378 AXNT20 KNHC 111006 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Mon Jul 11 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 1000 UTC. ...TROPICAL WAVES... An eastern Atlantic tropical wave has its axis along 34W from 07N to 20N. It is moving westward at 10-15 kt. Convection with this wave remains suppressed as African dust surrounds this wave. Scattered moderate convection is limited to within 120 nm east of the wave from 07N-10N and within 60 nm east of the wave from 07N- 09N. An eastern Caribbean tropical wave has its axis along 66W south of 19N, moving westward at 15-20 kt. No significant deep convection is noted with this tropical wave. A western Caribbean tropical wave has its axis along 82W south of 21N to northern Panama. It is moving westward at 10-15 kt. This wave is situated to the southeast of an upper-level low that is near the western tip of Cuba. Divergence aloft between this low and the tropical wave is helping to sustain scattered moderate to isolated strong convection that is west of the wave axis from 12N to 14N west of the wave to just inland Nicaragua. Similar convection is along the coast of Honduras, north to near 18N. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Guinea near 11N15W just east of a a tropical wave axis near 10N34W. The ITCZ begins just west of the same tropical waves axis near 10N35W to 09N48W and to along the coast of Guyana at 09N60W. In addition to convection associated with the Atlantic tropical wave, scattered moderate to isolated strong is within 120 nm south of the ITCZ between 37W-49W. Scattered moderate convection is within 300 nm south of the trough between 20W-25W and within 180 nm south of the trough between 25W-28W. GULF OF MEXICO... A weak ridge continues to dominate the Gulf waters supporting mainly light and gentle winds, except moderate to locally fresh southerly winds over the far NW Gulf. A surface trough is analyzed from inland the Florida panhandle, south-southwest to Apalachicola and out over the Gulf to near 29N87W. Scattered showers and isolated thunderstorms are seen within 120 nm either side of the trough north of 28N. Isolated showers and thunderstorms are from 25N to 28N between 85W-89W. Areas of rain, with embedded scattered showers and isolated thunderstorms are from 21N to 25N between 87W-90W. Moderate to fresh northeast to east winds are just west of the Yucatan peninsula due to the an enhanced gradient related to the Yucatan Peninsula trough that has shifted to offshore the Yucatan Peninsula. Buoy observations along with recent altimeter data indicate seas of 3 ft or less throughout, except for higher seas of 3-5 ft in the central Bay of Campeche. For the forecast, surface ridging extending across the basin will maintain light to gentle return flow east of 90W through the forecast period, except over the far northeast part of the basin where a slighter tighter gradient near the aforementioned surface trough will support moderate to fresh southwest winds. Gentle to moderate southerly winds west of 94W will increase to moderate to fresh speeds at night through Thu, while diminishing back to gentle to moderate speeds by early in the afternoons as broad low pressure develops over Texas and northeastern Mexico. Light to gentle winds are expected across the Gulf on Fri, except over the eastern Bay of Campeche where winds will be enhanced by a thermal trough coming off the Yucatan peninsula at night. Southerly winds may be enhanced over sections of the north-central and NE Gulf from Wed through Fri night associated to the surface trough or to low pressure that may form from the trough. CARIBBEAN SEA... The pressure gradient between the Bermuda-Azores High located well northeast of the area and the Colombian Low supports fresh to strong northeast to east trade winds across much of the central Caribbean. A 1017 mb high is along the western tip of Cuba. Seas are in the 8-9 ft range with these winds based on overnight altimeter data passes. Mainly moderate trade winds along with seas of 5-7 ft are in the eastern Caribbean, while gentle northeast to east winds are over the northwestern Caribbean along with seas of 3-5 ft. An elongated upper-level low is identified on water vapor imagery to be over the northwestern Caribbean near 21N86W. It continues to support the development of showers and thunderstorms across parts of Cuba and the NW Bahamas and convection associated to the tropical wave along 82W as described above. This feature will also continue to aid in the development of showers and thunderstorms over South Florida today. The upper-level low will move into the far south-central Gulf of Mexico by early this evening. For the forecast, strong high pressure centered over the north- central Atlantic extending a ridge to the northern Caribbean will maintain moderate to fresh trade winds across the E basin, and fresh to strong winds in the central and portions of the SW basin through Fri night. These winds will be modulated by a pair of tropical waves moving across the area. Gentle to moderate winds in the northwestern Caribbean will increase to moderate to fresh on Tue, and reach strong speeds in the Gulf of Honduras on Tue night, continuing through Fri night. ATLANTIC OCEAN... The subtropical Bermuda-Azores High continues to dominate the Atlantic forecast waters, with the associated ridge extending toward the Bahamas and Florida. Moderate to locally fresh northeast to east trade winds are present between the ridge and the ITCZ. Seas are 6-8 ft south of 22N and 4-5 ft north of 22N. Strong to locally near gale force northerly winds are between the Canary Islands with moderate or rough seas. An altimeter pass across this area shows seas of 8 to 9 ft. CIMSS Saharan Air Layer (SAL) GOES-E images and the GOES16 RGB dust imagery indicate substantial amount of African dust east of 62W covering the majority of the tropical North Atlantic. For the forecast west of 55W, the Bermuda-Azores High will continue to extend a ridge southwestward across the region, which will maintain moderate to fresh easterly winds mainly south of 25N during the forecast period. Moderate to fresh southwest winds north of 29N associated with the passage of a frontal boundary north of the area will diminish slightly on Tue and continue through Thu. Afterwards, these winds become mainly gentle southeast to south through Fri night. $$ Aguirre