000 AXNT20 KNHC 142341 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 805 PM EDT Apr 14 2020 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 32N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 1800 UTC surface analysis and satellite imagery through 2330 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough axis extends from the coast of Africa over Guinea near 10N14W to 05N19W, where latest scatterometer data indicates that it transitions to the ITCZ and continues to the equator at 28W and to the coast of Brazil near 03S40W. Scattered moderate convection is within 180 nm south of the trough between 15W-18W and within 120 nm north of the ITCZ and between 20W-23W. GULF OF MEXICO... A stationary front is draped in a northeast to southwest fashion from Apalachicola, Florida southwestward to 2692W and to inland northeastern Mexico. A pre-frontal trough extends from northeast Florida southwest to near 27N86W. Abundant atmospheric instability in the area of this front has helped trigger off scattered showers and thunderstorms across most of the NE Gulf. Isolated showers are possible elsewhere near the front. Expect for the shower and thunderstorm activity to remain active through Wed as the front begins to push southward as a cold front. A tight gradient between the front and high pressure building southward over Texas is allowing for fresh to strong winds to exist north of this front in the NW Gulf along with wave heights to 8 ft. Latest Ascat data shows mainly moderate north to northeast winds elsewhere northwest of the front, with wave heights of 5-7 ft, while light to gentle southerly winds are noted south of the front. In the SW Gulf, low pressure of 1012 mb is identified to be near 21N95W. The low was nicely depicted by the latest Ascat pass over that part of the Gulf. In addition, buoy 42055 at 22N94W is reporting light south winds and latest visible satellite imagery shows low-level clouds rotating cyclonically near and around this low. The forecast calls for the above described stationary front to begin to push southward as a cold front on Wed as high pressure builds southward in its wake ushering in a drier and cooler air mass. The front is forecast to become stationary over the south- central Gulf late Thu and lift back to the north as a warm front Fri. Fresh to strong northerly winds and building wave heights are expected in behind the front through Thu. Another cold front is expected to move over the northern Gulf by Fri night, then become stationary and lift northward as a warm front by late Sat. Smoke from agricultural fires in southern Mexico and Honduras will continue to reduce visibility, at times, over the south- central Gulf through at least the next few days. CARIBBEAN SEA... A surface ridge extends from strong central Atlantic high, that is well north of the area, southwestward to the northwest Caribbean. The associated gradient is allowing for generally gentle to moderate easterly winds across the basin, except in the south-central Caribbean section and near the coast of Colombia where pulses of fresh to strong northeast winds will continue through Thu. Latest buoy and satellite altimeter data passes show wave heights in the range of 4-6 ft throughout the basin except for higher wave heights peaking to 8 ft in the Gulf of Honduras where persistent east winds are in the fresh to locally strong range. No significant thunderstorm activity is noted over the Caribbean at this time as very dry aloft maintains rather stable and dry conditions throughout. The only exception is that of quick moving isolated showers as observed on regional radar over the Leeward and Virgin Islands as well as over the interior of Puerto Rico and its surrounding waters. The forecast calls for the gradient associated with the central Atlantic ridge to maintain fresh to strong winds near and along the coast of Colombia and Honduras through Thu. Winds and seas over much of the basin will diminish through the end of the week as the Atlantic weakens and shifts eastward. Smoke from inland agricultural fires, as noted in the GOES-R visible imagery, may limit visibility, at times, off the Yucatan Peninsula and the offshore waters of Belize and Honduras possibly into Fri. ATLANTIC OCEAN... The 18Z analysis has a surface ridge extending from a 1031 mb central Atlantic high center, that is located well north of the area near 37N48W, southwestward from this high to Bermuda, then to the northwestern Bahamas and to South Florida. A stationary front is draped northeast to southwest inland over inland Georgia. A series of upper-level shortwave troughs are quickly moving from west to east over the southeastern U.S. while at the same time plenty of upper-level moisture, as noted in water vapor imagery, is streaming eastward via a strong jet stream remains evident over and near this boundary. These ingredients have come together, with the end result being the development of scattered shower and isolated thunderstorm activity over the northwest part of the area north of 29N and west of 70W. Some of this activity may produce gusty winds and rough seas as it is expected to last through at least Wed. Latest satellite data indicates the highest frequency of lightning to be north of 30N and between 74W-78W. A recent Ascat pass revealed moderate to fresh southerly winds north of about 27N and west of 74W, where wave heights are 4-6 ft. Farther east, a cold front is along a position from near 32N34W to 27N41W, where it becomes stationary to 22N57W. A sharp upper- level trough is over the cold/stationary front. Upper-level divergence east of this trough is helping to support areas of rain with possible embedded scattered showers along the cold front, east to a line from 32N26N to near 27N39W and within 60 nm north and of the cold and stationary fronts. Isolated showers moving quickly westward in fast east flow are elsewhere near the stationary front. The gradient between this boundary and the strong high pressure center north of the area is resulting in fresh to strong northeast winds along with wave heights in the range of 8-10 ft over an area that is bounded from 27N to 32N and between 42W-55W. These conditions are forecast to improve by early Wed as the front weakens. The forecast calls for the aforementioned stationary front to begin to push southeastward as a cold front on Wed, reach a position from near 32N71W to South Florida by early Thu, then from near 28N65W to the Straits of Florida by Thu night. The front is then expected to become stationary near 25N on Fri, and lift back to the north as a warm front while weakening through Fri night. Fresh to strong northerly winds are expected behind this front on Thu. A surface ridge will develop northeast of the warm front on Fri near 33N. Models suggest that the ridge will be forced southward this weekend in response to a cold front that will move off the southeastern U.S. coast this weekend and across the far northern waters through late Sun. Scattered showers and isolated thunderstorms are possible with this front. $$ Aguirre