000
WTNT45 KNHC 241436
TCDAT5
 
Tropical Storm Hermine Discussion Number   5
NWS National Hurricane Center Miami FL       AL102022
200 PM CVT Sat Sep 24 2022
 
Hermine is a strongly sheared and weak tropical cyclone.  Satellite
images indicate that the low-level center is exposed well to the
south-southwest of the main area of deep convection.  A recent
ASCAT-B pass caught the eastern half of the storm and showed
peak winds of about 30 kt well northeast of the center.  Based on
this data and the Dvorak estimates, Hermine is being held at a
35-kt tropical storm for this advisory, but that could be a little
generous.  Regardless, the main impact is heavy rain that continues 
across the Canary Islands.
 
The storm is moving northward at 7 kt and that motion is expected 
to continue during the next day or two while Hermine moves in the 
flow on the west side of a subtropical ridge.   After that time, a 
turn toward the left is expected as the shallow system is steered by 
the low-level flow.  The NHC track forecast remains near the middle 
of the guidance envelope.
 
Hermine is currently experiencing about 20 kt of southwesterly
vertical wind shear.  Since the shear is expected to increase while
Hermine moves into a region of cooler SSTs and drier air, weakening
is forecast.  Hermine is now predicted to become a remnant low in
36 hours, but given recent trends and the expected environment, the
transition to a post-tropical cyclone could occur sooner than that.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  24/1500Z 20.8N  20.8W   35 KT  40 MPH
 12H  25/0000Z 22.1N  20.8W   30 KT  35 MPH
 24H  25/1200Z 23.6N  20.5W   30 KT  35 MPH
 36H  26/0000Z 24.5N  20.2W   25 KT  30 MPH...POST-TROP/REMNT LOW
 48H  26/1200Z 25.0N  20.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
 60H  27/0000Z 25.4N  21.6W   25 KT  30 MPH...POST-TROP/REMNT LOW
 72H  27/1200Z...DISSIPATED
 
$$
Forecaster Cangialosi