886 AXNT20 KNHC 301059 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Mon May 30 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 1045 UTC. ...TROPICAL WAVES... An eastern Atlantic tropical wave has its axis along 36W from 02N to 14N, moving westward around 15 kt. Increasing scattered moderate to isolated strong convection is noted where the wave interrupts the ITCZ from 03N to 08N between 33W-36W. A central Atlantic tropical wave has its axis along 60W from 02N to 14N, moving westward at 13 kt. Isolated showers are possible near the wave. ...MONSOON TROUGH/ITCZ... The monsoon trough reaches the Atlantic through the coast of Guinea-Bissau near 11N16W and extends to 09N17W, where overnight scatterometer data indicates that it transitions to the ITCZ and continues to 06N33W. It resumes to the west of the eastern Atlantic tropical from 05N36W to 03N43W and to 00N50W. Aside from convection associated to the eastern Atlantic tropical wave, numerous moderate to isolated strong convection is emerging off Africa within 180 nm south of the trough between 14W-16W. Similar activity is within 120 nm south of the ITCZ between 24W- 29W, and within 60 nm either side of the ITCZ between 36W- 41W. Scattered moderate convection is within 60 nm north of the ITCZ between 41W- 45W. ...GULF OF MEXICO... Abundant rich deep tropical mid to upper-level moisture in the form of broken to overcast multilayer clouds is streaming eastward from the eastern Pacific Ocean to across the southern sections of the Gulf. This moisture coupled with diffluent flow aloft along with instability initiated by an upper-level low, and a rather pronounced jet stream that runs along the southern part of the upper-level low are all combining with a couple of surface troughs leading to scattered to numerous showers and thunderstorms over the southeastern Gulf. One of the troughs extends from near 27N86W to 24N89W, while the other one extends from near 23N91W to 19N93W. Scattered showers and isolated thunderstorms are over the Bay of Campeche. Isolated showers and thunderstorms are over the west- central Gulf from 22N to 26N west of 94W. The weather pattern over the remainder of the Gulf is being influenced by the western periphery of Atlantic high pressure that reaches the central Gulf. The pressure gradient between this feature and lower pressure over Mexico is supporting moderate to locally fresh southeast winds across the western Gulf waters, especially to the west of 93W. A light to gentle anticyclonic wind flow is present elsewhere. Seas of 3-5 ft are present in the western, south- central and southeastern Gulf, seas of 4-6 ft are in the southwestern and NW Gulf, while lower seas of 1-3 ft seas are in the remainder of the basin. For the forecast, high pressure extending from the western Atlantic to across the central Gulf will maintain moderate to fresh SE winds over the western Gulf and mainly gentle SE winds elsewhere through the period. Winds may increase to locally strong off the Texas coast tonight. A large area of low pressure may impact the southern Gulf by around mid-week. ...CARIBBEAN SEA... Abundant rich tropical moisture covers the western section of the Caribbean. This moisture is being transported from the eastern Pacific Ocean via a rather strong upper subtropical jet stream branch that stretches eastward to far northwestern Caribbean. Resultant atmospheric instability in this part of the basin is resulting scattered showers and thunderstorms mainly from 16N to 19N west of 83W, and south of 16N west of 81W to just inland Nicaragua and northern Costa Rica. Similar convection is just inland and along the coast of northwestern Colombia. Fairly tranquil weather conditions are found in the rest of the Caribbean Sea, with the exception of a pocket of scattered showers and thunderstorms that is located from along the southwest part of Haiti, south to 15N and between 71W-74W. The pressure gradient between subtropical high pressure and lower pressure over Colombia is producing fresh to strong trades across the central Caribbean and Gulf of Honduras, with the strongest winds occurring offshore Colombia and the Gulf of Venezuela. Moderate to locally fresh trades are noted in the eastern Caribbean, while lighter winds are present over the northwestern southwestern Caribbean as detected by overnight ASCAT data. Seas are 5-8 ft in the central basin, except for slighter higher seas of 6-9 ft in the Colombian basin and 3-5 ft elsewhere, except for 4-6 ft seas south of 15N between 64W-68W. For the forecast, the subtropical ridge north of the area will support fresh to strong winds and seas to 8 ft off the coasts of Colombia and Venezuela into mid-week. Moderate to fresh trades will prevail across much of the remainder of the Caribbean into mid- week. A large area of low pressure may form in the far NW Caribbean late this week. ...ATLANTIC OCEAN... Divergence aloft provided by an upper-level trough that extends from offshore the southeastern U.S. to an upper-level low just off the northeast Florida coast and to another one over the eastern Gulf of Mexico support a surface trough off Florida is helping to sustain scattered to numerous shower and thunderstorm activity that covers most of the waters west of about 72W, including the Bahamas, Florida and surrounding waters. Colder air aloft along with favorable dynamics in play may allow for some of the shower and thunderstorm activity to attain strong to possibly severe status. Mariners should exercise caution while navigating these waters today and into this evening as showers and thunderstorms may be accompanied by strong winds and frequent lightning. The subtropical high over the central Atlantic dominates the rest of the tropical Atlantic, permitting fairly tranquil weather conditions. Overnight ASCAT data highlighted moderate to fresh trades off northern Hispaniola and the southeastern Bahamas, including the entrance of the Windward Passage. Seas of 3-6 ft are noted W of 55W. Farther east, a cold front enters the basin near 31N17W and continues southwestward to 23N29W, where it transitions into a stationary front that reaches to near 22N42W. No deep convection is present near this frontal boundary. Isolated shower and/or small patches of light rain are possible along and near this frontal boundary. Another cold front has just entered the area from near 31N27W to 29N33W. It continues northwestward to 32N39W. Fresh northwest winds follow this front, along with seas of 8-9 ft due to a north swell that follows the front west of 30W, but exceeds the front out to within 180 nm east of 30W. Farther south, moderate to fresh trades are over the waters south of 20N and between 35W and the Lesser Antilles. The combination of wind generated wave mixed with northeast to east swell is generating seas of 5-7 ft over these waters. Winds are in the gentle to moderate range along with 3-6 ft seas across the remainder of the basin. For the forecast west of 55W, the subtropical ridge will change little over the western Atlantic through the next few days. A weak trough is expected to form near the NW and central Bahamas by mid-week, then lift northeastward Thu and Thu night. Winds will pulse moderate to fresh north of Hispaniola and the southern Bahamas into Tue. Gentle to moderate winds will continue over the remainder of the region into mid-week. Active weather is expected over most of the western half of the forecast waters through the next few days. $$ Aguirre