Skip Navigation Links
NOAA NOAA United States Department of Commerce

Tropical Storm ETA


ZCZC MIATCDAT4 ALL
TTAA00 KNHC DDHHMM
 
Tropical Storm Eta Discussion Number  40
NWS National Hurricane Center Miami FL       AL292020
300 AM CST Tue Nov 10 2020

There hasn't been a lot of change to the cloud pattern of Eta 
overnight, with the center apparently located on the northwestern 
side of a small central dense overcast.  Scatterometer data from 
earlier indicated 35-40 kt winds, and with the typical undersampling 
from that instrument, along with consensus 45-kt estimates from 
TAFB/SAB, so Eta's initial wind speed is kept at 45 kt.  A NOAA 
Hurricane Hunter aircraft should be in the storm this morning.

Eta is forecast to be in a low-to-moderate shear environment over 
warm SSTs for the next couple of days.  Gradual strengthening is 
expected through early Thursday, with the main restrictive factor 
being nearby dry air. After that time, increasing shear and 
drier mid-level air are likely to cause Eta to weaken. The rate 
of this weakening is pretty uncertain, and a lot depends on how 
much Eta can re-intensify over the next couple of days. The new 
forecast is similar to the previous one, which is quite close to 
the consensus guidance.  

The storm has basically become stationary overnight.  Eta should 
drift to north today due to steering flow changes with a nearby 
upper-level low losing influence while ridging east of Florida 
builds southward.  A slow northward track is then anticipated for a 
couple of days over the east-central Gulf of Mexico in this flow 
pattern.  Beyond that time, model guidance is in rather poor 
agreement, ranging from a stronger system moving faster to the 
northeast due to broad troughing over the south-central United 
States, to a weaker tropical cyclone getting caught under a narrow 
ridge over the Gulf of Mexico and turning west-southwestward.  Since 
the new forecast expects Eta to be weakening, the NHC forecast will 
be west of the consensus and west of the previous track.  I have 
little confidence in the long-range track forecast due to its 
seeming dependence on the intensity, and the wide spread in the 
guidance. 
 
Key Messages:
 
1. Heavy rainfall from Eta will continue across western Cuba and 
South Florida today and tonight.  Additional flash and urban 
flooding, especially across previously inundated areas, will be 
possible in South Florida. Flash and urban flooding will also be 
possible for western Cuba.
 
2. Eta could approach the Florida Gulf Coast later this week as a
tropical storm, and possibly bring impacts from rain, wind, and
storm surge. Interests in this area should continue to monitor
the progress of Eta and updates to the forecast this week.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  10/0900Z 22.9N  85.5W   45 KT  50 MPH
 12H  10/1800Z 23.1N  85.6W   50 KT  60 MPH
 24H  11/0600Z 24.0N  85.6W   55 KT  65 MPH
 36H  11/1800Z 25.0N  85.4W   60 KT  70 MPH
 48H  12/0600Z 26.0N  85.3W   60 KT  70 MPH
 60H  12/1800Z 26.8N  85.3W   50 KT  60 MPH
 72H  13/0600Z 27.3N  85.4W   40 KT  45 MPH
 96H  14/0600Z 28.8N  86.5W   35 KT  40 MPH
120H  15/0600Z 30.0N  87.0W   30 KT  35 MPH
 
$$
Forecaster Blake
 
NNNN