000 AXNT20 KNHC 101803 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Thu Dec 10 2020 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 1200 UTC surface analysis and satellite imagery through 1745 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough axis passes through the coastal areas of Sierra Leone near 08N13W to 04N20W, where latest scatterometer data shows that it transitions to the ITCZ and continues to 03N30W and to 02N41W. Scattered moderate convection is within 360 nm south the trough axis between the coast of Africa and 14W and within 210 nm south of the trough axis between 15W-19W. GULF OF MEXICO... Strong upper-level subsidence aloft and very dry stable conditions are in place over the Gulf. At the surface...a 1022 mb high pressure centered is located near 25N89W, with associated high broad surface anticyclonic wind flow spanning the entire Gulf. Latest ASCAT data generally shows light to gentle anticyclonic flow over the the basin along with seas of 3 ft or less. As for the forecast: the high pressure will shift eastward through Friday. Southerly winds will increase in the western Gulf of Mexico tonight through Sat. A strong cold front will move into the NW Gulf of Mexico Sun night, and extend from central Florida to southern Mexico on Mon. Strong northerly winds are expected north of the front, with possible gale force winds along the western Gulf coast near the coast of Veracruz. CARIBBEAN SEA... A dissipating stationary front stretches from the Atlantic southwestward to the eastern part of Hispaniola and to near 15N78W. Broken to overcast multi-layered clouds, with possible scattered showers are within 250 nm to the northwest of the front including the vast majority of Hispaniola. The monsoon trough is along 08N/10N from 73W across northern Colombia and Panama. Isolated showers are south of 12N and west of 72W into the countries of Central America. Patches of low-level moisture advecting westward, with possible isolated showers are noted over the eastern and central Caribbean mainly north of 15N. As for the forecast: The front will dissipate by late this afternoon. Fresh northerly winds northwest of the front, as were evident in an 1452Z will gradually diminish into Fri morning. Fresh to strong winds will pulse overnight near the coast of Colombia through Sun. ATLANTIC OCEAN... A stationary front extends from near 32N53W to 29N56W, where it transitions to a cold front to the eastern part of Hispaniola. This cold front is being driven by a broad upper-level troughing that covers the area north of about 24N and west of the front to near 58W. The combination of low-level forcing created by the front along with upper-level dynamics from the upper-level trough is resulting in scattered showers and thunderstorms along and within 120 nm east and southeast of the front north of 25N. Scattered showers and isolated thunderstorms are along and within 90 nm east of the front from 21N-25N. The cold front will become stationary and weaken today. An upper-level low is identified to be near 19N46W, with a trough southwestward to near 13N49W and to near 06N55W. At the surface, a trough is along a position from 19N45W to 13N48W. Latest satellite imagery shows an area of scattered moderate convection from 14N to 24N between 40W-44W and also from 15N to 20N between 44W-50W. Scattered showers and isolated thunderstorms are seen elsewhere from 14N-21N between 38W-51W. The tail-end of the upper-level trough, in combination with low-level easterly moisture, is helping to trigger off scattered showers and isolated thunderstorms roughly from just inland the coast of Suriname as well as over northern French Guiana northward to 12N and between 50W-56W. The upper-level low is forecast to lift northward through Fri and become absorbed by the aforementioned broad upper- level trough late Fri night. High pressure will build eastward across the forecast area through Fri. Over the eastern section of the area, a 1033 mb high center is located north of the area near 33N27W, with a ridge extending southwestward to near 29N44W and to near 27N55W. Surface anticyclonic wind flow covers the Atlantic Ocean from 20N northward, east of the cold front. A cold front will move east of northern Florida on Mon. $$ Aguirre