000 AXNT20 KNHC 201759 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Fri May 20 2022 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 31N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 1200 UTC surface analysis and satellite imagery through 1700 UTC. ...SPECIAL FEATURES... A Central American Gyre (CAG) is developing across Central America and the adjacent southwest Caribbean today. The monsoon trough has begun to shift northward, increasing SW winds and advecting tropical moisture over Central America. Heavy to extreme rainfall is possible over portions of Guatemala, El Salvador, Nicaragua, Honduras, Costa Rica, and Panama. There is potential for flash flooding and mudslides, especially across mountainous terrain. This event is expected to last through early next week. Please refer to products issued by your local weather service for more information. ...TROPICAL WAVES... A tropical wave is in the Atlantic with axis along 50W, from 01N to 14N moving west around 20-25 kt. Scattered moderate convection is noted from 00N-07N between 42W-53W. A tropical wave is in the far western Caribbean with axis south of 19N along 88W, moving west around 10 kt. Scattered moderate and isolated strong convection is noted south of 20N and west of 81W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the African coast near 12N15W to 09N20W. The ITCZ continues from 08N21W to 01N49W. Numerous moderate and scattered strong convection is noted from 03N-08W east of 26W. The eastern North Pacific's monsoon trough extends across Central America, reaching the coast near 11N84W near the border of Costa Rica and Honduras, and extending to 10N75W over Colombia. Scattered moderate and isolated strong convection is noted south of 20N west of 81W. ...GULF OF MEXICO... The gradient between the Bermuda High and lower pressure over NE Mexico is supporting moderate to fresh S to SE flow across the majority of the basin. Seas are 2-4 ft in the eastern Gulf and 3- 6 ft in the western Gulf. Divergent upper-level flow is supporting scattered moderate convection north of 26N and east of 86W. For the forecast, high pressure will build over the western Atlantic through Sun as low pressure develops over the Bay of Campeche. This will allow for mostly fresh southeast winds over the western Gulf to expand eastward tonight into Sat. Fresh to strong southeast winds from the northwestern Caribbean Sea will surge into the central Gulf waters and Yucatan Channel from from Sat through Sun, diminishing to fresh speeds Sun night. Elsewhere, Winds and seas will then diminish slightly across most of the basin Sun into Mon as the pressure gradient relaxes, leaving only pulses of fresh to occasionally strong winds at night off the northern and western Yucatan Peninsula. Fresh return flow is expected over the western Gulf Mon night through Tue night. ...CARIBBEAN SEA... Please see the Special Features section for information on a potential heavy rainfall event. The Bermuda High interacting with lower pressure over Central America associated with the developing Central American Gyre is forcing fresh to strong NE trades over the central and W Caribbean with moderate to fresh trades over the E Caribbean. Seas are 7-9 ft over the central Caribbean, 5-7 ft over the W Caribbean, and 3-6 ft over the E Caribbean. Scattered moderate and isolated strong convection is noted south of 20N west of 81W in association with a tropical wave and the developing Central American Gyre. For the forecast, winds and seas across the basin will increase tonight into the weekend as the western Atlantic ridge strengthens and broad low pressure over Central America gradually shifts west to northwestward. The strongest winds and highest seas are expected to be over parts of the northwestern and south-central Caribbean during this period. Looking ahead, winds and seas will start to diminish across the basin early next week as the pressure gradient relaxes. ...ATLANTIC OCEAN... Ridging associated with the Bermuda and Azores Highs stretches across the basin near 30N. Winds northwest of a line from 30N30W to 20N70W are gentle or weaker with seas 3-5 ft. Southeast of the line, the NE to E trades are moderate to fresh and with seas 6-9 ft. A dissipating cold front extends from 30N23W southwestward to 27N30W with showers occurring within 60 NM of the front. Scattered moderate convection is occurring between 23N-27N west of 75W, forced by upper-level divergent flow. For the forecast west of 55W, a surface ridge along 28N will lift north to 30N through tonight and strengthen. This pattern will support mainly gentle to moderate breezes across the region through early next week, except for moderate to fresh winds north of Hispaniola starting tonight. $$ Landsea/Aguirre