Tropical Weather Discussion
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000 AXNT20 KNHC 120550 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1249 AM EST Wed Dec 12 2018 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 0530 UTC. ...SPECIAL FEATURES... Atlantic Gale Warning: A stationary front extends from 32N60W to 31N64W, where it becomes a cold front. The cold front continues to 29N68W to eastern Cuba. A reinforcing cold front extends from 32N69W to 29N74W to 28N77W. Scattered moderate convection is N of 29N and E of 67W, along and N of the initial front, with scattered showers from 27N-29N between 65W-68W. A recent scatterometer pass from 12/0100 UTC shows gale force winds N of 28N within 90 nm behind and 180 nm ahead of the reinforcing front. Seas are also 12 to 15 ft in this same area. Gale force winds are expected to persist across the northern waters near and E of the reinforcing front through early this morning before diminishing around 1200 UTC today. Elsewhere W of the initial front, N of 26N and east of 76W, fresh to strong NW to N winds will continue through this morning, while fresh to strong southerly winds ahead of the front will diminish by late this afternoon. Please read the latest High Seas Forecast under AWIPS/WMO headers HSFAT2/FZNT02 KNHC for more details. Gulf of Mexico Gale Warning: A cold front is forecast to enter the NW Gulf on Thu near 1200 UTC. The cold front will reach a position from the Mississippi Delta to Tamiahua, Mexico on Thu night, reach from the Florida Big Bend to the E Yucatan Peninsula on Fri morning and pass through the Straits of Florida Fri night. Strong to near gale force winds will develop ahead and west of the front, reaching gale force Thu night into Fri over most of the waters. Gale force winds are likely to extend to Veracruz, Mexico and adjacent waters. Please read the latest High Seas Forecast under AWIPS/WMO headers HSFAT2/FZNT02 KNHC for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Sierra Leone near 09N13W to 05N16W to 04N20W. The ITCZ continues from that point to 03N30W to 00N40W to the coast of Brazil near 00N49W. Scattered moderate convection is noted from 00N-04N between 05W-23W, and from 02N-05N between 23W-40W. Scattered showers are seen from 00N-08N between 40W and the coast of South America. GULF OF MEXICO... A weak surface trough is located in the SW Gulf from 23N97W to 19N95W. Otherwise, a 1028 mb high pressure is centered over the western Florida Panhandle and S Alabama near 31N87W with a surface ridge extending across the entire Gulf. Low-level stratus is noted in the SW Gulf of Mexico and Bay of Campeche. Fresh to locally strong southerly return flow will prevail across the western Gulf waters this morning through early Thu ahead of a cold front entering the northwest Gulf on Thu near 1200 UTC. Gale force winds are expected with this front over much of the Gulf Thu night into Fri. Mainly fresh west flow is expected on Sat with seas diminishing to less than 8 ft Sun. CARIBBEAN SEA... A stationary front extends from eastern Cuba near 21N76W to 18N81W to Honduras near 15N88W. Scattered showers are noted near and west of the frontal boundary. Water vapor imagery shows very dry air across the eastern Caribbean N of 14N and E of 69W, with more moderately dry air elsewhere over the eastern and central Caribbean. Fresh to strong trade winds will prevail in the S central Caribbean through Sun night with nocturnal pulses to near gale force off the northwest coast of Colombia. Fresh to strong winds will spread N to western Hispaniola Fri morning as high pressure N of the area strengthens. The stationary front from eastern Cuba to the Gulf of Honduras will gradually dissipate through late this morning, and fresh to strong northerly winds west of the boundary will diminish. Another cold front will enter the NW Caribbean on Fri afternoon with northerly fresh to strong winds west of the boundary. Fresh to strong N winds will increase to near gale force within 60 nm of the coast of Nicaragua on Sat night as the front stalls from eastern Cuba to northern Costa Rica. ATLANTIC OCEAN... Please see the Special Features section for information on the Gale Warning in the Atlantic associated with two cold fronts. Otherwise, a ridge of high pressure extending from a 1027 mb high pressure near 27N45W dominates the remainder of the basin E of the cold fronts. Isolated shower activity is noted mainly S of 23N across the tropics outside of heavier activity discussed in the Monsoon Trough/ITCZ section. A strong ridge will build N of the area on Thu ahead of the next cold front to come off Florida Fri evening. Strong to near gale force southerly return flow is expected north of the Bahamas beginning Thu night and continuing through Sun evening. Gale force winds are likely over the NW waters Fri night. For additional information please visit $$ Hagen is the U.S. government's official web portal to all federal, state and local government web resources and services.