000 AXNT20 KNHC 161805 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 105 PM EST Fri Nov 16 2018 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 1200 UTC surface analysis and satellite imagery through 1745 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough axis extends from well over the interior of Africa to the coast of Sierra Leone near 08N12W and to 05N19W, where latest scatterometer data indicates that it transitions to the ITCZ axis, which continues to 03N28W to 03N38W and to 03N47W. Scattered moderate convection within 300 nm to the north of the monsoon trough between the coast of Africa and 19W. GULF OF MEXICO... In the upper levels, a strong jetstream branch originating from the eastern Pacific extends northeastward across the SW Gulf, to the Yucatan Peninsula and to across central Florida. At the surface, high pressure dominates the weather regime in the wake of the recent cold front passage. Cold air advection with the northerly flow around a 1025 mb high center located over the northwestern Gulf 27N94.5W is resulting in broken to overcast stratocumulus clouds across just about the entire sections of the eastern and middle Gulf. Broken to overcast low clouds associated with a surface trough are confined to the southwestern Gulf. Scattered showers are possible with these clouds. Clear skies are present generally to the north of 28N, and from 24N to 26N west of 92W. Isolated showers are over some areas of the Straits of Florida. A rather tight pressure gradient between the high pressure over the area and the recently departed cold front, now over the northwestern Caribbean Sea, is bringing mainly fresh northerly winds over the far southeastern Gulf and Straits of Florida. Gentle to moderate winds in anticyclonic fashion around the 1025 mb high are elsewhere across the Gulf. Little change is expected in the present synoptic pattern through Saturday, then the high pressure will begin to shift eastward on Sun in response to the next cold front that will be moving across Texas. This front is forecast to reach the Texas coast Sun night. CARIBBEAN SEA... The tail end of a cold front extends from central Cuba at 22N78W to near the Cayman Islands, where it becomes stationary to the coast of northeastern Honduras as of 15Z. Satellite imagery shows mainly broken low clouds, with possible scattered showers along and to the northwest of the front, with the exception of a pocket of multilayer clouds observed to the south of 19N between 83W and 86W. These clouds contain scattered showers and thunderstorms, which are being supported by a upper-level disturbance riding along a strong jet stream branch that northeastward from the eastern Pacific to across the northwestern Caribbean Sea and Yucatan Peninsula. The combination of strong northerly winds behind the front along with the availability of the low-level moisture being channeled from the Straits of Florida to western and central Cuba, has induced periods of heavy rain over some sections of mainly central Cuba since Thu evening. Periods of brief heavy rain along with localized flooding are possible over these same areas through the remainder of the afternoon. The strong northerly winds are forecast to diminish to fresh winds on Sat as the pressure gradient over the southeastern Gulf of Mexico and northwestern Caribbean slackens. A surface trough, the remnants of a former tropical wave, extends from northwest Colombia to just southwest of Jamaica. Isolated moderate convection is over NW Venezuela. Isolated showers moving quickly westward are seen from 13N to 19N between 74W and 79W. Scattered showers and isolated thunderstorms supported by low- level speed convergence, are over the far southwestern Caribbean south of 13N between 78W and the coast of Costa Rica. Patches of low-level moisture containing isolated showers are moving westward over the remainder of the Caribbean to the east of the cold front. The stationary front will gradually weaken through Sat night. High pressure over the central Atlantic will build southward through Sun bringing an increase to the trades across the eastern and central Caribbean that is expected to last into early next week. ATLANTIC OCEAN... A cold front, that is well defined in satellite imagery, is over the western Atlantic along a position from 32N72W to 25N77W and central Cuba as of 15Z. Scattered showers and isolated thunderstorms are along and within 60 nm east of the front north of 27N. Fresh to strong northerly winds are west of the front. Broken to overcast stratocumulus clouds, with isolated showers are noted within 60 to 90 nm west of the front, and scattered stratocumulus clouds are elsewhere west of the front. The front is forecast to become stationary from near 32N66W to the southeast Bahamas and eastern Cuba by Sat morning, and slowly weaken through Mon. A surface trough extends from near 27N74W to low pressure of 1012 mb near 24N75W and to just north of eastern Cuba. Scattered showers and thunderstorms are within 60 nm northeast and east of the low. Isolated showers and thunderstorms are elsewhere along and near the trough. The low is forecast to dissipate tonight or Sat along with the trough.. A cold front has dipped into the central Atlantic waters from 32N30W to 28N40W to 27N50w and dissipated to 29N57W. Another cold front has traversed the Canary Islands and extends from 32N10W to 26N15W. Scattered showers are along the coast of Morocco. For additional information please visit http://www.hurricanes.gov/marine $$ Aguirre