Atlantic Hurricane Feed

Tropical Storm Francine Forecast Discussion

Published Date and Time: 2024-09-09 22:31:35



418 
WTNT41 KNHC 100231
TCDAT1

Tropical Storm Francine Discussion Number   6
NWS National Hurricane Center Miami FL       AL062024
1000 PM CDT Mon Sep 09 2024

After strengthening this afternoon, Francine's intensity appears to 
have leveled off for now.  Around 18Z today, microwave images 
indicated that the storm had a closed low-level eyewall and a 
relatively symmetric cloud pattern.  However, an intrusion of dry 
air has caused the inner core convection to degrade.  The Air Force 
and NOAA Hurricane Hunter aircraft have been investigating Francine 
this evening and have found that the maximum winds have changed 
little from earlier and remain around 55 kt.  However, the minimum 
pressure reported from the aircraft has dropped to 992 mb, which 
could indicate that strengthening will resume soon. The outer 
rainbands to the west and northwest of the center are very near the 
coast of northeastern Mexico and extreme southern Texas, and there 
are likely tropical-storm-force winds in those bands.

The storm has been moving slowly north-northwestward or 340 degrees
at 4 kt. A mid-level ridge situated over the southeastern Gulf of
Mexico should cause Francine to continue to move slowly
northwestward to northward just off the coast of northeastern Mexico
through Tuesday morning.  By late Tuesday, a trough over Texas is
expected to approach the system, and the stronger flow between the
trough and the aforementioned ridge should cause a turn to the
northeast with a pronounced increase in forward speed. This motion
should take the cyclone to the Louisiana coast Wednesday afternoon
or evening.  The models are in fairly good agreement on this
scenario, but there is a fair amount of along-track spread or
differences in when the storm reaches the coast.  The NHC track
forecast is similar to the previous one and near the TVCN aid.

Environmental conditions are forecast to remain quite favorable for
strengthening along Francine's path for the next 24 hours, with very
warm ocean waters while remaining in a low wind shear environment.
The SHIPS RII index for rapid intensification over the next 24 hours
has decreased a little due to some dry air in the environment around
Francine.  The NHC intensity forecast is similar to the previous
one, and lies near the high end of the intensity guidance suite.
Just prior to landfall, Francine should encounter increasing
west-southwesterly vertical wind shear, which will likely end the
intensification trend.  Rapid weakening is expected after the storm
moves inland.

An experimental cone graphic that includes inland Hurricane and
Tropical Storm Watches and Warnings in the U.S. is now available on
the NHC website. Due to the time needed to compile the inland watch
and warning information, the experimental cone graphic will not be
available as quickly as the operational cone. Once it is available,
the experimental cone graphic can be found from a red weblink above
the operational cone graphic at
www.nhc.noaa.gov/graphics_at1.shtml?cone#contents. Users are
encouraged to take the experimental product survey found below the
experimental cone.

KEY MESSAGES:

1. There is a danger of life-threatening storm surge for portions
of the Upper Texas and Louisiana coastlines where a Storm Surge
Warning is in effect.  Residents in the warning area should follow
advice, including evacuation orders, given by local officials.

2. Damaging and life-threatening hurricane-force winds are expected
in portions of southern Louisiana Wednesday, where a Hurricane
Warning is in effect. Preparations to protect life and property
should be complete by Tuesday night since tropical storm conditions
are expected to begin within this area early Wednesday.

3. Francine is expected to bring heavy rainfall and the risk of
considerable flash flooding along the coast of northeast Mexico,
the far lower and far upper Texas coasts, much of Louisiana, and
Mississippi into Thursday morning. A risk of flash and urban
flooding exists across portions of the Mid-South from Wednesday
night into Friday morning.


FORECAST POSITIONS AND MAX WINDS

INIT  10/0300Z 24.3N  96.2W   55 KT  65 MPH
 12H  10/1200Z 24.9N  96.0W   65 KT  75 MPH
 24H  11/0000Z 26.2N  95.2W   80 KT  90 MPH
 36H  11/1200Z 27.9N  93.7W   85 KT 100 MPH
 48H  12/0000Z 29.9N  92.2W   75 KT  85 MPH...INLAND
 60H  12/1200Z 32.4N  90.9W   40 KT  45 MPH...INLAND
 72H  13/0000Z 34.6N  90.6W   30 KT  35 MPH...POST-TROPICAL
 96H  14/0000Z 36.6N  90.0W   20 KT  25 MPH...POST-TROPICAL
120H  15/0000Z...DISSIPATED

$$
Forecaster Cangialosi/Hagen




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