000 AXNT20 KNHC 021048 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Fri Oct 2 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 0600 UTC surface analysis and satellite imagery through 1000 UTC. ...SPECIAL FEATURES... Low pressure in the northwest Caribbean is becoming better organized this morning. The low is centered near 17N84W, and has an estimated pressure of 1006 mb. Strong, rotating convection is building near the center of the low, and a large band is observed within 180 nm to the northeast of the center. The low pressure developed along a tropical wave, currently moving into Central America. Environmental conditions are favorable enough to support a high chance for the low pressure to develop into a tropical depression or a tropical storm today or Saturday as it moves slowly to the northwest into the northeastern Yucatan peninsula. The low may emerge into the south central Gulf of Mexico by Sunday, then shift westward through early next week. Regardless of development, the slow moving low pressure will likely bring heavy rains, with possible flash flooding, to portions of southeastern Mexico, Central America, and western Cuba during the next several days. Seas will build over the far northwestern Caribbean and Yucatan Channel through Saturday night, and in the south- central Gulf through early next week. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 36W from 16N southward, moving west at 10 to 15 knots. Scattered moderate convection is noted near the wave axis and along the ITCZ from 06N to 11N between 30W and 40W. A Caribbean Sea tropical wave is along 66W from 19N southward, moving west at 10 to 15 knots. Scattered moderate to isolated strong convection is evident from 11N to 13N between 63W and 68W. A Caribbean Sea tropical wave is along 84W south of 20N, moving west at 10 to 15 kt. Showers and thunderstorms are described in the Special Features section above. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Senegal near 12N16W to 11N20W. The ITCZ continues from 11N20W to 10N34W, and from 08N38W to 06N57W. Scattered moderate convection is noted from 06N to 11N between 30W and 40W. GULF OF MEXICO... A dissipating stationary front extends from southwest Florida to the north central part of the Yucatan peninsula. Scattered moderate convection is noted within 75 nm north of the front. A scatterometer pass from 03 UTC indicated fresh to strong NE winds over much of the south-central Gulf to the north of the front, and ahead of the developing low pressure nearby in the northwest Caribbean. Fresh to strong NW to N winds are also evident over the far southwest Gulf of Mexico, south of 20N, where a recent altimeter pass indicated seas of 6 to 8 ft. Farther north, a reinforcing cold front is moving through the norther Gulf, reaching from the Florida Big Bend area to central Texas. Buoy and platform observations indicate fresh northerly winds are following the front from the western Florida Panhandle to the north Texas coast. Elsewhere, gentle to moderate winds and 3 to 5 ft seas are noted. For the forecast, the low pressure is expected to move into the Yucatan peninsula and south central Gulf through Sat, possibly as a tropical depression, supporting strong to near-gale force winds and building seas across the south central Gulf into early next week. Meanwhile farther north, a reinforcing front over the northern Gulf will move across the northeast Gulf today, eventually stalling and dissipating across southern Florida and the southeast Gulf through Sat. CARIBBEAN SEA... Please see the Special Features section above for information on the developing low pressure in the northwest Caribbean. Elsewhere across the Caribbean, a broad mid to upper trough north of Puerto Rico is bringing dry and stable air across the Dominican Republic and the Mona Passage. Divergent flow aloft on the southeast periphery of the upper trough is enhancing the shower and thunderstorm activity over the eastern Caribbean, near the tropical wave along 66W. Fresh to strong trade winds persist over the eastern and central Caribbean, between the Bermuda high to the north and the lower pressure over the western Caribbean, and seas are generally 6 to 9 ft. Winds and seas will gradually subside across the entire Caribbean basin early next week as the low moves farther to the northwest and the ridge north of the area weakens and shifts eastward. ATLANTIC OCEAN... A stationary front passes through 32N74W, to the NW Bahamas, to 26N80W in south Florida. The front is under a sharp upper ridge extending to the northeast of the broad upper anticyclone covering the developing low in the northwest Caribbean. Convergent southeast flow into the front along with divergence along this upper ridge is supporting clusters of showers and thunderstorms along and within 120 nm of the front. Gentle to moderate winds and 3 to 5 ft seas are observed over the waters north of 22N and west of 65W. Moderate to fresh trade winds and 5 to 7 ft seas south of 22N. For the forecast west of 65W, the stationary front extending from 32N74W to southeast Florida will gradually dissipate through late today. A reinforcing cold front will move into the waters off NE Florida late today, before also stalling from near 31N79W to central Florida by Sat afternoon, and then retreating northward as a warm front on Sun. Meanwhile, the Bermuda High north of the area and lower pressure in northwest Caribbean will support moderate to fresh trades south of 22N, occasionally pulsing to strong north of Hispaniola during the overnight hours through Sun night. Looking ahead, a third weak front will move over the Atlantic waters east of NE Florida late Sun and dissipate by early Tue. Farther east, 1034 mb high pressure is centered near 41N38W. A couple of weak troughs are noted south of the high pressure, north of 22N along roughly 40W and 50W. Fresh E winds and seas to 8 ft persist near the trough along 40W, but winds and seas are expected to subside today. Generally moderate trades persist farther south into the tropics, with 5 to 7 ft seas. Fresh to strong NE winds with 6 to 9 ft seas are noted off North Africa. $$ Christensen