je.st
news
Hurricane MATTHEW Forecast Discussion Number 39
2016-10-07 22:47:01| National Hurricane Center (Atlantic)
Issued at 500 PM EDT FRI OCT 07 2016 000 WTNT44 KNHC 072046 TCDAT4 HURRICANE MATTHEW DISCUSSION NUMBER 39 NWS NATIONAL HURRICANE CENTER MIAMI FL AL142016 500 PM EDT FRI OCT 07 2016 Data from a NOAA Hurricane Hunter plane and satellite intensity estimates indicate that Matthew has weakened a little bit and the maximum winds are 95 kt. The hurricane is heading toward an area of increasing shear, and this should result in gradual weakening. The shear is forecast to continue during the next 5 days, so additional weakening is anticipated and Matthew is expected to be a tropical depression by the end of the forecast period. Matthew has begun to move northward at about 10 kt. In about 12 hours, the hurricane will encounter the mid-latitude westerlies, and this flow pattern should induce a northeastward and then eastward motion during the next 2 days. During that time the core of the hurricane is expected to hug the coast from Georgia through southeastern North Carolina. The confidence in this portion of the track forecast is high. After that time, the steering flow becomes very complex, and both the GFS and ECMWF models turn the cyclone southward and southwestward embedded within the flow on the west side of a mid-level trough. The NHC track follows these two models, but the confidence is portion of the forecast is low. KEY MESSAGES: 1. We have been very fortunate that Matthew's strongest winds have remained a short distance offshore of the Florida Coast thus far, but this should not be a reason to let down our guard. Only a small deviation to the left of the forecast track could bring these winds onshore. The western eyewall of Matthew, which contains hurricane-force winds, is expected to move over or very near the coast of northeastern Florida and Georgia through tonight. 2. Hurricane winds increase very rapidly with height, and occupants of high-rise buildings in the Jacksonville area are at particular risk of strong winds. Winds at the top of a 30-story building will average one Saffir-Simpson category higher than the winds near the surface. 3. The water hazards remain, even if the core of Matthew remains offshore. These include the danger of life-threatening inundation from storm surge, as well as inland flooding from heavy rains from Florida to North Carolina. 4. The National Hurricane Center is issuing Potential Storm Surge Flooding Maps, and Prototype Storm Surge Watch/Warning Graphics for Matthew. It is important to remember that the Potential Storm Surge Flooding Map does not represent a forecast of expected inundation, but rather depicts a reasonable worst-case scenario -- the amount of inundation that has a 10 percent chance of being exceeded. FORECAST POSITIONS AND MAX WINDS INIT 07/2100Z 30.2N 80.7W 95 KT 110 MPH 12H 08/0600Z 31.7N 80.7W 90 KT 105 MPH 24H 08/1800Z 33.0N 79.0W 80 KT 90 MPH 36H 09/0600Z 33.8N 76.7W 65 KT 75 MPH 48H 09/1800Z 33.5N 75.0W 60 KT 70 MPH 72H 10/1800Z 30.0N 74.5W 40 KT 45 MPH 96H 11/1800Z 27.0N 76.0W 35 KT 40 MPH 120H 12/1800Z 26.0N 77.0W 30 KT 35 MPH $$ Forecaster Avila
Tags: number
discussion
matthew
forecast
Category:Transportation and Logistics