000 AXNT20 KNHC 170947 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 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 0600 UTC surface analysis and satellite imagery through 0930 UTC. ...SPECIAL FEATURES... Heavy Rainfall in SE Bahamas and Hispaniola: A nearly stationary mid-level low centered over eastern Cuba coupled with a moist trade-wind flow is triggering numerous moderate and scattered strong convection over the SE Bahamas. 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 through tonight, and over 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 could cause some flash flooding over portions of the southeastern and central Bahamas, eastern Cuba, and Hispaniola through Wed. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic Ocean through the coast of Guinea near 09.5N14W to 03N16W. The ITCZ continues from 03N16W to 02N32W to 01N49W. Numerous moderate to scattered strong convection is occurring from 00N-07N between 05W-15W. Scattered moderate isolated strong convection is noted from 00N-06N between 15W-28W, and from 00N-05N between 40W-49W. GULF OF MEXICO... Ridging prevails over the northern Gulf. Light to gentle anticyclonic winds are over the NE Gulf. Gentle to moderate SE winds are found in the NW Gulf. A diurnal trough moving westward from the northern Yucatan Peninsula is likely producing moderate to fresh E winds in the eastern Bay of Campeche. Seas are 3-5 ft over the SW Gulf, 2-4 ft over the NW Gulf, and 1-3 ft elsewhere. The latest surface observations show visibility 2 to 4 miles over portions of the northwest Gulf. Some of this may be due to haze or smoke caused by agricultural fires in Mexico. However, some of the reduction in visibility is being caused by fog and low stratus clouds. For the forecast, fresh NE to E winds will pulse at night west of the Yucatan Peninsula tonight and Mon night associated with a diurnal trough. Ridging will prevail over the remainder of the Gulf through tonight. 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. Patchy dense fog is also possible this morning across portions of the northwest Gulf. CARIBBEAN SEA... A mid-level low is triggering isolated moderate convection over portions of the north-central Caribbean, north of 13.5N between 69W-80W. Refer to the Special Features section for more information on the expected heavy rain across Hispaniola. Farther south, scattered strong convection is occurring over western Venezuela and northern Colombia. Some localized flooding from continued heavy rain appears possible over those areas as well during the next few days. Fresh to locally strong trades are occurring over most of the eastern and central Caribbean east of 73W, where seas are currently 6-8 ft. Moderate trades are found between 73W-79W, and mainly gentle winds are west of 79W, except for moderate in the Gulf of Honduras. Seas are 4-6 ft in the SW Caribbean and 2-4 ft in the NW basin. For the forecast, the pressure gradient between high pressure located well E of Bermuda and low pressure over Colombia will continue to support fresh to strong trades over the south-central Caribbean through this morning. 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... The combination of convergent moist trade winds and a pronounced mid-level low over E Cuba is producing heavy showers and thunderstorms over the SE Bahamas and nearby waters. Refer to the Special Features section for more information on this heavy rainfall event. High pressure ridging extends across the western Atlantic, leading to gentle to moderate wind speeds north of 27N between 55W-80W. Seas are 4-6 ft in this area. Farther south, fresh to locally strong trades prevail south of 24N between 55W-72W, where seas are 8-9 ft. For the forecast west of 55W, fresh to strong 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. Farther east, a 1016 mb low pressure is centered near 31N34W. An associated cold front extends from 31N31W to 26.5N33W to 24N41W to 28N49W. Strong N winds are present on the west side of the low pressure, north of 29N between 35W-40W. Fresh NE to E winds are elsewhere to the north of the cold front. Recent altimeter data from 17/0730 UTC shows seas of 13-14 ft from 30.5N-31N between 35W-35.5W. Seas are likely in excess of 8 ft north of 25N and east of 51W. For the forecast east of 55W, the low pressure near 31N34W will weaken as it moves southward into the area today, but will still have strong winds on its west side through tonight. After the low dissipates tonight, the gradient will increase to the east, brining strong to near gale force NE to E winds north of 27N east of 35W early next week. Seas will build to 11-15 ft in this area late Mon through Tue. $$ Hagen