| It's already catastrophic and it's far from over. Track: http://www.nhc.noaa.gov/refresh/graphics_at4+shtml/?cone Short Range Radar: https://www.wunderground.com/radar/radblast.asp?ID=hgx&type=N0R&num=12&delay=50&showlabels=1&showstorms=1&lightning=1 Long Range Radar: https://www.wunderground.com/radar/radblast.asp?ID=hgx&type=N0Z&num=12&delay=50&showlabels=1&showstorms=1&lightning=1 Floater: http://www.ssd.noaa.gov/PS/TROP/floaters/09L/09L_floater.html Tropical Storm Harvey Advisory Number 28 NWS National Hurricane Center Miami FL AL092017 400 AM CDT Sun Aug 27 2017 ...HARVEY CAUSING CATASTROPHIC FLOODING IN SOUTHEASTERN TEXAS... SUMMARY OF 400 AM CDT...0900 UTC...INFORMATION ---------------------------------------------- LOCATION...29.2N 97.7W ABOUT 50 MI...80 KM ESE OF SAN ANTONIO TEXAS ABOUT 95 MI...155 KM NW OF PORT OCONNOR TEXAS MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H PRESENT MOVEMENT...SSW OR 200 DEGREES AT 1 MPH...2 KM/H MINIMUM CENTRAL PRESSURE...998 MB...29.47 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: The Tropical Storm Warning south of Port O'Connor has been discontinued. The Storm Surge Warning south of Port O'Connor has also been discontinued. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Storm Surge Warning is in effect for... * Port O'Connor to Sargent Texas A Tropical Storm Warning is in effect for... * Port O'Connor to Sargent Texas A Storm Surge Warning means there is a danger of life-threatening inundation from rising water moving inland from the coastline 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. For storm information specific to your area, including possible inland watches and warnings, please monitor products issued by your local National Weather Service forecast office. DISCUSSION AND 48-HOUR OUTLOOK ------------------------------ At 400 AM CDT (0900 UTC), the center of Tropical Storm Harvey was located near latitude 29.2 North, longitude 97.7 West. Harvey is moving toward the south-southwest near 1 mph (2 km/h), and a slow southeastward to east-southeastward motion is expected over the next couple of days. On the forecast track, the center will remain inland or move very near the coast of southeastern Texas through Monday. Maximum sustained winds are near 45 mph (75 km/h) with higher gusts. Some weakening is forecast during the next 48 hours, and Harvey is likely to become a tropical depression by tonight. Tropical-storm-force winds extend outward up to 60 miles (95 km) from the center. An NOS site near the entrance to Matagorda Bay recently reported sustained winds of 40 mph (65 km/h) with a gust to 53 mph (85 km/h). The estimated minimum central pressure is 998 mb (29.47 inches). HAZARDS AFFECTING LAND ---------------------- RAINFALL: Harvey is expected to produce additional rain accumulations of 15 to 25 inches over the middle and upper Texas coast through Thursday. Isolated storm totals may reach around 40 inches in this area. Rainfall of this magnitude will cause catastrophic and life-threatening flooding. Elsewhere during the same time period, Harvey is expected to produce total rain accumulations of 5 to 15 inches farther south toward the lower Texas coast, farther west toward the the Texas Hill Country, and farther east through southwest and central Louisiana. A list of rainfall observations compiled by the NOAA Weather Prediction Center can be found at: www.wpc.ncep.noaa.gov/discussions/nfdscc1.html STORM SURGE: The combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. The water is expected to reach the following heights above ground if the peak surge occurs at the time of high tide... Port Aransas to Port O'Connor...1 to 3 ft Port O'Connor to Sargent...2 to 4 ft Sargent to High Island including Galveston Bay...1 to 3 ft High Island to Morgan City...1 to 2 ft The deepest water will occur along the immediate coast near the area of onshore winds, where the surge will be accompanied by large and destructive waves. Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances. For information specific to your area, please see products issued by your local National Weather Service forecast office. WIND: Tropical storm conditions are occurring in an area near the center and over portions of the tropical storm warning area along the coast. These conditions are likely to persist through this morning. SURF: Swells generated by Harvey affecting the coasts of Texas and Louisiana should subside through this morning. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. TORNADOES: A few tornadoes are possible today and tonight near the middle and upper Texas coast into far southwest Louisiana. NEXT ADVISORY ------------- Next intermediate advisory at 700 AM CDT. Next complete advisory at 1000 AM CDT. $$ Forecaster Pasch Tropical Storm Harvey Discussion Number 28 NWS National Hurricane Center Miami FL AL092017 400 AM CDT Sun Aug 27 2017 Although the radar presentation of the inner core of Harvey has degraded considerably, the system continues to produce intense convection in bands to the east and southeast of the center. The current intensity estimate is set to 40 kt based on surface synoptic data over southeastern Texas. Since the center is expected to remain mainly over land during the forecast period, continued weakening is likely. Given that a significant portion of the circulation is over water, however, this weakening should be very slow to occur. The official intensity forecast is similar to the model consensus. Harvey has been meandering overnight and now appears to be drifting south-southwestward. The cyclone is trapped between mid-level highs to its west-northwest and east-southeast. Over the next couple of days, the flow on the southern periphery of a trough dropping over the east-central United States should cause Harvey to move slowly southeastward to eastward. Later in the forecast period, increased ridging to east of the cyclone should cause Harvey to turn northward. The official track forecast is close to the latest model consensus and brings the center to the coast and, briefly, just offshore of southeastern Texas. At this time, it is not expected that Harvey will move far enough out over the water to result in regeneration. The biggest concern with Harvey is now the rain, a lot of rain. Rainfall totals of nearly 20 inches have been reported in the Houston area. This is resulting in catastrophic flooding which, unfortunately, will continue for some time. Key Messages: 1. While Harvey's winds are decreasing, life-threatening hazards will continue from heavy rainfall over much of southeastern Texas and from storm surge along portions of the Texas coast. 2. Catastrophic and life-threatening flooding is expected across the middle and upper Texas coast from additional rainfall of 15 to 25 inches, with isolated storm totals as high as 40 inches, through Thursday. Please heed the advice of local officials 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 3. A Storm Surge Warning remains in effect for portions of the Texas coast. Life-threatening storm surge flooding will be slow to recede due to the slow motion of Harvey and a prolonged period of onshore flow. For a depiction of areas at risk, see the Storm Surge Watch/Warning Graphic at hurricanes.gov. FORECAST POSITIONS AND MAX WINDS INIT 27/0900Z 29.2N 97.7W 40 KT 45 MPH 12H 27/1800Z 29.0N 97.4W 35 KT 40 MPH...INLAND 24H 28/0600Z 28.7N 97.0W 30 KT 35 MPH...INLAND 36H 28/1800Z 28.5N 96.6W 30 KT 35 MPH...NEAR THE COAST 48H 29/0600Z 28.5N 96.1W 30 KT 35 MPH...INLAND 72H 30/0600Z 29.4N 95.6W 30 KT 35 MPH...INLAND 96H 31/0600Z 30.8N 95.5W 25 KT 30 MPH...INLAND 120H 01/0600Z 32.0N 95.0W 25 KT 30 MPH...INLAND $$ Forecaster Pasch |