ZCZC MIATCDAT4 ALL
TTAA00 KNHC DDHHMM
 
Tropical Depression Eta Discussion Number  19
NWS National Hurricane Center Miami FL       AL292020
300 AM CST Thu Nov 05 2020

Eta has become very disorganized due to its interaction with the 
land mass of Central America, and may no longer have a surface 
circulation.  Based on a few surface observations, the maximum winds 
are estimated to be around 25 kt over the water to the north of 
Honduras.  Eta is likely to degenerate into a post-tropical low very 
soon, if it hasn't done so already.  Since the low is predicted to 
move into the northwestern Caribbean Sea by tomorrow night, some 
restrengthening is forecast to begin by the weekend.  However the 
expected broad nature of the cyclone and stronger vertical shear are 
likely to limit strengthening over the next several days.  The 
official intensity forecast is similar to the latest model 
consensus.

The center is extremely difficult to locate at this time, but based 
on continuity the initial motion is estimated to be 300/7 kt.  Eta, 
or its post-tropical remnant low/trough, should continue to move 
over land today, and then turn northward tonight while moving along 
the eastern side of a broader gyre.  This will take the system into 
the Gulf of Honduras and over the northwestern Caribbean Sea on 
Friday.  A negatively-tilted 500-mb trough/low developing over the 
Gulf of Mexico should induce a generally northeastward motion for 
the next 2-3 days and take the cyclone across portions of Cuba in 
3-4 days.  Thereafter, the system is forecast to rotate cyclonically 
around the eastern side of the 500 mb low and turn northwestward to 
westward by the end of the forecast period.  The official forecast 
is a blend of the latest GFS and ECMWF predictions, but leans toward 
the latter model.  This track could take the system near or over 
portions of extreme southern Florida by late this weekend or early 
next week, but there is low confidence in the forecast, especially 
at 3-5 days. 


Key Messages:
 
1. Through Monday morning, heavy rainfall from Eta will lead to
catastrophic, life-threatening flash flooding and river flooding
across portions of Central America, along with landslides in areas
of higher terrain.  Flash and river flooding is also possible across
Jamaica, southeast Mexico, the Cayman Islands and western Cuba.
 
2. Eta is forecast to regain tropical storm strength over the
northwestern Caribbean Sea late this week. Although the details of
the future track and intensity of Eta are uncertain, there is an
increasing risk of impacts from wind and rainfall in portions of
Cuba, southern Florida and the Florida Keys this weekend and early
next week.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  05/0900Z 14.5N  87.0W   25 KT  30 MPH
 12H  05/1800Z 15.0N  87.8W   25 KT  30 MPH...POST-TROP/REMNT LOW
 24H  06/0600Z 16.2N  87.8W   30 KT  35 MPH...POST-TROP/REMNT LOW
 36H  06/1800Z 17.4N  86.3W   35 KT  40 MPH...TROPICAL CYCLONE
 48H  07/0600Z 18.5N  84.7W   40 KT  45 MPH
 60H  07/1800Z 19.6N  82.9W   45 KT  50 MPH
 72H  08/0600Z 21.0N  81.0W   50 KT  60 MPH
 96H  09/0600Z 23.5N  79.5W   50 KT  60 MPH
120H  10/0600Z 24.5N  81.5W   55 KT  65 MPH
 
$$
Forecaster Pasch
 
NNNN