Official Discussion issued by the National Hurricane Center

Hermine (AL102022) DATA RELEASED: 9/24/2022 2:00:00 AM UTC

Copy of official data

Tropical Storm Hermine Discussion Number   3
NWS National Hurricane Center Miami FL       AL102022
200 AM CVT Sat Sep 24 2022

Hermine has changed little in organization since earlier this 
evening. Persistent deep convection has been occurring in the 
northeastern quadrant, with the estimated low-level circulation 
center located just to the southwest of the edge of the convection. 
The initial intensity remains 35 kt based on the latest Dvorak 
intensity estimate from TAFB.

The cyclone has turned northward and is moving at a heading of 350/9 
kt toward a break in the eastern Atlantic subtropical ridge. A 
northward to northeastward motion is expected into early next week 
while Hermine remains in tact. A turn to the northwest is expected 
by 72 h as the cyclone becomes shallow and steered by the low-level 
flow. The latest NHC track forecast is near the previous one through 
60 h, but is a little to the right thereafter due to an overall 
shift in the track guidance. 

Hermine now has about 18-24 hours to intensify in the presence of 
marginal SSTs and moderate southwesterly vertical wind shear. After 
24 h, the southwesterly shear is forecast to progressively increase 
while dry air gets pulled into the storm's environment. Therefore 
weakening is expected after that time, and both the ECMWF and GFS 
simulated satellite imagery suggests that Hermine should degenerate 
into a remnant low devoid of deep convection on Monday. The latest 
NHC intensity forecast is unchanged from the previous one, and is on 
the high end of the guidance.

Hermine is expected to produce 2 to 4 inches of rain, with isolated 
totals of 6 inches, over the Canary Islands through this weekend due 
to a combination of a mid-latitude trough and moisture from the 
cyclone. This rainfall could cause some flash flooding in areas of 
higher terrain.


FORECAST POSITIONS AND MAX WINDS

INIT  24/0300Z 19.4N  20.8W   35 KT  40 MPH
12H  24/1200Z 20.7N  21.0W   40 KT  45 MPH
24H  25/0000Z 22.3N  21.1W   35 KT  40 MPH
36H  25/1200Z 23.8N  20.8W   30 KT  35 MPH
48H  26/0000Z 24.7N  20.4W   30 KT  35 MPH
60H  26/1200Z 25.4N  20.3W   25 KT  30 MPH...POST-TROP/REMNT LOW
72H  27/0000Z 26.1N  21.7W   25 KT  30 MPH...POST-TROP/REMNT LOW
96H  28/0000Z 27.8N  25.3W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  29/0000Z...DISSIPATED

$$
Forecaster Latto