000 AXNT20 KNHC 112307 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Wed Jun 12 2024 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 1800 UTC surface analysis and satellite imagery through 2200 UTC. ...SPECIAL FEATURES... Heavy Rainfall in the NW Caribbean, SE Gulf of Mexico, and South Florida: Abundant tropical moisture is surging northward from the western Caribbean, across the SE Gulf of Mexico, across the south half of Florida, and into the adjacent western Atlantic. This moisture is focusing about a trough of low pressure over the SE Gulf, and combining with upper-level diffluent flow across the region to support a band of scattered to numerous showers and thunderstorms extending from the northern Yucatan Peninsula northeastward across the SE Gulf of Mexico, across southern Florida and into the western Atlantic west of 75W. Dangerous cloud to ground lightning, strong gusty winds, rough seas and low visibility are ongoing within this convective activity over these areas. Heavy rainfall across south Florida today has warranted Flood Watches and Flash Flood Warnings. This convection is expected to continue across the region through Fri. Mariners transiting these regions should exercise caution. Please refer to bulletins and forecasts from your local weather forecast offices for specific local information. ...TROPICAL WAVES... A tropical wave in the eastern Atlantic extends along 30N-31N south of 15N, moving westward near 15 kt. Scattered moderate to strong convection is depicted from 4.5N to 8N between 25W and 31W. A tropical wave is moving across the E Caribbean S of 13N with axis near 65W, moving westward at 10-15 kt. Scattered moderate isolated strong convection follows the wave, from 12N to 14N between 62W and 67W. Saharan Air is north of the wave to near 19W and extends eastward into the tropical Atlantic. A tropical wave is analyzed in the south-central Caribbean Sea along 76W, south of 15N, and moving westward at 10-15 kt. This wave is becoming ill defined as it encounters low to middle level southeast wind flow surging into the NW Caribbean. A cluster of moderate to strong convection is along the wave from 11N to 12.5N between 76W and 79W. Saharan Air dominates the low to middle atmosphere in the area N of 14N. ...MONSOON TROUGH/ITCZ... The monsoon trough reaches the Atlantic through the coast of Guinea-Bissau near 12.N16.5W and continues southwestward to 09N19W. The ITCZ extends from 09N19W to 05N51W. Scattered to numerous moderate to strong convection is from 04.5N to 09N between 18W and 31W. Scattered moderate isolated strong convection extends from 02N to 08N between 36W and 58W. ...GULF OF MEXICO... Please read the Special Features section for information about heavy rainfall in the SE Gulf of Mexico. A middle to upper level trough extends from the SE U.S. to just north of the Yucatan coast and is creating a very unstable environment. Abundant moisture from the Caribbean is converging about a low level trough that extends from the Yucatan Peninsula to low pressure of 1010 mb offshore of western Florida near 27N84W. Scattered to numerous moderate to strong convection continue along and southeast of the low level trough, which is also depicted at the surface. Fresh to locally strong S to SW winds prevail to the east of this surface trough and into the SW coast of Florida. Seas across this area are 3 to 6 ft. Elsewhere, a stationary front lingers along the northern Gulf coasts from Florida to SE Texas. Light concentrations of smoke continue over the western Gulf, including the Bay of Campeche, due to ongoing agricultural fires in Mexico, creating hazy conditions. Light to gentle NE to N winds generally prevail west of the surface trough, with slight seas. For the forecast, the aforementioned trough of low pressure is expected to meander across central Florida and the eastern Gulf during the next day or so. Fresh to locally strong southerly winds are expected through Wed over the SE Gulf on the SE side of this system. Hazy conditions, due to agricultural fires over Mexico, will continue to affect the western Gulf reducing visibility to around 3 nm at times, during the next couple of days. Broad low pressure and active weather are expected to continue across the southern Gulf of Mexico throughout the week. ...CARIBBEAN SEA... Please read the Special Features section for information about heavy rainfall in the NW Caribbean. The pressure gradient between Atlantic high pressure, lower pressures in the deep tropics, and the trough of low pressure across the SE Gulf of Mexico is resulting in fresh to strong E to SE trade winds over the east and central basin and moderate to fresh SE to S winds across NW portions. Seas are 7-9 ft over the central Caribbean and 4 to 7 ft elsewhere. Moderate to strong convection continues across NW portions, from 20N northward across western Cuba to the NE Yucatan coast. For the forecast, high pressure centered across the NE Atlantic will maintain a ridge to the Bahamas, and combine with the Colombian low and the passage of tropical waves to support fresh to strong trade winds across the central Caribbean through Thu night. Moderate to fresh SE to S winds are expected over the NW Caribbean likely through Fri as a trough of low pressure remains over the eastern Gulf of Mexico. Otherwise, scattered showers and thunderstorms are forecast to continue across portions of the NW Caribbean this work-week as surging of tropical moisture persists across the region. ...ATLANTIC OCEAN... A trough of low pressure over the eastern Gulf of Mexico extends northeastward across central Florida and into the adjacent Atlantic to near 29N79W. Converging low level moisture southeast of this feature is producing a large area of disorganized showers and thunderstorms over S Florida, the FLorida Keys, extending into the Atlantic N of 24N and west of 72W. High pressure is centered across the NE Atlantic near 39N32W and extends a ridge southwestward to the central Bahamas. The pressure gradient between this ridge, the surface trough, and a stationary front off the SE United States supports moderate to locally fresh S to SW winds north of 26N and west of 68W. Seas in these waters are 4 to 7 ft. The remainder of the subtropical Atlantic is under the influence of this 1031 mb Azores high, which is supporting mainly fresh NE winds between the coast of W Africa and the Cape Verde Islands. South of the ridge, moderate to locally fresh trades are ongoing in the tropical Atlantic waters, where seas are 4 to 6 ft. Saharan Air dominates the lower to middle atmosphere across the Atlantic, from 10N to 20N between Africa and the Lesser Antilles. For the forecast W of 55W, the low pressure offshore of the west coast of Florida is expected to move northeastward across Florida during the next day or so, and enter the Atlantic waters offshore of the U.S. Southeast coast later this week. Environmental conditions are expected to be generally unfavorable for any tropical development in the short term, although some slow development is possible when the system is offshore of the U.S. Southeast coast later in the week. Heavy rainfall is already occurring and is expected to continue across portions of Florida and the Atlantic west of 75W during the next few days. Fresh to strong southerly winds are expected over the western Atlantic ahead of this system over the next couple of days. $$ Stripling