000 AXNT20 KNHC 151837 TWDAT Tropical Weather Discussion...UPDATED NWS National Hurricane Center Miami FL 1805 UTC Tue Jun 15 2021 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. Updated to include latest Tropical Weather Outlook Based on 1200 UTC surface analysis and satellite imagery through 1700 UTC. ...SPECIAL FEATURES... Tropical Storm Bill is centered near 40.5N 62.0W at 15/1500 UTC moving NE at 33 kt. Estimated minimum central pressure is 998 mb. Maximum sustained wind speed is 50 kt with gusts to 60 kt. Bill is a sheared tropical storm and scattered moderate convection is noted from 40N to 45N between 58W and 64W. Bill is forecast to maintain strength through the afternoon, then is forecast to weaken and become post tropical later this evening and dissipate by Wednesday. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT2.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMAT2.shtml for more details. Disorganized showers and thunderstorms continue over the Bay of Campeche and southern Mexico in association with a broad low pressure area. This system is expected to move little during the next day or two, and any development should be slow to occur during that time period due its close proximity to land. However, the disturbance should begin to move northward by Thursday, and a tropical depression is likely to form late in the week when the low moves across the central or northwestern Gulf of Mexico. Regardless of development, heavy rainfall will continue over portions of Central America and southern Mexico during the next several days. Heavy rains could also begin to impact portions of the northern Gulf Coast on Friday. Please consult products from your local meteorological service for more information. The latest Tropical Weather Outlook gives this system a medium chance of tropical cyclone formation trough 48 hours, and a high chance through 5 days. Please see the latest Tropical Weather Outlook at hurricane.gov ...TROPICAL WAVES... The axis of an Atlantic tropical wave is analyzed near 26W from 18N southward just west of the Cabo Verde Islands, moving W at 15 to 20 kt. A 1012 mb surface low is analyzed underneath the tropical wave near 08N26W. Showers and thunderstorms have decreased and become less organized during the past several hours in association with a tropical wave. Development, if any, should be slow to occur during the next couple of days while the wave moves westward. The axis of a second Atlantic tropical wave is analyzed near 46W from 03N to 19N, moving W at 15 to 20 kt. There is no significant convection noted with this tropical wave, however scattered moderate convection is evident west of the wave from 08N to 10N between 50W and 56W. The axis of a Caribbean tropical wave is near 70W from 17N southward to across western Venezuela and eastern Colombia, moving W at 10 to 15 kt. There is no significant convection noted over water with this tropical wave, however deep convection is occurring over the border of Venezuela and Colombia. The axis of an exiting Caribbean tropical wave is near 90W across Belize and Guatemala from 18N southward, moving W at 5 to 10 kt. Deep convection is occurring east of the wave axis from the SW Caribbean south of 13N and west of 76W, as well as in the NW Caribbean west of 83W, extending northwestward to the Yucatan Peninsula, including the east coast of Honduras and Nicaragua. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coast of Africa near Guinea- Bissau to 11N15W to 10N20W. The ITCZ continues from 10N20W to 09N25W, intercepting a tropical wave along 26W and continues to 07N29W to 06N41W. Scattered moderate convection is south of the monsoon trough to the Equator between the west coast of Africa to 20W. GULF OF MEXICO... A broad low pressure area of 1009 mb is nearly stationary and centered near 19N95W over the Bay of Campeche, accompanied by a surface trough extending from 22N98W near Tampico, Mexico through the low to 18N91W. Scattered moderate and isolated strong convection is noted mainly over southern Mexico, with scattered moderate convection in the Bay of Campeche south of 20N. Fresh to strong NW winds are noted northwest of the low, with gentle to moderate winds over the remainder of Bay of Campeche. Scattered to numerous showers and scattered thunderstorms are across the south-central Gulf south of 25N between 86W and 92W with moderate to fresh SE winds. Scattered showers and isolated thunderstorms associated with a mid-level trough are seen from the NE Gulf extending over central Florida. Light to gentle winds are noted by recent ASCAT data north of 25N. Seas are 3 ft or less across the basin, except locally 4 to 5 ft west of the trough. For the forecast, weak high pressure ridging over the central Gulf of Mexico will shift east through mid-week. Gradual development of a broad area of low pressure in the Bay of Campeche is possible during the next couple of days while it meanders near the coast of Mexico. The system should begin to move northward by midweek, and a tropical depression is likely to form late in the week when the low moves across the central or northwestern Gulf of Mexico. CARIBBEAN SEA... Refer to the tropical waves section above for information on any significant convection. Convergent ESE trade winds are triggering scattered showers and isolated thunderstorms near southeastern Cuba within 35 miles of 19N77W, and western Cuba between 22N and 23N from 80W to 83W. Moderate to fresh trades continue in the S central Caribbean, with gentle to moderate trades elsewhere. Seas of 3 to 5 ft prevail across the basin, except 5 to 7 ft in the S central Caribbean. For the forecast, a ridge of high pressure north of the basin combined with lower pressure over Central America and Colombia will support pulsing fresh to strong trades over the S central Caribbean and Gulf of Honduras through the upcoming weekend. Moderate to fresh trades will prevail elsewhere, except light to gentle south of 11N. ATLANTIC OCEAN... Refer to the Special Features section above for details on Tropical Storm Bill located well north of the discussion area. Scattered showers and thunderstorms extend across the SW N Atlantic west of 70W and north of 26N with fresh to strong SE winds with gusting to gale, based on the latest scatterometer imagery. Ridging dominates the basin, anchored by the Azores High north of the area near 35N35W. Moderate to fresh southerly return flow is noted north of 21N between 31W and 70W with fresh to strong trades south of 21N. Tightening pressure gradient between the high and lower pressure over Africa is causing fresh winds south of the Canary Islands from the west coast of Africa to 31W. Seas of 5 to 7 ft are present across the basin with 6 to 8 ft south of the Canary Islands. A large area of Saharan dust covers the tropical Atlantic westward to eastern Caribbean. Both the GOES Geocolor imagery and Sahara Dust imagery from CIMSS indicate this feature. For the forecast west of 65W, a ridge of high pressure across the area will continue to weaken today. Winds will be fresh to strong north of 28N through mid-week as a pair of cold fronts move by north of the area. $$ CM/PC