000 WTNT44 KNHC 150235 TCDAT4 Tropical Depression Nicholas Discussion Number 12 NWS National Hurricane Center Miami FL AL142021 1000 PM CDT Tue Sep 14 2021 Satellite imagery, radar data, and surface observation indicate that the center of Nicholas is over the Beaumont/Port Arthur area of southeastern Texas. The cyclone is currently comprised of a large swirl of low- to mid-level clouds and showers, with a few patches of deep convection well removed from the center. The initial intensity of 30 kt is based on a combination of Doppler radar data and surface obs, and these winds are mainly over water to the southeast of the center. Nicholas should continue to weaken due to strong shear, dry air entrainment, and land interaction, and the cyclone is forecast to degenerate to a remnant low after 24 h and dissipate completely by 72 h. It should be noted that some of the track guidance models show enough south of east motion to bring the center back over the Gulf of Mexico in a day or two. However, even if this should occur the shear and dry air should prevent any re-development. The initial motion is 060/5. While there is some spread in the guidance, it generally agrees on a slow eastward motion for 36 h or so, followed by a northward drift. The new forecast track has only minor changes from the previous track. Although the winds associated with Nicholas are subsiding, due to the forecast slow motion, heavy rainfall and a significant flash flood risk will continue along the Gulf Coast for the next couple of days. The is the last advisory on Nicholas issued by the National Hurricane Center. Future information on this system can be found in Public Advisories issued by the Weather Prediction Center beginning at 4 AM CDT, under AWIPS header TCPAT4, WMO header WTNT34 KWNH, and on the web at http://www.wpc.ncep.noaa.gov. Key Messages: 1. Heavy rainfall will impact areas across southern and central Louisiana, southern Mississippi, far southern Alabama, and the western Florida Panhandle through early Friday. Significant rainfall amounts are expected, potentially resulting in areas of life-threatening flash and urban flooding across these areas. Widespread minor to isolated moderate river flooding is also possible. 2. Storm surge inundation along the coasts of upper Texas and southwestern Louisiana will diminish tonight. 3. Wind gusts to tropical-storm force are possible for a few more hours along portion of the Louisiana and upper Texas coasts. FORECAST POSITIONS AND MAX WINDS INIT 15/0300Z 30.0N 94.1W 30 KT 35 MPH 12H 15/1200Z 30.2N 93.6W 25 KT 30 MPH...INLAND 24H 16/0000Z 30.2N 92.9W 25 KT 30 MPH...INLAND 36H 16/1200Z 30.4N 92.6W 20 KT 25 MPH...POST-TROP/REMNT LOW 48H 17/0000Z 30.9N 92.6W 15 KT 15 MPH...POST-TROP/REMNT LOW 60H 17/1200Z 31.5N 92.6W 15 KT 15 MPH...POST-TROP/REMNT LOW 72H 18/0000Z...DISSIPATED $$ Forecaster Beven