Official Discussion issued by the National Hurricane Center

Teddy (AL202020) DATA RELEASED: 9/15/2020 3:00:00 AM UTC

Copy of official data

Tropical Storm Teddy Discussion Number  10
NWS National Hurricane Center Miami FL       AL202020
1100 PM AST Mon Sep 14 2020

Teddy is displaying some mixed signals this evening.  On one hand, 
satellite imagery shows an improving cloud pattern, with 
increasing central convection and a large curved band on the 
southern side of the circulation. The latest TAFB/SAB Dvorak 
estimates have increased to 55 kt on this basis. Scatterometer 
data, surprisingly, only shows 35-40 kt.  The initial wind speed 
remains 45 kt as a blend of that data, assuming the typical 
undersampling from ASCAT, but there is a fair bit of uncertainty in 
the current wind speed.  Teddy should have several days in a low or 
moderate shear environment over warm waters to intensify. All 
guidance responds to this forcing by showing Teddy near major 
hurricane strength in a few days, with the biggest disagreement 
being how fast it gets there.  The new forecast is similar to the 
previous one, leaning toward the NOAA corrected-consensus guidance 

Teddy is moving about the same as before, or 280/11 kt.  No 
substantial changes were made to the forecast track with the storm 
in a seemingly stable steering current provided by a deep-layer 
ridge over the central Atlantic.  Teddy should turn 
west-northwestward overnight and then northwestward on Wednesday 
through the end of the forecast while it moves on the southwestern 
flank of the ridge.  Model guidance is in excellent agreement, with 
only some minor speed differences.  The NHC track prediction is 
basically on top of the previous one and the consensus aids.


INIT  15/0300Z 13.2N  45.0W   45 KT  50 MPH
12H  15/1200Z 13.8N  46.5W   55 KT  65 MPH
24H  16/0000Z 14.8N  48.3W   70 KT  80 MPH
36H  16/1200Z 15.9N  49.8W   80 KT  90 MPH
48H  17/0000Z 17.3N  51.3W   90 KT 105 MPH
60H  17/1200Z 18.5N  52.6W   95 KT 110 MPH
72H  18/0000Z 19.9N  54.2W  105 KT 120 MPH
96H  19/0000Z 22.6N  56.9W  105 KT 120 MPH
120H  20/0000Z 25.5N  60.0W  105 KT 120 MPH

Forecaster Blake