AXNT20 KNHC 242317

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0005 UTC Sat May 25 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 2300 UTC.


Significant Rainfall Event in the Caribbean: Satellite imagery shows that a weak area of low pressure has formed several hundred miles southwest of Bermuda near 25.5N70W. This system is accompanied by disorganized showers and thunderstorms. Although environmental conditions are not conducive, some slight subtropical or tropical development is possible over the next couple of days while the system moves generally northeastward. Aloft, a very pronounced deep-layered trough extends southwestward from 30N73W across eastern Cuba and into the SW Caribbean Sea limiting the tropical development in the area. A band of moisture will persist ahead of the trough axis over Hispaniola, Puerto Rico and the US/UK Virgin Islands. Locally heavy rain may occur over these locations through the upcoming weekend, particularly over Hispaniola. Residents in the above locations should remain alert for significant rainfall and potential flash flooding. Please refer to your local weather office for more specific information.


The first tropical wave of the season has its axis along 55W from 12N southward, moving west at 10-15 kt. Scattered moderate isolated strong convection is noted on either side of the wave axis S of 10N. The wave appears to enhance convection over parts of French Guiana and Suriname. Latest scatterometer pass captured the wind shift associated with the wave axis. The wave will cross the Windward Islands on Sat. Gusty winds and active weather are expected with the wave.

Of note: On average, about 60 waves are generated over North Africa each year, but it appears that the number that is formed has no relationship to how much tropical cyclone activity there is over the Atlantic each year. While only 60% of the Atlantic tropical storms and minor hurricanes originate from easterly waves, nearly 85% of the intense (or major) hurricanes have their origins as easterly waves.


A monsoon trough enters the Atlantic near 14N16W, then continues SW to 05N22W. The ITCZ extends from 05N22W to near the Brazil/ French Guiana border. Scattered moderate to isolated strong convection is from 02N to 05N between 40W and 40W, and from 02N to 10N between 47W and 58W.


A ridge dominates the Gulf waters producing moderate to fresh SE winds over the western half of the Gulf with seas of 3 to 5 ft, and gentle to moderate SE winds over the eastern half of it with seas of 1 to 3 ft. The latest surface observations confirm reduced visibilities and hazy conditions across the western Gulf, due to smoke from agricultural fires over southern Mexico. In addition, visible satellite imagery also confirmed the presence of the smoke extending northward from the Bay of Campeche creating hazy conditions.

For the forecast, high pressure over the region will begin to shift east-southeastward starting Sun. Moderate to fresh winds over the western Gulf, and gentle to moderate winds over the eastern Gulf are expected to continue through the weekend, except for winds becoming light and variable over most of the eastern Gulf through early next week. A cold front will move across the NE Gulf from late Tue through Wed night, followed by gentle to moderate west to northwest winds. Fresh to strong winds will pulse near the northern and western Yucatan Peninsula during the late afternoons and at night through the period.


Please read the Special Features section about a Significant Rainfall Event impacting Hispaniola and Puerto Rico.

Scattered showers are isolated thunderstorms are noted over parts of Hispaniola and Puerto Rico. Convection has also flared-up over northern Colombia and western Venezuela. A diffluent pattern aloft supports this convective activity. Recent satellite scatterometer data indicates moderate to fresh E to SE winds in the Gulf of Honduras, where smoke from agricultural fires in Honduras continues to reduce visibilities to 3 nm. Please exercise caution in areas of dense smoke. Elsewhere, light to gentle trades are noted across the basin, with the exception of moderate winds over the far SE Caribbean. Seas are generally in the 3 to 5 ft range.

For the forecast, the very pronounced deep-layer trough previously mentioned will lift east-northeastward across Hispaniola through Sat night. Active weather east of the trough will gradually shift northeastward into the Atlantic through Sat night. A rather weak pressure pattern across the region will maintain generally moderate trade winds across the basin, except for moderate to fresh winds over the northwestern part of the Caribbean Sea through late Sun night. Afterwards, moderate to fresh trade winds are expected over the Caribbean through the middle of next week, except for light to gentle winds over the northern part of the northwestern Caribbean. The wave, currently along 55W will cross the Windward Islands late Sat afternoon into Sat night, move through the eastern Caribbean Sun through Mon night, then become ill-defined as it approaches the central Caribbean Tue. Gusty winds and active weather are expected with the wave. Smoke due to agricultural fires in Central America may persist across the Gulf of Honduras tonight into Sat.


The deep-layered trough responsible for heavy rainfall across Hispaniola continues to move north and east away from the Greater Antilles. At the surface, 1012 mb low pressure is centered near 25.5N70W, along a surface trough extending from 28N62W to the low center to eastern Cuba. Scattered showers with embedded thunderstorms are associated with these systems affecting mainly the waters N of 20N between 60W and 72W. The trough is helping to induce some convective activity over eastern Cuba. High pressure dominates the remainder of the Atlantic forecast waters. Based on satellite derived wind data, mainly gentle to moderate winds are noted N of 20N while moderate to locally fresh trades are S of 20N. Seas are generally 4 to 7 ft in open waters.

For the forecast west of 55W, regarding the aforementioned low, although environmental conditions are not conducive, some slight subtropical or tropical development is possible over the next couple of days while the system moves generally northeastward. Otherwise, relatively weak high pressure will remain over the region for the next few days. Looking ahead, moderate winds and seas are possible north of the Bahamas and off northeast Florida by Mon night as the high pressure shifts eastward ahead of a cold front expected to move off the southeast U.S. coast Mon night, move across the waters east of northern Florida early on Tue, reach from near 31N79W to east-central Florida early on Wed and from near 31N78W to 29N79W and stationary to east-central Florida Wed night.

$$ GR