Atlantic Basin Tropical Cyclones

Hurricane Ian Forecast Discussion


555 
WTNT44 KNHC 290259
TCDAT4

Hurricane Ian Discussion Number  26
NWS National Hurricane Center Miami FL       AL092022
1100 PM EDT Wed Sep 28 2022

Ian remains inland over central Florida at this time.  Although the
eye is no longer evident on satellite or radar imagery, it 
continues to have a well-organized cloud pattern, and surface 
observations show hurricane-force winds near the system's core.  
Assuming a decay rate similar to that given by the Decay-SHIPS 
model, the current intensity is set at 80 kt.  Given the lack of 
pressure observations from surface stations, the central pressure is 
estimated using a blend of standard wind/pressure relationships.

Steady weakening will occur while Ian continues to move over land. 
Although not explicitly shown by the official forecast, the cyclone 
could still be at hurricane strength when it reaches the central 
east coast of Florida or the southeast U.S. coast.  Therefore, a 
hurricane warnings and watches are in effect for that area.  The 
environment during the next 36 hours or so does not appear to be 
conducive for strengthening, with strong shear and dry air 
prevailing.  However some intensification is possible due to a 
favorable trough interaction.  The official intensity forecast is 
above the model guidance at this time.

Ian continues to move north-northeastward, or about 030/7 kt.  
Over the next couple of days, the system should move around a 
trough near the southeastern U.S. and west of a subtropical ridge 
over the southwestern Atlantic.  The official track forecast is 
shifted slightly east of the previous one and is on top of the new 
multi-model consensus.

Since the radar presentation of the center has degraded, and the 
center is no longer easily trackable, hourly Tropical Cyclone 
Updates will no longer be issued.


Key Messages:

1. Severe and life-threatening storm surge inundation of 8 to 10 
feet above ground level along with destructive waves is ongoing 
along the southwest Florida coastline from Englewood to Bonita 
Beach, including Charlotte Harbor.

2. Hurricane-force winds, especially in gusts, will continue to
spread across central Florida near the core of Ian through early
Thursday. Hurricane conditions are expected along the east-central
Florida coast overnight through early Thursday.

3. Widespread, life-threatening catastrophic flooding, with major to
record river flooding, will continue across portions of central
Florida tonight with considerable flooding in northern Florida,
southeastern Georgia and eastern South Carolina expected tomorrow
through the end of the week.

4.  There is a danger of life-threatening storm surge on Thursday
and Friday along the coasts of northeast Florida, Georgia, and South
Carolina, with hurricane conditions possible. Residents in these
areas should follow any advice given by local officials.


FORECAST POSITIONS AND MAX WINDS

INIT  29/0300Z 27.5N  81.4W   80 KT  90 MPH...INLAND
 12H  29/1200Z 28.4N  80.9W   55 KT  65 MPH...INLAND
 24H  30/0000Z 29.6N  80.3W   55 KT  65 MPH...OVER WATER
 36H  30/1200Z 31.3N  80.1W   55 KT  65 MPH
 48H  01/0000Z 33.1N  80.5W   50 KT  60 MPH...INLAND
 60H  01/1200Z 35.0N  81.2W   30 KT  35 MPH...INLAND
 72H  02/0000Z 37.0N  81.5W   20 KT  25 MPH...POST-TROP/EXTRATROP
 96H  03/0000Z...DISSIPATED

$$
Forecaster Pasch




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