--------------------------------------------------------------------------- TROPICAL WEATHER DISCUSSION (NORTH ATLANTIC AREA) MESSAGES T1T2: AX A1A2: NT Date: 2025-09-15 --------------------------------------------------------------------------- Message File: T_AXNT20KNHC150340_C_KWBC_20250915034105_25559334-8648-TWDAT.txt ****0000004755**** AXNT20 KNHC 150340 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0615 UTC Mon Sep 15 2025 Tropical Weather Discussion for North America, Central America Gulf of America, 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 0000 UTC surface analysis and satellite imagery through 0345 UTC. ...TROPICAL WAVES... The axis of a far eastern Atlantic tropical wave is near 35W from 01N to 20N, with a 1012 mb low where the tropical wave intersects the monsoon trough. This system is moving westward at around 10 to 15 kt. Scattered moderate to isolated strong convection is noted from 04N to 16N between 30W and 40W. Although dry and stable air is expected to limit development during the next day or so, gradual development is anticipated thereafter, and a tropical depression is likely to form during the middle to latter part of this week as the system moves west-northwestward at 10 to 15 mph over the central tropical Atlantic. There is a low chance of development within the next 48 hours and a high chance within the next 7 days. The axis of a central Atlantic tropical wave is near 48W from 01N to 20N. It is moving westward at around 10 to 15 kt. Scattered moderate and isolated strong convection is noted from 14N to 20N between 45W and 50W. The axis of an eastern Caribbean tropical wave is near 68W south of 20N. It is moving westward at around 15 kt. Scattered moderate convection is noted from 15N to 17N between 65W and 68W. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic near 18N16W and continues southwestward through a 1012 mb low near 10.5N35W to 10N40W. The ITCZ continues from 10N40W to 10N47W. It resumes from 10N50W to 10N61W. Aside from convection described in the tropical waves section above, scattered moderate and isolated strong convection is noted from 04N to 10N east of 30W, and from 05N to 09N between 40W and 47W. ...GULF OF AMERICA... High pressure dominates the Gulf basin. Gentle to moderate anticyclonic wind flow prevails. Seas are in the 1-3 ft range. For the forecast, high pressure will dominate the basin through the week supporting mainly gentle to moderate winds. Winds will freshen in the N-central and NW Gulf Mon night as the high gets reinforced. Moderate to locally fresh winds will pulse offshore the Yucatan Peninsula each night. Winds may increase to moderate to fresh in the SE Gulf and Straits of Florida by Wed night due to a passing tropical wave just to the S combined with a stationary front or coastal trough off the SE U.S. coast. ...CARIBBEAN SEA... Fresh to strong winds prevail over the south central Caribbean. Moderate winds are elsewhere E of 80W. Over the western Caribbean, gentle to moderate winds are noted. Seas are in the 3-5 ft range E of 80W, and 1-2 ft W of 80W. For the forecast, a tropical wave in the central Caribbean will move through the western Caribbean Tue night through Thu night. Expect fresh winds over the central Caribbean Mon through Tue in the wake of the tropical wave. Scattered showers and isolated thunderstorms will accompany the wave. Fresh to strong winds will pulse in the S-central waters through mid-week. Otherwise, gentle to moderate trades, and mostly moderate seas will remain through the week, except slight to moderate seas in the NW Caribbean. ...ATLANTIC OCEAN... A surface trough extends over the western waters, from 31N74W to the Straits of Florida. Moderate winds, and seas of 6-8 ft prevail W of the trough. High pressure dominates the remainder of the discussion waters N of 20N, anchored by a 1029 mb high centered near 37N34W. Moderate to fresh winds prevail over the waters N of 15N and E of 50W, where seas are in the 4-7 ft range. Elsewhere, gentle to moderate winds, and seas of 3-5 ft are noted. For the forecast west of 55W, the trough will weaken through Mon. Otherwise, Atlantic high pressure will generally maintain moderate winds and seas elsewhere across the region through the week. A tropical wave over the eastern tropical Atlantic is likely to develop into a tropical depression during the middle to latter part of this week as the system moves west- northwestward over the central tropical Atlantic. Regardless of development, expect increasing winds and building seas over the southeastern waters by the end of the week. $$ AL ########################### END OF MESSAGE SET ############################ --------------------------------------------------------------------------- Message File: T_AXNT20KNHC151047_C_KWBC_20250915104822_12124482-2311-TWDAT.txt ****0000006307**** AXNT20 KNHC 151047 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1215 UTC Mon Sep 15 2025 Tropical Weather Discussion for North America, Central America Gulf of America, 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 1030 UTC. ...TROPICAL WAVES... The axis of a far eastern Atlantic tropical wave is near 36W from 01N to 20N, with a 1011 mb low where the tropical wave intersects the monsoon trough, or roughly near 11N36W. This system is moving westward at 10 to 15 kt. Fresh to strong northeast to east winds are on either side the wave and low from 14N to 20N between 35W and 40W. Seas with these winds are reaching to 8 ft. Satellite imagery shows increasing numerous moderate to strong convection over an area from 12N to 16N between 33W and 43W. Scattered moderate convection is from 06N to 10N between 30W and the wave. Although dry and stable air is expected to limit development during the next day or so, gradual development is anticipated thereafter, and a tropical depression is likely to form by the middle to latter part of this week as the system moves west- northwestward across the central tropical Atlantic. There is a low chance of development within the next 48 hours and a high chance within the next 7 days. The axis of a central Atlantic tropical wave is near 50W from 01N to 21N. It is moving westward at 10 to 15 kt. Scattered moderate convection is seen from 14N to 21N between 49W and 52W. The axis of a central Caribbean tropical wave is near 70W south of 20N. It is moving westward around 15 kt. Scattered showers and isolated thunderstorms are from 14N to 18N between 68W and 71W. ...MONSOON TROUGH/ITCZ... The monsoon trough axis enters the Atlantic near 17N16W and continues southwestward through a 1011 mb low near 11N36W to 10N42W, where it transitions to the ITCZ and continues to 10N49W and briefly pauses. It resumes at 10N51W to 09N60W. Aside from convection described in the tropical waves section above, scattered moderate convection is noted from 04N to 09N between 38W ad 45W. Similar activity is south of the trough from 10N to 14N between the coast of Africa and 20W. ...GULF OF AMERICA... High pressure dominates the Gulf basin. Overnight scatterometer satellite data passes reveal that gentle to moderate anticyclonic wind flow prevails. Seas are in the 2 to 4 ft range, except for slightly higher seas of 3 to 5 ft in the north-central Gulf. For the forecast, the high pressure will continue to dominate the basin through the week supporting mainly gentle to moderate winds. Winds will freshen in the N-central and NW Gulf tonight as the high pressure is replaced by stronger high pressure. Moderate to locally fresh winds will pulse offshore the Yucatan Peninsula each night. Winds may increase to moderate to fresh in the SE Gulf and Straits of Florida by Wed night due to the gradient related to a tropical wave that will be moving through the western Caribbean Sea. ...CARIBBEAN SEA... Fresh to strong winds prevail over the south central Caribbean as seen in an overnight scatterometer satellite data pass. Moderate winds are elsewhere E of 80W. Gentle to moderate winds are over the western section of the sea. Seas are in the 3-5 ft range E of 80W, and 1-2 ft W of 80W. For the forecast, a tropical wave along 70W will move across the central Caribbean through Tue, and through the western Caribbean Tue night through Thu night. Expect fresh trades over the central Caribbean Mon through Tue in the wake of the tropical wave. Scattered showers and isolated thunderstorms will accompany the wave. Another tropical wave is expected to enter the eastern Caribbean Tue or Wed. Fresh to strong winds will pulse in the S-central waters through mid-week. Otherwise, gentle to moderate trades, and mostly moderate seas will remain through the week, except slight to moderate seas in the NW Caribbean. ...ATLANTIC OCEAN... A surface trough extends over the western waters from low pressure that is N of the area near 33N74W, south-southwest to 31N74.5W, to the northern Bahamas and to near 24N80W. Moderate winds along with seas of 6-8 ft prevail W of the trough. High pressure dominates the remainder of the discussion waters N of 20N, anchored by a 1027 mb high that is centered well N of the region near 36N33W. Moderate to fresh trades are over the waters from 15N to 25N E of 65W, where seas are in the 5 to 7 ft range. Elsewhere, gentle to moderate winds, and seas of 3 to 5 ft are noted, except near the far eastern tropical wave and low pressure as described above. An area of scattered to numerous showers and thunderstorms is to the E of the trough from 25N to 31N between 57W and 65W. For the forecast west of 55W, the aforementioned trough will gradually weaken through Tue, but as the low lifts northward during the week, indications are that it will allow for the remnants of the trough to slowly lift back to the N providing for additional shower and thunderstorm activity over some of the zones in the western half of the region. Otherwise, Atlantic high pressure will generally maintain moderate winds and seas elsewhere across the region through the week. Looking ahead, a tropical wave over the the central tropical Atlantic is producing a large area of disorganized showers and thunderstorms. Although dry and stable air is expected to limit development during the next day or so, gradual development is anticipated thereafter, and a tropical depression is likely to form by the middle to latter part of this week as the system moves west-northwestward over the central tropical Atlantic. Regardless of development, expect increasing winds and building seas over the southeastern waters by the end of the week. $$ Aguirre ########################### END OF MESSAGE SET ############################