| Hurricane Maria Discussion Number 36 NWS National Hurricane Center Miami FL AL152017 1100 PM EDT Sun Sep 24 2017 Hurricane Hunter observations indicate that Maria has weakened. Using a blend of flight-level winds and SFMR-observed surface winds along with a dropsonde in the northeast eyewall of the hurricane, the current intensity is set at 80 kt. Observations from a NOAA aircraft indicate that the SSTs beneath Maria are on the order of 24-25 deg C, which has probably contributed to the decrease of intensity. These relatively cool waters are likely due to mixing and upwelling from slow-moving Hurricane Jose, which traversed the area a little over a week ago. Gradual weakening is anticipated for the next few days, and the official intensity forecast is near or above the latest model consensus. Maria is expected to remain a hurricane for at least the next few days, however. Based on a number of center fixes from the Air Force and NOAA Hurricane Hunters, the motion is northward at a slightly slower speed, or 360/7 kt. Maria is being steered by the flow between a mid-level cyclone near the southeastern U.S. and a subtropical ridge over the southwestern Atlantic. A mid-level ridge over the northeastern U.S. will likely cause Maria's forward motion to slow some more over the next couple of days. The global models predict that this ridge will break down by 72 hours, and this should allow Maria to turn to the right as it begins to approach the mid-latitude westerlies. The official track forecast is similar to the previous one and lies near the left edge of the numerical guidance, in deference to the reliable ECMWF which is the westernmost of the model tracks. Maria is a large hurricane, so it could bring tropical storm conditions to portions of the North Carolina coast in a couple of days, even if its center remains well offshore. KEY MESSAGES: 1. Maria is forecast to continue moving northward, paralleling the U.S. east coast, and it is likely that some direct impacts will occur along portions of the coast beginning Tuesday, and a Tropical Storm Watch has been issued for a portion of the coast of North Carolina. 2. Storm surge flooding especially along the sound side of the North Carolina Outer Banks is possible beginning Tuesday, and a Storm Surge Watch has been issued for a portion of the North Carolina Outer Banks. 3. Swells from Maria are increasing along the coast of the southeastern United States and are expected to reach the Mid- Atlantic coast tonight or on Monday. These swells will likely cause dangerous surf and rip currents at beaches in these areas through much of the week. For more information, please monitor information from your local National Weather Service office at www.weather.gov. FORECAST POSITIONS AND MAX WINDS INIT 25/0300Z 30.0N 73.0W 80 KT 90 MPH 12H 25/1200Z 30.8N 73.2W 80 KT 90 MPH 24H 26/0000Z 31.9N 73.3W 75 KT 85 MPH 36H 26/1200Z 33.0N 73.5W 75 KT 85 MPH 48H 27/0000Z 33.9N 73.5W 70 KT 80 MPH 72H 28/0000Z 35.2N 72.8W 65 KT 75 MPH 96H 29/0000Z 36.5N 69.5W 65 KT 75 MPH 120H 30/0000Z 38.0N 62.0W 65 KT 75 MPH $$ Forecaster Pasch |