ZCZC NFDTCPAT4 ALL TTAA00 KWNH DDHHMM BULLETIN Post-Tropical Cyclone Nicholas Advisory Number 17 NWS Weather Prediction Center College Park MD AL142021 400 AM CDT Thu Sep 16 2021 ...NICHOLAS BECOMES POST-TROPICAL NEAR MARSH ISLAND ALONG THE CENTRAL LOUISIANA COAST... ...FLASH FLOODING REMAINS A POSSIBILITY ACROSS PORTIONS OF THE CENTRAL GULF COAST OVER THE NEXT COUPLE OF DAYS... SUMMARY OF 400 AM CDT...0900 UTC...INFORMATION ---------------------------------------------- LOCATION...29.4N 91.6W ABOUT 140 MI...230 KM SSE OF ALEXANDRIA LOUISIANA ABOUT 60 MI...95 KM SSE OF LAFAYETTE LOUISIANA MAXIMUM SUSTAINED WINDS...25 MPH...35 KM/H PRESENT MOVEMENT...N OR 360 DEGREES AT 2 MPH...4 KM/H MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES WATCHES AND WARNINGS -------------------- Flash Flood Watches are in effect along the central Gulf Coast from portions of southeast Louisiana, across southern Mississippi and Alabama, to the Florida Panhandle. DISCUSSION AND OUTLOOK ---------------------- At 400 AM CDT (0900 UTC), the center of Post-Tropical Cyclone Nicholas was located near latitude 29.4 North, longitude 91.6 West. The post-tropical cyclone is nearly stationary, but is expected to drift slowly north over the next couple days. Maximum sustained winds are near 25 mph (35 km/h) with higher gusts. Additional slight weakening is expected today. The estimated minimum central pressure is 1007 mb (29.74 inches). The center of Nicholas may become ill-defined over the next couple days as it struggles to develop minimal thunderstorm activity near its center. HAZARDS AFFECTING LAND ---------------------- RAINFALL: Nicholas is expected to produce additional rainfall amounts of 2 to 4 inches across the central Gulf coast Friday, with isolated storm totals of 12 inches possible. Flash flooding impacts, especially in urban areas, are possible across these regions. Widespread minor river flooding is expected, while scattered moderate river flooding is possible, across portions of southeastern Louisiana, southern Mississippi, southern Alabama, and the Florida Panhandle. For the latest rainfall reports and wind gusts associated with Tropical Depression Nicholas see the companion storm summary at WBCSCCNS4 with the WMO header ACUS44KWBC or at the following link https://www.wpc.ncep.noaa.gov/discussions/nfdscc4.html NEXT ADVISORY ------------- Next complete advisory at 1000 AM CDT. $$ Forecaster Lamers FORECAST POSITIONS AND MAX WINDS INIT 16/0900Z 29.4N 91.6W 20 KT 25 MPH...POST-TROPICAL 12H 16/1800Z 29.5N 91.8W 15 KT 15 MPH...POST-TROP/REMNT LOW 24H 17/0600Z 30.2N 91.9W 15 KT 15 MPH...POST-TROP/REMNT LOW 36H 17/1800Z 31.3N 92.0W 15 KT 15 MPH...POST-TROP/REMNT LOW 48H 18/0600Z 32.2N 91.8W 15 KT 15 MPH...POST-TROP/REMNT LOW 60H 18/1800Z...DISSIPATED NNNN