Official Discussion issued by the National Hurricane Center

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

Copy of official data

Tropical Storm Teddy Discussion Number  13
NWS National Hurricane Center Miami FL       AL202020
500 PM AST Tue Sep 15 2020

Overall, Teddy's organization has continued to slowly improve 
during the past several hours. AMSR microwave imagery near 1630 UTC 
showed that a low- to mid-level eye feature is beginning to form. 
The overall convective pattern has also improved, though not enough 
to increase the intensity estimates at this time, which only range 
from 45-55 kt. The intensity is therefore held at 55 kt, but it 
does appear that some intensification is imminent.

The AMSR image showed indications of a microwave signature commonly 
associated with rapid intensification in favorable environments. Low 
shear and warm SSTs along the forecast track are certainly 
conducive, though dry air continues to be a possible limiting 
factor. The dry air is probably the reason that dry slots continue 
to occasionally appear in IR imagery near the center of Teddy. Rapid 
intensification probabilities are not particularly high; the SHIPS 
RI gives a 22 percent chance of a 30-kt increase during the next 24 
h while DTOPS shows a mere 1 percent chance. The rest of the 
intensity models forecast only modest strengthening for the next 
couple of days. The NHC intensity forecast is at the top of the 
intensity guidance for the next 48 h and slightly above all of the 
models after that, but I am hesitant to lower it any further at 
this time given the recent microwave signature and overall 
improvement in Teddy's structure.

In contrast, Teddy's track outlook remains straightforward, and no 
changes of note were made to the official forecast. The tropical 
storm is turning gradually toward the northwest and should begin 
moving in that direction tonight. A ridge over the central Atlantic 
should then steer Teddy in that general direction for the rest of 
the week. The model spread is still much lower than normal, and 
confidence in the track forecast is fairly high.

FORECAST POSITIONS AND MAX WINDS

INIT  15/2100Z 14.6N  47.9W   55 KT  65 MPH
12H  16/0600Z 15.5N  49.0W   65 KT  75 MPH
24H  16/1800Z 16.8N  50.2W   75 KT  85 MPH
36H  17/0600Z 18.2N  51.6W   85 KT 100 MPH
48H  17/1800Z 19.7N  53.1W   95 KT 110 MPH
60H  18/0600Z 21.0N  54.4W  100 KT 115 MPH
72H  18/1800Z 22.5N  55.8W  100 KT 115 MPH
96H  19/1800Z 25.4N  58.8W  105 KT 120 MPH
120H  20/1800Z 28.5N  61.5W   95 KT 110 MPH

$$
Forecaster Zelinsky