000 AXNT20 KNHC 171600 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Sun Apr 17 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 1600 UTC. ...SPECIAL FEATURES... Heavy Rainfall in SE Bahamas, Turks and Caicos and Hispaniola: A nearly stationary mid-level low is supporting a surface trough in the Windward Passage. This feature, coupled with moist trade- wind flow, is triggering numerous moderate and scattered strong convection over the SE Bahamas and Turks and Caicos. This convection is expected to gradually spread southeastward over Hispaniola this afternoon and evening. Enhanced by favorable upper-level winds, periods of heavy rainfall are anticipated for the SE Bahamas and Turks and Caicos through tonight, and over Turks and Caicos and Hispaniola this evening through Tue. Looking further ahead, a robust mid-latitude trough digging southeastward from offshore the SE U.S. toward the Caribbean Sea will reinforce the mid-level trough and upper-level diffluence over the same area during midweek. As a result, this rainy pattern could persist through midweek. These rains have to potential to cause flash flooding over portions of the southeastern and central Bahamas, Turks and Caicos, eastern Cuba and Hispaniola through Wed. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the eastern Atlantic Ocean through the coast of Sierra Leone near 08N13W to 03N21W. The ITCZ continues from 03N21W, crossing the equator near 31W, to the coast of Brazil near 02S42W. Scattered moderate with isolated strong convection is occurring from the equator to 07N between 05W-20W. Scattered moderate convection is noted from the equator to 06N between 20W- 30W, and from 02N-05N between 41W-47W. GULF OF MEXICO... A weak gradient between low pressure over Mexico and higher pressure in the western Atlantic is causing light to gentle SW flow across the basin with slight to moderate seas. Patchy fog is being reported in the northwest Gulf with visibilities of 2 to 4 miles. For the forecast, a weak Atlc ridge extends across N Florida to the NW Gulf and will persist through early Mon. Fresh NE to E winds will pulse during the evening and along the NW Yucatan Peninsula waters through Mon night associated with a diurnal trough. A cold front will move into the northern Gulf early Mon, then stall across the southern Gulf late Tue through Wed. Fresh to locally strong N to NE winds and building seas will follow the front. Meanwhile, patchy areas of smoke may reduce visibility across portions of the Mexican offshore waters W of 95W and off southern Texas. CARIBBEAN SEA... The gradient between high pressure over the subtropical Atlantic and a 1009 mb low over northern Colombia is supporting moderate to fresh easterly winds over the eastern Caribbean. The gradient weakens west of 76W where winds are light to gentle. Seas are 6-8 ft in the eastern Caribbean, 4-6 ft in the SW Caribbean and 2-4 ft in the NW Caribbean. A surface through the windward passage is triggering scattered thunderstorms east of Jamaica from 73W-77W between 14N-20N. For the forecast, a broad trough is expected to develop from coastal Colombia to E Cuba along 76W Mon through Tue night. Heavy showers and thunderstorms are expected across the north-central and NE Caribbean tonight through Tue. Looking ahead, a cold front will reach the Yucatan Channel by early Wed and stall there through Thu night. ATLANTIC OCEAN... Refer to the Special Features section for information on the heavy rainfall event affecting the SE Bahamas, Turks and Caicos, eastern Cuba and Hispaniola. High pressure ridging in the western Atlantic is causing gentle to moderate SE wind and 4-6 ft seas north of 27N with moderate to fresh easterly winds and 6-9 ft seas south of 27N. In the central Atlantic, a 1018 mb low pressure centered near 30N34W is generating strong, but weakening, NE winds extending roughly 300 nm NW of the circulation. Seas are 10-13 ft in the area of strong winds. An occluded front wraps around the low pressure from 31N32W to 28N31W where it becomes a cold front and continues through 23N40W to 28N50W. Moderate to fresh NE winds and rough seas seas prevail behind this front with moderate winds to the south. In the eastern Atlantic, fresh NE winds along 31N quickly decrease to gentle south of the Canary Islands. For the forecast west of 55W, fresh trade winds south of 24N and E of the Bahamas will diminish slightly today as high pressure well E of Bermuda shifts eastward. Meanwhile, a trough will form over the Bahamas along 76W-77W on Mon. Low pressure will form along this trough Mon night east of the NW Bahamas, then shift northward Tue ahead of a cold front moving off the northeast Florida coast by Mon night. The front will reach from Bermuda to the central Bahamas to west-central Cuba by Wed. Fresh to strong NE winds and building seas will follow the front. $$ Flynn