000 WTNT44 KNHC 290246 TCDAT4 Tropical Storm Harvey Discussion Number 35 NWS National Hurricane Center Miami FL AL092017 1000 PM CDT Mon Aug 28 2017 The center of Harvey has been moving east-southeastward over the extreme western Gulf of Mexico this evening. Although there is no deep convection near the center of Harvey, thunderstorm activity has continued to increase well north of the center, along the immediate northwest Gulf Coast and has spread inland over the Greater Houston area, worsening the catastrophic flooding situation. Another band of heavy rainfall is moving inland over portions of southern and southwestern Louisiana. Widespread rainfall totals of 30 to 36 inches have been observed in southeastern Texas and the Houston Metropolitan Area. Storm totals could reach 50 inches in some locations, which would be historic for the area. A NOAA National Ocean Service observing site near Matagorda Bay has continued to report sustained tropical-storm-force winds this evening, and data from this and other nearby stations still support an initial intensity of 40 kt. Given the current structure of the cyclone and the lack of convection near the center, little change in strength is expected while Harvey moves over the northwestern Gulf of Mexico. After landfall in about 36 hours, gradual weakening should occur as the circulation moves farther inland. Harvey has been moving east-southeastward or 120/3 kt. The storm is forecast to turn northeastward, then north-northeastward over the next couple of days as a ridge to the northwest of the system weakens and Harvey is steered around the western side of a ridge over the eastern Gulf of Mexico. The track guidance has shifted slightly eastward and the new NHC track has been adjusted in that direction. Key Messages: 1. Ongoing catastrophic and life-threatening flooding will continue across southeastern Texas. Additional rainfall accumulations of 10 to 20 inches are expected across the upper Texas coast, with isolated storm totals as high as 50 inches. Please heed the advice of local officials. Do not attempt to travel if you are in a safe place, and do not drive into flooded roadways. Refer to products from your local National Weather Service office and the NOAA Weather Prediction Center for more information on the flooding hazard. A summary of rainfall totals compiled by the Weather Prediction Center can be found at: www.wpc.ncep.noaa.gov/discussions/nfdscc1.html 2. The flood threat has spreading farther east into Louisiana. Additional rainfall amounts of 10 to 20 inches are expected in southwestern Louisiana, with rainfall amounts of 5 to 15 inches expected in south-central Louisiana. Rainfall amounts of 5 to 10 inches are expected in southeast Louisiana and coastal Mississippi and Alabama. Please heed the advice of local officials and refer to products from your local National Weather Service office and the NOAA Weather Prediction Center for more information on the flooding hazard in these areas. 3. While Tropical Storm Warnings have been extended eastward along the coast of Louisiana and a Storm Surge Watch has been issued, the impacts of winds and storm surge are expected to be secondary compared to that of the rains. FORECAST POSITIONS AND MAX WINDS INIT 29/0300Z 28.2N 95.3W 40 KT 45 MPH 12H 29/1200Z 28.1N 95.0W 40 KT 45 MPH 24H 30/0000Z 28.5N 94.5W 40 KT 45 MPH 36H 30/1200Z 29.5N 94.0W 40 KT 45 MPH 48H 31/0000Z 30.7N 93.4W 35 KT 40 MPH...INLAND 72H 01/0000Z 33.4N 91.9W 30 KT 35 MPH...INLAND 96H 02/0000Z 35.5N 90.0W 25 KT 30 MPH...INLAND 120H 03/0000Z 38.0N 86.5W 20 KT 25 MPH...POST-TROP/INLAND $$ Forecaster Brown