000 WTNT41 KNHC 102038 TCDAT1 Tropical Storm Francine Discussion Number 9 NWS National Hurricane Center Miami FL AL062024 400 PM CDT Tue Sep 10 2024 The convection associated with Francine has not changed much in organization during the past six hours. Radar data from the WSR-88D Doppler radar in Brownsville shows good curved banding around the center, but the convection is having trouble persisting, possibly due to continued dry air entrainment. Reports from an Air Force Reserve Hurricane Hunter aircraft prior to 18Z showed that the central pressure had dropped to near 987 mb, and that the maximum 700-mb flight-level winds were 63 kt. Based on these data and satellite intensity estimates from SAB and TAFB, the initial intensity is set at 55 kt. The initial motion is now 035/9 kt. An approaching mid-latitude shortwave trough over Texas should cause the storm to move 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 that time, Francine should turn more northward between the trough and a mid-level ridge over the eastern United States. While there is little change to the track forecast scenario since the last advisory, the track guidance has again shifted to the east, most notably between 12-48 h. Based on this change, the forecast track during that period is again nudged a little to the east. The new track lies just to the left of the various consensus models. Francine has about 24 h to strengthen over warm water before it encounters strong shear near the Louisiana coast. While there remains a possibility that dry air entrainment could continue to reduce the intensification rate, the intensity forecast continues to call for steady to rapid strengthening during this time based on the otherwise favorable conditions, and the forecast peak intensity of 80 kt is at the high end of the intensity guidance. Intensification is expected to stop near or just before landfall, and rapid weakening is expected after landfall. The global models continue to show the remnants of Francine dissipating after 96 h, and the intensity forecast again follows that scenario. 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 the 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 across eastern Louisiana, Mississippi, far southern Alabama and the western Florida Panhandle through Thursday. Flash and urban flooding is probable across the Lower Tennessee Valley and Lower Mississippi Valley Wednesday night into Friday morning. FORECAST POSITIONS AND MAX WINDS INIT 10/2100Z 25.7N 95.0W 55 KT 65 MPH 12H 11/0600Z 26.9N 94.0W 65 KT 75 MPH 24H 11/1800Z 28.9N 92.0W 80 KT 90 MPH 36H 12/0600Z 31.0N 90.6W 55 KT 65 MPH...INLAND 48H 12/1800Z 33.4N 89.8W 30 KT 35 MPH...INLAND 60H 13/0600Z 35.3N 89.8W 25 KT 30 MPH...INLAND 72H 13/1800Z 36.1N 89.8W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 14/1800Z 37.5N 89.5W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 15/1800Z...DISSIPATED $$ Forecaster Beven
Tropical Storm Francine Forecast Discussion
10
Sep