Official Discussion issued by the National Hurricane Center

Gamma (AL252020) DATA RELEASED: 10/3/2020 10:00:00 AM UTC

Copy of official data

Tropical Storm Gamma Discussion Number   5
NWS National Hurricane Center Miami FL       AL252020
1000 AM CDT Sat Oct 03 2020

Observations from both the Air Force and NOAA Hurricane Hunters 
indicate that Gamma has continued to strengthen this morning.  The 
cloud pattern has continued to become better organized, with an eye 
trying to become evident on high-resolution satellite images from 
the GOES-16 mesoscale sectors.  Flight-level and SFMR-observed 
surface winds from the aircraft support an intensity of 60 kt, and 
the storm could strengthen a little more as long as the center 
remains over water.  Since Gamma will be near or at hurricane 
intensity when it makes landfall later today, the government of 
Mexico has issued a Hurricane Warning for a portion of the 
northeastern Yucatan Peninsula.  Gamma should weaken some while it 
moves over land tonight.  Some re-intensification is likely after 
the center moves into the southern Gulf of Mexico.  However, the 
numerical guidance does not show much strengthening during the next 
few days, possibly due to the influence of drier air and/or the 
interaction with another area of low pressure to the east of Gamma. 
The official intensity forecast is near or above the model 

Gamma continues northwestward at near 8 kt.  The cyclone is 
expected to turn north-northwestward and move through a break in 
the subtropical ridge through 36 hours or so.  Thereafter, a trough 
to the north moves eastward, bypassing Gamma, and later in the 
forecast period a ridge builds weakly over the Gulf of Mexico.  
This should cause the cyclone to turn toward the west and 
southwest.  The official track forecast is close to the multi-model 
consensus, TVCN.

Although Gamma has strengthened, its biggest threat continues to be 
torrential rains, flooding, and mudslides especially near and over 
mountainous terrain.


1. Gamma is expected to produce heavy rainfall for several 
days over portions of southeastern Mexico, the Yucatan 
Peninsula, Central America, and far western Cuba.  This 
rainfall could result in life-threatening flash flooding 
and mudslides, particularly in the mountainous regions of 
southeastern Mexico and Central America.

2. Gamma is very near hurricane strength and will be near or at 
hurricane intensity when the center moves inland over the Yucatan
Peninsula later today.  A Hurricane Warning is now in effect
for portions of the east coast of the Yucatan Peninsula, where
tropical storm conditions are already occurring.  Tropical storm 
conditions are expected along the north coast of the Yucatan 
Peninsula within the Tropical Storm Warning area later today 
and on Sunday.


INIT  03/1500Z 20.0N  87.3W   60 KT  70 MPH
12H  04/0000Z 20.8N  87.8W   55 KT  65 MPH...INLAND
24H  04/1200Z 21.8N  88.1W   40 KT  45 MPH...OVER WATER
36H  05/0000Z 22.2N  88.3W   40 KT  45 MPH
48H  05/1200Z 22.3N  88.8W   45 KT  50 MPH
60H  06/0000Z 22.1N  89.7W   50 KT  60 MPH
72H  06/1200Z 22.0N  91.0W   50 KT  60 MPH
96H  07/1200Z 21.0N  92.5W   45 KT  50 MPH
120H  08/1200Z 20.0N  93.5W   40 KT  45 MPH

Forecaster Pasch