000
ABNT20 KNHC 170907
TWOAT 

Special Tropical Weather Outlook
NWS National Hurricane Center Miami FL
510 AM EDT Thu Sep 17 2020

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

Special Tropical Weather Outlook issued to update the discussion of 
the low pressure system over the southwestern Gulf of Mexico.

The National Hurricane Center is issuing advisories on Tropical 
Depression Sally, located inland over southeastern Alabama, on 
Hurricane Teddy, located over the central tropical Atlantic, and on 
Tropical Storm Vicky, located over the eastern tropical Atlantic. 

Thunderstorm activity has continued to increase and become better 
organized this morning in association with a well-defined low 
pressure system located over the southwestern Gulf of Mexico. 
Upper-level winds are gradually becoming more conducive for 
development and, if this recent development trend continues, 
a tropical depression or a tropical could form later today. The 
low is expected to meander over the southwestern Gulf of Mexico for 
the next day or so before moving slowly northward to 
northeastward on Friday and Saturday.  An Air Force Reserve 
reconnaissance aircraft is scheduled to investigate the disturbance 
this afternoon.
* Formation chance through 48 hours...high...90 percent. 
* Formation chance through 5 days...high...90 percent.

An elongated area of low pressure located a few hundred miles 
south-southwest of the Cabo Verde Islands is producing disorganized 
shower and thunderstorm activity.  Environmental conditions are 
expected to be conducive for development during the next few days, 
and a tropical depression could form before upper-level winds become 
less favorable over the weekend.  The low is forecast to move 
west-northwestward at 10 to 15 mph during the next several days.
* Formation chance through 48 hours...medium...40 percent. 
* Formation chance through 5 days...medium...60 percent.

A non-tropical area of low pressure is located over the far 
northeastern Atlantic Ocean a few hundred miles east-northeast of 
the Azores.  This system is forecast to move east-southeastward and 
then northeastward at about 10 mph over the next day or two, and its 
chances of acquiring some subtropical characteristics before it 
reaches the coast of Portugal late Friday appear to be decreasing.  
For more information on this system, see High Seas Forecasts issued 
by Meteo France. 
* Formation chance through 48 hours...low...10 percent. 
* Formation chance through 5 days...low...10 percent.

&&

High Seas Forecasts issued by Meteo France can be found under WMO 
header FQNT50 LFPW and available on the web at 
www.meteofrance.com/previsions-meteo-marine/bulletin/grandlarge/ 
metarea2

$$
Forecaster Stewart