Official Discussion issued by the National Hurricane Center

Teddy (AL202020) DATA RELEASED: 9/14/2020 9:00:00 PM UTC

Copy of official data

Tropical Storm Teddy Discussion Number   9
NWS National Hurricane Center Miami FL       AL202020
500 PM AST Mon Sep 14 2020

Teddy is strengthening this afternoon. Recent satellite imagery
shows a growing convective band south and west of the center and a
CDO feature developing over the estimated low-level center position.
The initial intensity is set to 45 kt based on the latest Dvorak
estimates of T3.0/45 kt from TAFB and SAB.

The environment along Teddy's forecast track features increasing 
SSTs and low shear for the next several days, and with the improved 
convective structure of the cyclone, steady strengthening is 
forecast. The NHC intensity prediction has been increased from the 
previous advisory, and shows a 25-kt increase in the next 24 hours, 
which is supported by the SHIPS model and some of the RII indices. 
Beyond that time, Teddy is forecast to reach major hurricane 
intensity in about 3 days. The new NHC forecast is near HCCA through 
the forecast period. 

Microwave and geostationary satellite fixes suggest an initial
motion of 275/12. The track forecast reasoning is similar to that of
the  previous advisory. Teddy will initially be steered westward
and then west-northwestward by a deep-layer ridge located over the
central Atlantic. As the ridge shifts eastward through the forecast
period, Teddy is forecast to turn more northwestward as it moves
around the western edge of the ridge. There is a fair amount of 
across track spread in the guidance, with the ECMWF on the right 
and the GFS and HWRF on the left. Overall the guidance envelope has 
shifted to the left since this morning. The new NHC track has 
been adjusted in that direction, and lies near or a little to the 
right of the latest consensus aids. 

FORECAST POSITIONS AND MAX WINDS

INIT  14/2100Z 13.0N  44.0W   45 KT  50 MPH
12H  15/0600Z 13.6N  45.8W   55 KT  65 MPH
24H  15/1800Z 14.5N  47.7W   70 KT  80 MPH
36H  16/0600Z 15.4N  49.3W   75 KT  85 MPH
48H  16/1800Z 16.6N  50.8W   85 KT 100 MPH
60H  17/0600Z 17.9N  52.2W   95 KT 110 MPH
72H  17/1800Z 19.3N  53.6W  100 KT 115 MPH
96H  18/1800Z 22.0N  56.0W  105 KT 120 MPH
120H  19/1800Z 24.5N  58.5W  100 KT 115 MPH

$$
Forecaster Brennan