|
TROPICAL WEATHER OUTLOOK
Issued by the NWS Weather Prediction Center College Park MD200 PM EDT Thu Sep 4 2025
For the North Atlantic...Caribbean Sea and the Gulf of America:Tropical Atlantic (AL91):A broad area of low pressure has formed along a tropical wave over the eastern tropical Atlantic. Recent satellite imagery suggests the system continues to slowly become better organized with shower and thunderstorm activity along its eastern periphery. Environmental conditions are favorable for additional development of the system and a tropical depression is likely to form by this weekend as it moves slowly westward at 5 to 10 mph across the eastern and central tropical Atlantic. Interests in the Lesser Antilles and Leeward Islands should monitor the progress of this system as it approaches from the east by the middle of next week. * Formation chance through 48 hours...medium...60 percent. * Formation chance through 7 days...high...90 percent. TROPICAL WEATHER DISCUSSION
Tropical Weather DiscussionNWS National Hurricane Center Miami FL1815 UTC Thu Sep 4 2025Tropical Weather Discussion for North America, Central AmericaGulf of America, Caribbean Sea, northern sections of SouthAmerica, and Atlantic Ocean to the African coast from theEquator to 31N. The following information is based on satelliteimagery, weather observations, radar and meteorological analysis.Based on 1200 UTC surface analysis and satellite imagery through 1500 UTC
.SPECIAL FEATURES Eastern Tropical Atlantic:An eastern Atlantic tropical wave is along 36W, south of 19N,moving westward at 10-15 kt. Scattered moderate convection isobserved from 12N to 14N and between 30W and 35W. Environmental conditions are conducive for development of this system during thenext several days, and a tropical depression is likely to form late this week or this weekend over the eastern or central tropical Atlantic. There is a medium chance of formation within the next 2 days, and a high chance within the next 7 days. Refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details .TROPICAL WAVES Refer to the Special Features section above on an eastern Atlantic tropical wave.An eastern Caribbean tropical wave is along 62W south of 21N, andmoving westward at 10-15 kt. Scattered moderate convection isactive from 12N to 14N between 62W and 64W .MONSOON TROUGH/ITCZ A monsoon trough enters the Atlantic through the coast ofMauritania near 17N16W and continues southwestward to 1011 mb lowpressure near 12N33W, then westward to near 09N45W. An ITCZ extends from 09N45W to 09N60W. Scattered moderate convection is present from 06N to 09N between 15W and 25W, and 08N to 11N between 42W and 47W .GULF OF AMERICA A frontal trough extends from the Florida Keys to 1009 mb lowpressure in the east-central Gulf near 27N86W to 24N93W. Scatteredshowers and thunderstorms cover much of the eastern Gulf to thesouth of the trough. Moderate E winds and 3 to 4 ft seas areevident across the southeast Gulf, south of the low pressure.Light to gentle to breezes and slight seas are noted elsewhere. For the forecast, the frontal trough will persist over the east-central Gulf through Sat and continue to generate scattered to numerous showers and isolated thunderstorms, mainly across the eastern partof the basin. A cold front is forecast to enter the northern Gulfwaters on Sun, becoming stationary early next week. Winds and seas will increase in the NE Gulf behind the front, especially by the middle of next week. Elsewhere, a weak pressure gradient in place will maintain gentle to moderate winds with slight to locally moderate seas through the forecast period. CARIBBEAN SEA In addition to the scattered showers and thunderstorms ahead of the tropical wave in the southeast Caribbean west of the WindwardIslands, scattered convection is also ongoing over the farsouthwest Caribbean off Panama and Costa Rica associated withconvergent low level trade wind flow north of the monsoon trough.Farther north, a small cluster of thunderstorms is active offsoutheast Cuba in the Gulf of Guacanayabo related divergent flowaloft and local morning land breeze convergence. Moderate tradeconvergence and 3 to 5 ft seas cover much of the eastern andcentral Caribbean, except for fresh trade winds and 5 to 7 ft seasoff Colombia. Light to gentle breezes and 1 to 3 ft seas areobserved over the northwest Caribbean.For the forecast, the subtropical ridge will continue to force moderate to fresh easterly trade winds along with moderate seas across much of the central Caribbean through early Sun. Fresh to locally strong winds are expected to pulse off Colombia and the Gulf of Venezuela at night through Fri night. In addition, moderate to locally fresh E winds and slight to moderate seas willprevail in the Gulf of Honduras through Sat night. A tropical wave will move into the eastern Caribbean today, continue westwardinto the central Caribbean this weekend and across the western Caribbean early next week. Convection associated with this tropical wave is currently limited . ATLANTIC OCEAN Please read the Special Features section about the potential development of a tropical depression in the eastern and central Atlantic.A stationary front extends from 1009 mb low pressure over thenorth-central Atlantic near 46N37W, to off the eastern seaboard ofthe United States, then across the northern Bahamas and South Florida and into the far southeast Gulf of America. Scatteredshowers and thunderstorms are active with 90 nm east of the frontsouth of 31N. Farther east, a cold-core mid to upper level low iscentered near 24N60W, supporting scattered showers and thunderstorms within a 240 nm radius. An associated surface troughextends from 27N55W to 24N59W. As discussed in the SpecialFeatures section above, a 1011 mb low pressure is analyzed near 12N133W, close to where a tropical wave is interacting with themonsoon trough. A recent scatterometer satellite pass indicatedfresh winds within 90 nm of this low pressure center. Broadridging dominates the remainder of the subtropical Atlantic northof 25N, anchored by 1027 mb high pressure centered near 34N40W.This pattern is supporting generally moderate winds and seaselsewhere across the basin, except for fresh to strong NE windsand locally rough seas off northwest Africa. For the forecast west of 55W, the frontal boundary will persisteast of Florida through the weekend, but will drift westward as the Atlantic high pressure moves also westward over the next few days. Moderate to fresh S winds are expected ahead of the boundarythrough late today. Scattered to numerous showers and thunderstorms E of the front are affecting the NW Bahamas, South Florida, the Straits of Florida and Cuba. Unsettled weather conditions will continue ahead of the front over the next few days. Stronger winds and higher seas are likely near thunderstorms. Elsewhere, the Atlantic ridge will continue to dominate the weather pattern across the forecast waters, supporting gentle to moderate winds and mostly moderate seas. |
Mesoscale Discussion 2032 NWS Storm Prediction Center Norman OK 0119 PM CDT Thu Sep 04 2025 Areas affected... parts of middle/eastern Tennessee Concerning... Severe potential... Watch unlikely Valid 041819Z - 042045Z Probability of Watch Issuance... 20 percent SUMMARY... Occasional intensification of thunderstorms posing a risk for severe hail and localized damaging wind gusts may continue through late afternoon. Although the severe threat still appears mostly marginal in nature, and severe weather watch unlikely to be required, trends are continuing to be monitored.
Mesoscale Discussion 2031 NWS Storm Prediction Center Norman OK 1241 PM CDT Thu Sep 04 2025 Areas affected... parts of southwestern through north central Virginia... northwestern North Carolina Concerning... Severe potential... Watch unlikely Valid 041741Z - 041945Z Probability of Watch Issuance... 20 percent SUMMARY... Developing thunderstorm activity may increasingly pose a risk for sporadic damaging wind gusts through late afternoon. This seems unlikely to require a severe weather watch, but trends are being monitored.
