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Post-Tropical Cyclone Gamma Forecast Discussion


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000
WTNT45 KNHC 060231
TCDAT5

Post-Tropical Cyclone Gamma Discussion Number  15
NWS National Hurricane Center Miami FL       AL252020
1000 PM CDT Mon Oct 05 2020

Gamma was entirely devoid of convection for most of the day. Shortly
before sunset, a few disorganized thunderstorms developed to the
southeast of the cyclone's center, however these appear to be forced
at least in part by a sea breeze boundary and are not exclusively
associated with Gamma. A few other small cells of convection have
developed to the west of Gamma's center during the past hour or so,
but not nearly enough to be considered sufficiently organized to
meet the requirement for a tropical cyclone. Gamma is therefore now
considered to be post-tropical and this will be the last NHC
advisory.

The cyclone could still produce some additional disorganized 
convection and periods of heavy rain overnight as it moves inland 
over the Yucatan peninsula, but this is not expected to result in 
significant regeneration. Some of this rain could impact areas that 
are preparing for the much more significant approach of Hurricane 
Delta in a day or so. The cyclone is moving southwestward near 
5 kt, and this should continue for another day or so until it 
dissipates. The winds associated with Gamma's remnants should 
gradually weaken through that time, though the system could still 
produce a few areas of heavy rain over southeastern Mexico.

It is worth noting that several model trackers, and consequently
the consensus aids, depict that Gamma will move northward over the
Gulf of Mexico and strengthen significantly in a couple of days.
This is because the trackers lose track of Gamma when it dissipates
and start following nearby Hurricane Delta instead. In reality, no 
models forecast that Gamma will remain a well-defined cyclone for 
more than another day or two.


FORECAST POSITIONS AND MAX WINDS

INIT  06/0300Z 21.6N  88.4W   30 KT  35 MPH...POST-TROPICAL
 12H  06/1200Z 21.1N  88.9W   30 KT  35 MPH...POST-TROP/INLAND
 24H  07/0000Z 20.2N  89.6W   25 KT  30 MPH...POST-TROP/INLAND
 36H  07/1200Z...DISSIPATED

$$
Forecaster Zelinsky