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Tropical Storm THETA

Tropical Storm Theta Discussion Number  21
NWS National Hurricane Center Miami FL       AL302020
300 AM GMT Sun Nov 15 2020
Theta remains a highly sheared but resilient tropical cyclone with
little change in its satellite appearance since the previous
advisory. A persistent band of deep convection to the southeast of
Theta remains within about 60 n mi of the storm center, despite a
hostile environment characterized by dry mid-level air and 40-50 kt
of northerly shear. Unfortunately, several scatterometer passes this
evening missed the core of the cyclone. Since the satellite
presentation is generally unchanged from earlier today, the initial
intensity is held at 35 kt, which is consistent with a T2.5 Dvorak
classification received from TAFB.
Strong northerly shear and continued dry air entrainment will 
eventually take a toll on Theta, but recent satellite trends and the 
latest GFS simulated satellite imagery suggest that the cyclone 
could remain tropical a little longer than previously forecast. The 
latest NHC intensity forecast keeps Theta as a 35-kt tropical storm 
at 12 h before weakening it into a remnant low by 24 h. This follows 
the consensus of the latest intensity guidance. Thereafter, 
continued weakening is expected through its dissipation early next 
Theta is still moving eastward at around 4 kt. The cyclone should 
begin turning northeastward later today, and then accelerate 
north-northeastward on Monday as the shallow remnant low is steered 
by a low-level ridge centered over northwestern Africa. The remains 
of Theta are forecast to open up into a trough and dissipate by 60 h 
ahead of an approaching cold front over the northeastern Atlantic. 
The latest NHC track forecast is adjusted slightly to the left of 
the previous one, which generally follows the latest track consensus 
aids. On the forecast track, the remnant low of Theta is expected to 
pass near the island of Madeira late Sunday night or early Monday.
INIT  15/0300Z 31.7N  18.7W   35 KT  40 MPH
 12H  15/1200Z 31.9N  18.0W   35 KT  40 MPH
 24H  16/0000Z 32.6N  17.4W   30 KT  35 MPH...POST-TROP/REMNT LOW
 36H  16/1200Z 34.2N  17.1W   25 KT  30 MPH...POST-TROP/REMNT LOW
 48H  17/0000Z 36.7N  15.9W   20 KT  25 MPH...POST-TROP/REMNT LOW
 60H  17/1200Z...DISSIPATED
Forecaster Reinhart/Cangialosi