000 AXNT20 KNHC 152335 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Wed Jun 16 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. Based on 1800 UTC surface analysis and satellite imagery through 2300 UTC. ...SPECIAL FEATURES... Tropical Storm Bill is centered near 41.6N 59.6W at 15/2100 UTC or 250 nm SE of Halifax Nova Scotia moving NE at 31 kt. Estimated minimum central pressure is 998 mb. Maximum sustained wind speed is 50 kt with gusts to 60 kt. Bill is well on its way to becoming an extratropical cyclone. It is forecast to become a post-tropical low by this evening, and dissipate on Wed. 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 to 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 and 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... A tropical wave is analyzed near 27W from 18N southward just west of the Cabo Verde Islands, moving W at 15 to 20 kt. Shower activity is limited in association with this wave. Only a few showers are noted where the wave meets the ITCZ. Development, if any, should be slow to occur during the next couple of days while the wave moves westward. Thereafter, a combination of dry air aloft and strong upper-level winds should end the chances of formation when the wave reaches the central tropical Atlantic. A second tropical wave is along 48W from 03N to 19N, moving W at 15 to 20 kt. Scattered showers are near the wave axis. A tropical wave is moving across the central Caribbean with axis along 72W from 17N southward to across western Venezuela and eastern Colombia, moving W at 10 to 15 kt. The wave is likely enhancing some convective activity over western Venezuela and eastern Colombia. A tropical wave crosses Guatemala and combined with the broad area of low pressure over the Bay of Campeche will continue to support showers and thunderstorms across northern central America. Please, see the Special Features section for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coast of Africa near Guinea- Bissau to 11N20W. The ITCZ continues from 11N20W to 07N30W to 05N40W. Scattered moderate convection is from 02N to 10N E of 16W to the coast of Africa. GULF OF MEXICO... A broad low pressure is over the Bay of Campeche. Please, see the Special Features section for more details. A weak ridge dominates the remainder of the Gulf waters. Mainly light to gentle winds and seas of 1-3 ft prevail across the northern half of the Gulf, with gentle to moderate winds in the Bay of Campeche and NW of the Yucatan Peninsula where some convective activity is noted. An area of fresh to strong NW winds are observed on the west side of the low pressure and near the Veracruz region. Seas over the southern half of the Gulf are in the 2-3 ft range with the exception of 4-6 ft in the Bay of Campeche. A band of scattered to numerous showers and thunderstorms are along the northern Gulf coast from northern Florida to the upper Texas coast. Convective activity is also noted over parts of the Yucatan peninsula, SE Mexico and the Bay of Campeche. For the forecast, gradual development of a broad area of low pressure in the Bay of Campeche is possible while it meanders near the coast of Mexico. This system may bring an increase in winds and seas across the Gulf waters toward the end of the work-week as it is forecast to become a tropical depression. CARIBBEAN SEA... A tropical wave is moving across the central Caribbean. Refer to the tropical waves section above for details. The most recent scatterometer data provide observations of fresh to locally strong trades over the south-central Caribbean and mainly moderate winds elsewhere, except S of 11N where light and variable winds area noted. Seas are generally in the 4 to 6 ft range, except in the lee of Cuba, Windward Passage and near the coast of Honduras and Nicaragua. Showers and thunderstorms have developed over most of Cuba and northern Central America under a diffluent pattern aloft. For the forecast, a ridge 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. A pair of tropical waves are moving westward between the west coast of Africa and the Lesser Antilles. Refer to the tropical waves section above for details. A ridge dominate the entire Atlantic forecast area anchored by the Bermuda-Azores High located north of the area near 35N35W. The ridge extends across the Bahama, Cuba and southern Florida into the Gulf of Mexico. Moderate to fresh southerly flow is noted on the western periphery of the ridge and mainly N of 27N between 70W-80W. Scattered showers and thunderstorms are over much of Florida and also N of 27N between 70W-77W. Strong SW flow ahead of an upper-level trough over the eastern CONUS is helping to induce this convective activity. An upper-level low is also producing some shower activity over the central Atlantic from 20N-26N between 40W-47W. Moderate to fresh trades are seen E of the Lesser Antilles with seas of 6-7 ft. For the forecast west of 65W, 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. Farther E, tightening pressure gradient between the Bermuda- Azores high and lower pressure over Africa is causing fresh N-NE winds from 15N-25N E of 30W to the coast of W Africa. seas of 7-8 ft are within these winds. $$ GR