000 AXNT20 KNHC 311035 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Sat Oct 31 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 1030 UTC. ...SPECIAL FEATURES... A developing low pressure area along a tropical wave is centered near 15N69W with an estimated MSLP of 1007 mb. The low and wave are moving westward at 15 kt. Numerous scattered to strong convection is evident near the low, from 13N to 18N between 68W and 72W. This system is slowly becoming better organized, and conditions appear conducive for further development. A tropical depression is likely to form this weekend as the system moves westward across the central and western Caribbean Sea. Regardless of development, this system is expected to produce heavy rainfall across portions of the ABC islands and Jamaica this weekend. The chance of tropical cyclone formation during the next 48 hours is high. Please refer to the website: www.nhc.noaa.gov/cyclones for more details. Potential Heavy Rainfall event: Heavy rainfall is possible across parts of Central America, from late this weekend into early next week, particularly in western Panama, Costa Rica, Nicaragua and Honduras. Flash flooding and mudslides may be possible, if heavy rainfall occurs. The rainfall threat may be enhanced by possible tropical cyclone development of the low pressure area associated with a tropical wave along 69W. Please refer to bulletins and forecasts provided by your national meteorological service for more details. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 29W from 11N southward, moving westward at 15 kt. Scattered moderate convection associated with the ITCZ is within 120 nm of the wave axis. A Caribbean Sea tropical wave is along 69W from 22N southward, moving westward at 15 kt. A low is analyzed along the wave axis near 15N69W. Please see the Special Features section above for more details on this wave and low. A Caribbean Sea tropical wave is along 73W from 21N southward, moving westward at 10 to 15 kt. Scattered moderate convection is noted from 12N to 17N between 72W and 75W. Model guidance shows this wave is likely to merge in the central Caribbean Sea with the tropical wave currently along 69W, during the next 24 hours. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains of Sierra Leone near 09N13W, to 08N16W. The ITCZ continues from 08N16W to 04N30W, to 03N46W. Scattered moderate isolated strong convection is noted from 02N to 08N between 09W and 41W. GULF OF MEXICO... A weakening cold front is slowly exiting the Gulf of Mexico, and is analyzed from Miami Florida to the Yucatan Channel. Isolated showers are in the extreme SE part of the Gulf, associated with the frontal boundary. Fresh to strong northerly winds will continue in the Bay of Campeche this morning. A strong cold front will move into the northern Gulf on Sunday, extend from southern Florida to the Yucatan peninsula on Monday, the move south of the area Tuesday. Fresh to strong northerly winds are expected across most of the region Sunday night through Tues. Strong winds may linger in the SE Gulf on Wednesday. CARIBBEAN SEA... A tropical wave is along 69W, from 22N southward, moving westward at 15 knots. A 1007 mb low is analyzed along the wave axis near 15N69W. This disturbance is slowly becoming better organized, and a tropical depression is likely to form this weekend as the system moves westward into the western Caribbean Sea. The chance of tropical cyclone formation during the next 48 hours is high. Please the Special Features section above for more details. A second tropical wave is about 240 nm west of the first wave along 73W, from 21N southward, moving westward at 10 to 15 kt. These two waves are expected to merge during the next 24 hours near 75W. The eastern extension of the monsoon trough in the eastern Pacific Ocean is along 09N to 11N, from 73W in northern Colombia across Panama into Costa Rica. Widely scattered moderate showers are noted south of 13N southward and from 73W westward. Little change in the position of the monsoon trough in the SW Caribbean is expected through Sunday. Developing low pressure along a tropical wave in the central Caribbean will shift westward into the western Caribbean, with widespread showers and thunderstorms expected. A tropical depression is likely to form this weekend as the system moves westward across the central and western Caribbean Sea. Heavy rainfall is possible in Central America early next week. ATLANTIC OCEAN... A cold front extends from Bermuda to Miami Florida. Isolated showers are evident within 180 nm northwest of the front, and scattered moderate convection is noted within 120 nm either side of a line from 32N63W to 22N76W. Broad surface anticyclonic wind flow covers the Atlantic Ocean from 20N northward, east of the cold front, associated with an elongated ridge of high pressure. Generally fair weather conditions prevail across the tropical Atlantic Ocean, from 18N to 32N between 38W and 62W. The existing cold front from Bermuda to Miami will stall and dissipate from 32N55W to the Florida Keys later today. A strong cold front will sweep across the forecast area Sunday night through Tuesday, with strong northerly winds and building seas expected behind the front. $$ Mundell