Tropical Storm Francine Forecast Discussion Number 8

By | September 10, 2024

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WTNT41 KNHC 101449
TCDAT1

Tropical Storm Francine Discussion Number   8
NWS National Hurricane Center Miami FL       AL062024
1000 AM CDT Tue Sep 10 2024

Satellite imagery and data from the WSR-88D Doppler radar in 
Brownsville indicate that the central core of Francine has become 
better organized, with the development of a central dense overcast 
and increased convective banding near the center.  In addition, 
reports from NOAA and Air Force Reserve Hurricane Hunter aircraft 
show that the central pressure has fallen to around 988 mb. However, 
these developments have not yet resulted an increase in wind speed, 
as the aircraft-reported winds still support an intensity near    
55 kt this advisory.

After meandering last night, Francine is now moving 
north-northeastward with an initial motion of 020/7 kt.  An 
approaching mid-latitude shortwave trough over Texas should cause 
the storm to turn northeastward at a faster forward speed during the 
next 24-36 h, and this motion should bring the center to the 
Louisiana coast sometime Wednesday afternoon or evening.  After 
landfall, Francine should turn more northward between the trough and 
a mid-level ridge over the eastern United States.  The track 
guidance is generally in good agreement with this scenario. However, 
there has been an eastward shift of the guidance since the last 
advisory, and thus the new forecast track is also shifted eastward.  
In response to this eastward shift in track and southeastern wind 
radii, the hurricane warning in Louisiana was extended eastward at 
12Z, and this advisory has new tropical storm warnings and watches 
for the coasts of Mississippi and Alabama.

Francine has about 24-30 h to strengthen over warm water before it 
encounters strong shear near the Louisiana coast.  While there is a 
possibility that dry air entrainment could reduce the 
intensification rate, the intensity continues to call for steady to 
rapid strengthening during this time based on the otherwise 
favorable conditions.  While it is not explicitly shown in the 
latest forecast, the cyclone could reach a peak intensity near 85 kt 
between the 24 h point and landfall.  Intensification is expected to 
stop before landfall, and rapid weakening is expected after 
landfall.  The global models show the remnants of Francine 
dissipating after 96 h, and the intensity forecast follows that 
scenario. Overall, the intensity forecast is at the upper edge of 
the intensity guidance.

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, Louisiana, and Mississippi 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 tonight, 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 and urban flooding for far northeast Mexico into 
the far southern coast of Texas today and across much of Louisiana 
and Mississippi through Thursday.  Flash and urban flooding is 
probable across the Mid-South Wednesday night into Friday morning.


FORECAST POSITIONS AND MAX WINDS

INIT  10/1500Z 24.9N  95.6W   55 KT  65 MPH
 12H  11/0000Z 26.0N  94.8W   65 KT  75 MPH
 24H  11/1200Z 27.8N  93.2W   80 KT  90 MPH
 36H  12/0000Z 29.9N  91.3W   75 KT  85 MPH...INLAND
 48H  12/1200Z 32.2N  90.4W   40 KT  45 MPH...INLAND
 60H  13/0000Z 34.6N  90.1W   30 KT  35 MPH...INLAND
 72H  13/1200Z 35.8N  90.1W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  14/1200Z 37.0N  90.0W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  15/1200Z...DISSIPATED

$$
Forecaster Beven

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