000 WTNT24 KNHC 242044 TCMAT4 HURRICANE HARVEY FORECAST/ADVISORY NUMBER 18 NWS NATIONAL HURRICANE CENTER MIAMI FL AL092017 2100 UTC THU AUG 24 2017 CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY... THE HURRICANE WARNING HAS BEEN EXTENDED NORTHEAST OF MATAGORDA TO SARGENT TEXAS. SUMMARY OF WATCHES AND WARNINGS IN EFFECT... A STORM SURGE WARNING IS IN EFFECT FOR... * PORT MANSFIELD TO HIGH ISLAND TEXAS A STORM SURGE WATCH IS IN EFFECT FOR... * SOUTH OF PORT MANSFIELD TEXAS TO THE MOUTH OF THE RIO GRANDE A HURRICANE WARNING IS IN EFFECT FOR... * PORT MANSFIELD TO SARGENT TEXAS A TROPICAL STORM WARNING IS IN EFFECT FOR... * NORTH OF SARGENT TO HIGH ISLAND TEXAS * SOUTH OF PORT MANSFIELD TEXAS TO THE MOUTH OF THE RIO GRANDE A HURRICANE WATCH IS IN EFFECT FOR... * SOUTH OF PORT MANSFIELD TEXAS TO THE MOUTH OF THE RIO GRANDE A TROPICAL STORM WATCH IS IN EFFECT FOR... * SOUTH OF THE MOUTH OF THE RIO GRANDE TO BOCA DE CATAN MEXICO A STORM SURGE WARNING MEANS THERE IS A DANGER OF LIFE-THREATENING INUNDATION...FROM RISING WATER MOVING INLAND FROM THE COASTLINE... DURING THE NEXT 36 HOURS IN THE INDICATED LOCATIONS. FOR A DEPICTION OF AREAS AT RISK...PLEASE SEE THE NATIONAL WEATHER SERVICE STORM SURGE WATCH/WARNING GRAPHIC...AVAILABLE AT HURRICANES.GOV. THIS IS A LIFE-THREATENING SITUATION. PERSONS LOCATED WITHIN THESE AREAS SHOULD TAKE ALL NECESSARY ACTIONS TO PROTECT LIFE AND PROPERTY FROM RISING WATER AND THE POTENTIAL FOR OTHER DANGEROUS CONDITIONS. PROMPTLY FOLLOW EVACUATION AND OTHER INSTRUCTIONS FROM LOCAL OFFICIALS. A HURRICANE WARNING MEANS THAT HURRICANE CONDITIONS ARE EXPECTED SOMEWHERE WITHIN THE WARNING AREA. A WARNING IS TYPICALLY ISSUED 36 HOURS BEFORE THE ANTICIPATED FIRST OCCURRENCE OF TROPICAL-STORM- FORCE WINDS...CONDITIONS THAT MAKE OUTSIDE PREPARATIONS DIFFICULT OR DANGEROUS. PREPARATIONS TO PROTECT LIFE AND PROPERTY SHOULD BE RUSHED TO COMPLETION. A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE EXPECTED SOMEWHERE WITHIN THE WARNING AREA WITHIN 36 HOURS. A STORM SURGE WATCH MEANS THERE IS A POSSIBILITY OF LIFE- THREATENING INUNDATION...FROM RISING WATER MOVING INLAND FROM THE COASTLINE...IN THE INDICATED LOCATIONS DURING THE NEXT 48 HOURS. A HURRICANE WATCH MEANS THAT HURRICANE CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA. A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA. IN ADDITION...INTERESTS IN SOUTHWESTERN LOUISIANA SHOULD CONTINUE TO MONITOR THE PROGRESS OF THIS SYSTEM. HURRICANE CENTER LOCATED NEAR 24.7N 93.9W AT 24/2100Z POSITION ACCURATE WITHIN 15 NM PRESENT MOVEMENT TOWARD THE NORTH-NORTHWEST OR 330 DEGREES AT 9 KT ESTIMATED MINIMUM CENTRAL PRESSURE 976 MB EYE DIAMETER 20 NM MAX SUSTAINED WINDS 75 KT WITH GUSTS TO 90 KT. 64 KT....... 20NE 0SE 0SW 0NW. 50 KT....... 30NE 20SE 20SW 30NW. 34 KT....... 80NE 40SE 30SW 60NW. 12 FT SEAS..120NE 75SE 75SW 75NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 24.7N 93.9W AT 24/2100Z AT 24/1800Z CENTER WAS LOCATED NEAR 24.4N 93.6W FORECAST VALID 25/0600Z 25.5N 94.8W MAX WIND 95 KT...GUSTS 115 KT. 64 KT... 30NE 15SE 10SW 15NW. 50 KT... 50NE 40SE 30SW 40NW. 34 KT...110NE 70SE 50SW 80NW. FORECAST VALID 25/1800Z 26.7N 96.0W MAX WIND 110 KT...GUSTS 135 KT. 64 KT... 35NE 30SE 20SW 30NW. 50 KT... 60NE 50SE 40SW 50NW. 34 KT...130NE 100SE 70SW 100NW. FORECAST VALID 26/0600Z 27.8N 96.7W MAX WIND 105 KT...GUSTS 130 KT. 64 KT... 35NE 30SE 30SW 35NW. 50 KT... 60NE 60SE 50SW 60NW. 34 KT...140NE 110SE 80SW 90NW. FORECAST VALID 26/1800Z 28.5N 97.1W...INLAND MAX WIND 85 KT...GUSTS 105 KT. 50 KT... 50NE 50SE 40SW 40NW. 34 KT...130NE 110SE 80SW 80NW. FORECAST VALID 27/1800Z 28.7N 97.2W...INLAND MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 90NE 70SE 60SW 50NW. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 150 NM ON DAY 4 AND 200 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 28/1800Z 28.5N 96.5W...INLAND MAX WIND 35 KT...GUSTS 45 KT. OUTLOOK VALID 29/1800Z 29.0N 95.0W...OVER WATER MAX WIND 35 KT...GUSTS 45 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 24.7N 93.9W NEXT ADVISORY AT 25/0300Z $$ FORECASTER BERG