000
ABNT20 KNHC 171152
TWOAT 

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Fri Sep 17 2021

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

The Weather Prediction Center is issuing advisories on 
Post-Tropical Cyclone Nicholas, located over Louisiana. 

Showers and thunderstorms remain disorganized in association with a 
tropical wave and broad area of low pressure located about midway 
between the Lesser Antilles and the Cabo Verde Islands.  However, 
environmental conditions are expected to be conducive for 
development during the next few days, and a tropical depression 
is still likely to form over the weekend or early next week while 
moving toward the west-northwest at 15 to 20 mph across the central 
tropical Atlantic and then near or north of the Leeward Islands by 
Monday and Tuesday.  Interests in the Leeward Islands should 
monitor the progress of this system during the next few days.
* Formation chance through 48 hours...medium...60 percent.
* Formation chance through 5 days...high...70 percent.

The circulation associated with an area of low pressure located 
about 150 miles east of Cape Hatteras, North Carolina, remains 
broad and elongated, and most of the associated shower and 
thunderstorm activity is displaced well to the north and east of 
the center.  However, this system is still likely to become a 
short-lived tropical depression or tropical storm before it makes a 
transition to a non-tropical gale-force low by Saturday or Saturday 
night while moving northeastward at about 15 mph away from the 
United States mid-Atlantic and Northeast coasts.  Regardless of 
development, this system could bring high surf to portions of the 
mid-Atlantic and Northeast U.S. coasts and Atlantic Canada through 
this weekend.  Additional information on this system, including gale 
warnings, can be found in High Seas Forecasts issued by the NOAA 
Ocean Prediction Center. 
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 5 days...high...70 percent.

Disorganized cloudiness and thunderstorms over the far eastern 
tropical Atlantic are associated with a tropical wave located a 
couple of hundred miles southeast of the Cabo Verde Islands.  
Environmental conditions are forecast to be only marginally 
conducive, and development, if any, of this system should be slow to 
occur over the next few days while the system moves toward the
west-northwest or northwest at 5 to 10 mph over the far eastern 
Atlantic.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...low...20 percent.

&&
Public advisories issued by the Weather Prediction Center on 
Post-Tropical Cyclone Nicholas can be found under AWIPS header 
TCPAT4, WMO header WTNT34 KWNH, and on the web at 
https://www.wpc.ncep.noaa.gov or hurricanes.gov

High Seas Forecasts for the system off the Outer Banks of North 
Carolina issued by the NOAA Ocean Prediction Center can be found 
under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and online at 
ocean.weather.gov/shtml/NFDHSFAT1.php

$$
Forecaster Berg