000 AXNT20 KNHC 200550 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1250 AM EST Mon Nov 20 2017 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 0000 UTC surface analysis and satellite imagery through 0515 UTC. ...SPECIAL FEATURE... Strong high pressure building behind a cold front over the Gulf of Mexico is supporting gale force winds S of 21N W of the front. These winds are forecast to continue through Monday morning. Wave heights of 8 to 12 ft are expected associated with these winds. See the latest high seas forecast under AWIPS/WMO headers HSFAT2/FZNT02 for more details. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 10N14W to 07N21W. The Intertropical Convergence Zone axis extends from 07N21W to 05N36W to the South American coast near 07N58W. Clusters of scattered moderate convection are from 02N-09N between 20W-31W, and from 06N-10N between 31W-48W. ...DISCUSSION... GULF OF MEXICO... As of 0300 UTC, a cold front extends from S Florida near 26N82W to 22N93W to the Bay of Campeche near 19N96W. A gale is over the SW Gulf S of 21N W of the front. See above. This front is void of precipitation. Elsewhere, radar imagery shows isolated showers are over the SE Gulf from 24N-25N between 82W-84W. In the upper levels, zonal flow is noted. Strong subsidence is over the Gulf except along the Texas and Louisiana coasts. Expect over the next 24 hours for the front to stall from S Florida to the SW Bay of Campeche, and then begin to slowly retrograde back N. CARIBBEAN SEA... A 1008 mb low is centered over the central Caribbean near 15N72W. A surface trough extends NE from the low through the Mona Passage to the Atlantic near 22N66W. Scattered moderate to isolated strong convection is near the low from 12N-18N between 68W-71W, to include Aruba and Curacao. Scattered showers are elsewhere within 180 nm of the trough axis, to include Puerto Rico and the Virgin Islands. In the upper levels, an upper level trough is over the NW Caribbean with axis from E Cuba near 20N74W to the Gulf of Honduras near 16N89W. Upper level diffluence E of the trough is enhancing the showers and convection over the central Caribbean Sea. Expect the area of convection to drift W and persist for the next 24 hours. ...HISPANIOLA... Scattered showers are over Hispaniola, and will continue through Tuesday. Expect convection to build over Hispaniola in the afternoon and evening hours during maximum heating. Localized flooding is also possible during this time. ATLANTIC OCEAN... As of 0300 UTC, a cold front is over the W Atlantic from 31N74W to near West Palm Beach Florida. Scattered showers are within 60 nm of the front. A 1020 mb high is centered over the central Atlantic near 34N53W producing fair weather. A 1008 mb low is centered over the E Atlantic near 31N34W. A cold front extends SW from the low to 27N40W to 22N54W. Isolated moderate convection is within 120 nm of the front. A surface trough is just e of the Canary Islands from 30N11W to 25N16W. Scattered showers are over the Canary Islands. Of note in the upper levels, an upper level trough is over the W Atlantic enhancing the W Atlantic front. Another upper level trough is over the central Atlantic with axis from 31N46W to 23N53W. Upper level diffluence is E of this trough. In addition a small upper level low is centered near the Canary Islands at 30N13W. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa