Atlantic Hurricane Feed

Post-Tropical Cyclone Ian Forecast Discussion



000
WTNT44 KNHC 010252
TCDAT4

Post-Tropical Cyclone Ian Discussion Number  34
NWS National Hurricane Center Miami FL       AL092022
1100 PM EDT Fri Sep 30 2022

Ian has a classic comma-shaped cloud pattern of an extratropical 
cyclone in satellite imagery. The radar structure of the system has 
degraded tonight, but surface observations indicate the center of 
Ian is moving northward across the central portion of North 
Carolina. The initial intensity is lowered to 45 kt for this 
advisory, which is consistent with the latest Decay-SHIPS guidance 
and some marine observations offshore of the Cape Fear region that 
indicate sustained tropical-storm-force winds are still occurring 
over water.

Ian is still moving northward at about 13 kt. This general motion is 
expected to continue through Saturday, which will bring Ian across 
the central portions of North Carolina and Virginia on Saturday. 
Continued weakening is forecast, and the cyclone is expected to 
dissipate by early Sunday. There were no notable changes made to the 
NHC track or intensity forecast.

Because recent observations indicate that wind speeds over land have 
diminished, the Tropical Storm Warning has been discontinued for the 
coasts of South Carolina and North Carolina. Similarly, coastal 
water levels have receded below warning criteria along the coast of 
North Carolina, and the Storm Surge Watches and Warnings there have 
also been discontinued. However, heavy rain and gusty winds are 
expected to continue into tomorrow morning across portions of the 
Carolinas and Mid-Atlantic states.

Even though all tropical watches and warnings have been 
discontinued, intermediate advisories will still be issued as long 
as Ian continues to produce winds of tropical storm strength.


Key Messages:

1. Gusty winds are expected through early Saturday over portions of 
South Carolina and North Carolina.

2. Ongoing major to record river flooding will continue through next 
week across portions of central Florida. Considerable flooding is 
possible across portions of the Carolinas and southeast Virginia.  
Locally considerable flooding is possible across portions of 
northwest North Carolina and southern Virginia tonight into early 
Saturday.


FORECAST POSITIONS AND MAX WINDS

INIT  01/0300Z 35.3N  79.5W   45 KT  50 MPH...POST-TROP/EXTRATROP
 12H  01/1200Z 36.6N  79.6W   30 KT  35 MPH...POST-TROP/EXTRATROP
 24H  02/0000Z 38.0N  79.2W   20 KT  25 MPH...POST-TROP/EXTRATROP
 36H  02/1200Z...DISSIPATED

$$
Forecaster Reinhart



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