000 AXNT20 KNHC 122313 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Tue Jan 12 2021 Tropical Weather Discussion for North America, Central America Gulf of Mexico, Caribbean Sea, northern sections of South America, and Atlantic Ocean to the African coast from the Equator to 32N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 1800 UTC surface analysis and satellite imagery through 2300 UTC. ...SPECIAL FEATURES... Caribbean Sea Gale Warning: The pressure gradient between high pressure north of the area and the Colombian/Panamanian low is supporting strong winds across the south-central Caribbean. Latest scatterometer data provided observations of gale force winds offshore Colombia. Winds will return to gale force tonight, and then diminish to strong speeds early Wed, as well as Thu through Sat as the high pressure weakens and shifts east. Wave heights up to 12-13 ft are expected with the strongest winds. Please read the latest High Seas Forecast issued by the National Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for details. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic Ocean along the coast of Sierra Leone near 08N13W and continues southwest to near 04N20W. The ITCZ axis extends from 04N20W to 04N34W to near the Brazil and French Guiana border at 04N52W. Convection is limited, with only small area of moderate convection from 04N-05N between 28W- 30W, and also near 03N43W. Scattered moderate to isolated strong convection is observed over parts of French Guiana and Suriname. GULF OF MEXICO... A cold front extends from near Naples, Florida to Merida, Mexico in the northwest part of the Yucatan Peninsula. Doppler Radar indicates band of scattered showers across South Florida and the Straits of Florida ahead of the front. Fresh northerly winds are noted in the wake of the front, particularly between 87W-91W. The front will stall over southern Florida or the Straits of Florida on Wed, keeping the region cloudy with the risk of light rain. The front will dissipate over this area on Thu. A coastal trough is analyzed over the SW Gulf. This system will maintain strong to near gale force northwest winds within about 60-75 nm of the coast of Mexico on Wed. By Wed night into Thu, high pressure will dominate most of the Gulf waters. As a result, winds and seas will diminish. The next cold front will move into the northwest Gulf Thu night, followed by fresh to strong winds and building seas. The front is forecast to exit the Gulf on Sat. Once again, high pressure will dominate the basin on Sat. Southerly return flow will set-up across the NW Gulf by Sat night ahead of another cold front expected to move off the Texas coast late Sun. A low pressure may develop along the frontal boundary over the western Gulf by Sun night. CARIBBEAN SEA... A Gale Warning is in effect near the coast of Colombia. Please see the Special Features section for more information. Elsewhere, the latest ASCAT data passes reveal fresh to strong trade winds over the central Caribbean, and moderate to fresh winds in the remainder of the area. Convection continues to flare-up over the SW Caribbean off the coasts of Panama, Costa Rica, and extreme southeast Nicaragua. A diffluent pattern aloft supports this convective activity. Elsewhere, shallow moisture embedded in the trade wind flow will continue to move across the region producing isolated to scattered passing showers. High pressure north of the area will maintain fresh to strong trade winds across the eastern and central Caribbean through Wed night, with winds reaching gale force off Colombia overnight tonight into the early morning hours on Wed. Winds over the central Caribbean will diminish and seas will subside Thu through Sun as the high pressure weakens and shifts eastward. ATLANTIC OCEAN... From West to East, a cold front enters the forecast waters near 31N78W and continues SW to near Melbourne, FL. Abundant cloudiness with embedded showers are noted on either side of the frontal boundary, covering most of the area N of the central Bahamas and W of 70W. Fresh to strong southwest winds were observed by morning scatterometer data ahead of the cold front mainly north of 30N. As previously mentioned, the front will stall over southern Florida or the Straits of Florida on Wed, and dissipate on Thu ahead of a reinforcing cold front moving across the waters north of 27N and W of 65W. Winds and seas will increase north of the Bahamas late Fri ahead of a stronger cold front expected to move off the northeast Florida coast Sat. This front is forecast to reach from near 31N73W to the central Bahamas and to central Cuba by late Sat, and from 27N65W to the Windward Passage by late Sun. A stationary front is over the central Atlantic, and extends from 31N36W to 23N65W. This front will continue to weaken on Wed. The remainder of the Atlantic is under the influence of a ridge, anchored by a 1031 mb high pressure located N of the Madeira Islands. Fresh to strong trade winds are noted based on latest scatterometer data N of the monsoon trough/ITCZ to about to 22N-23N and E of 40W to the coast of west Africa. These winds will persist on Wed as a relatively tight pressure gradient remains over the eastern Atlantic. $$ GR