000 AXNT20 KNHC 171708 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Thu Sep 17 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 1600 UTC. ...SPECIAL FEATURES... Hurricane Teddy is centered near 19.3N 53.0W at 17/1500 UTC or 530 nm ENE of the Lesser Antilles moving NW at 10 kt. Estimated minimum central pressure is 957 mb. Maximum sustained wind speed has risen to 105 kt with gusts to 130 kt. Some additional strengthening is possible through tonight. A slow weakening trend is expected to begin over the weekend. The hurricane is expected to continue the same motion for the next few days. Numerous moderate to strong convection is located within 180 NM of the center. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT5.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMAT5.shtml for more details. Tropical Depression Vicky is centered near 21.4N 38.2W at 17/1500 UTC or 870 nm WNW of the Cabo Verde Islands moving W at 12 kt. Estimated minimum central pressure is 1008 mb. Maximum sustained wind speed has dropped to 30 kt with gusts to 40 kt. Additional weakening is forecast during the next day or so, and Vicky is expected to become a remnant low later today. A turn toward the west-southwest is expected later today, and that motion should continue through Friday. Scattered showers are located within 60 NM of the center. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT1.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMAT1.shtml for more details. A 1005 mb developing low pressure area in the SW Gulf of Mexico is centered near 22N96W. Thunderstorm activity has continued to increase and become better organized this morning with scattered moderate and isolated strong convection occurring from 20N-25N between 92W-98W. Upper-level winds are gradually becoming more conducive for development and, if this recent development trend continues, a tropical depression or a tropical storm could form later today. The low is expected to meander over the southwestern Gulf of Mexico for the next day or so before moving slowly northward to northeastward on Friday and Saturday. The potential for tropical cyclone formation is high over the next 48 hr. A Gale Warning has been issued in association with this system. Please read the latest High Seas Forecast: https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more information. A tropical wave is near 27W, south of 19N, moving westward around 10 knots. A 1010 mb low pressure center is along the tropical wave near 11N. Scattered moderate isolated strong convection is noted from 08N-12N between 20W-30W. Environmental conditions are expected to be conducive for development during the next few days, and a tropical depression could form before upper-level winds become less favorable over the weekend. The low is forecast to move west-northwestward at 10 to 15 kt during the next several days. The potential for tropical cyclone formation is medium over both 48 hr and 5 days. Please read the latest Tropical Weather Outlook, at https://www.nhc.noaa.gov/gtwo.php, for more details. ...MONSOON TROUGH/ITCZ... A small segment of the monsoon trough axis extends from the 1010 mb low near 21N27W to 07N36W. Scattered moderate isolated strong convection is noted from 08N-12N between 20W-30W. GULF OF MEXICO... See discussion of low in SW Gulf of Mexico in Special Features section. Elsewhere in the Gulf, a weak cold front extends from the Florida panhandle near 30N86W west-southwestward to 28N95W, where it transitions to a trough extending to the 1005 mb low at 22N96W. Scattered showers exist within 60 NM of the front and trough. W winds in the NE Gulf are moderate to strong due to the gradient induced by Tropical Depression Sally centered inland over Alabama and Georgia. Seas remain below 8 ft across the Gulf. The existing cold front over the N Gulf should weaken and dissipate by Fri. A new weak front will move into the northern Gulf on Sat, followed by fresh to strong east to northeast winds. CARIBBEAN SEA... Weak surface ridging to the north is inducing generally light to gentle trades across the Caribbean today. An upper-low is helping to promote isolated moderate convection from 12N-16N between 78W- 83W. Elsewhere scattered showers associated with a weak surface trough are impacting the Leeward Islands, Virgin Islands, and Puerto Rica as well as nearby waters from 15N-19N between 61W- 66W. The monsoon trough extends from the eastern Pacific Ocean across Panama/Costa Rica to near 11N75W. No significant showers are present with the trough. A relatively weak pressure pattern will maintain gentle to moderate trades through early next week, with fresh trades pulsing over the south-central Caribbean. ATLANTIC OCEAN... See discussion of Hurricane Teddy, Tropical Depression Vicky, and a tropical wave/low along 27W in the Special Features section. Away from the above three features, the trades remain generally gentle to moderate across the Atlantic. However, large swell of at least 8 ft are being generated by Hurricane Teddy, which are currently reaching the Leeward Islands the the NW coast of South America to the south and west and to 28N to the north. A cold front will move off the southeastern U.S. coast Fri night, then become nearly stationary on Sun. Strong northeast winds are expected north of the front, with building seas. The swell from Teddy will spread westward to the Greater Antilles, the Bahamas, Bermuda, and the east coast of the United States by the weekend. Large swell can cause life-threatening surf and rip current conditions. Please consult bulletins and messages from your local weather office. $$ Landsea