000 AXNT20 KNHC 190523 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1223 AM EST Tue Dec 19 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 FEATURES... ...Gale Warning in the Caribbean Sea... Pulsing nocturnal easterly winds to gale-force are expected again near the coast of Colombia during the overnight tonight and early morning hours on Tuesday, particularly from 10N to 13N between 74W and 78W. Expect sea heights to range from 10 to 14 ft. Wind will diminish below gale-force by Tuesday afternoon, and are expected to reach again minimal gale-force at night. Thereafter, strong to near-gale force winds will persist in the area each night this week. Please read the latest NHC High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...ITCZ/MONSOON TROUGH... The monsoon trough enters the Atlantic Ocean near 07N12W and continues to 05N20W. The ITCZ extends from 05N20W to northeast Brazil near 02N50W. Scattered moderate convection is noted within about 30 nm on either side of these boundaries between 13W-27W. ...DISCUSSION... ...GULF OF MEXICO... A stationary front extends across the northern portion of the basin from 29N91W to 27N97W. A surface trough extends from that point to 20N95W. Isolated showers are noted along these boundaries. Surface ridging prevails elsewhere, anchored by a 1025 mb high centered over northwest Florida near 29N83W. The ridge is forecast to persist through Tuesday night. A weak cold front will reach the coast of Texas Wednesday, and stall across the northern Gulf by Thursday before moving north as a warm front on Thursday night. A stronger cold front will reach the northwest Gulf on Friday. Fresh southerly return flow is expected across the western Gulf ahead of the front. ...CARIBBEAN SEA... Please refer to the Special Features section for details about the gale warning near the coast of Colombia during the next two nights. The most recent scatterometer data indicated fresh to strong winds prevail over the central Caribbean and across the Windward Passage. Moderate to fresh winds prevail elsewhere. An altimeter pass indicated seas of 11 ft over the SW Caribbean in association with the strong trades. Patches of low-level moisture embedded in the trade wind flow are observed on visible satellite imagery, more concentrated over the central Caribbean. Broad mid- level anticyclonic wind flow and strong subsidence dominates the entire Caribbean Sea with fair weather. Little change is expected during the next 24-48 hours. ...HISPANIOLA... A broad mid to upper-level high is covering the Caribbean Sea and very dry air aloft supporting mostly stable conditions across the island. However, shallow moisture embedded in the trade wind flow will move across Hispaniola to produce isolated to scattered passing showers through the next 24 hours. ...ATLANTIC OCEAN... A deep layer trough in the central Atlantic is supporting a cold front that extends from 31N40W to 21N62W. The front weakens from that point to 20N67W. Mainly low-level clouds with isolated to scattered showers are along the frontal boundary. Strong high pressure building west of the front will prevail over the west Atlantic through mid-week. This pattern will keep South Florida mostly dry and warm through the weekend. East of the front, the Azores high extends across the eastern Atlantic. For additional information please visit http://www.hurricanes.gov/marine $$ ERA