED

$$
Forecaster Berg



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