NHC Tropical Weather Discussion (Atlantic) National Hurricane Center - Tropical Weather Discussion (Atlantic)

  • NHC Atlantic Tropical Weather Discussion

    000 AXNT20 KNHC 141135 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 634 AM EST Fri Dec 14 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 0600 UTC surface analysis and satellite imagery through 1115 UTC. ...SPECIAL FEATURES... ...Gulf of Mexico Gale Warning... As of 0900 UTC, a cold front extends from the SE Louisiana coast near 29N90W to 27N90W to 21N94W to the coast of Mexico near 20.5N97W, and inland into Mexico. Gale force winds to 40 kt are occurring west of the front over the northwest and west-central Gulf of Mexico, and this was confirmed by an ASCAT pass from 0300 UTC. The front will reach from the Florida Big Bend to the Yucatan Channel tonight, and move SE of the basin on Sat. The gale force winds will continue through this afternoon west of the cold front, spreading southward through the west-central Gulf. Winds are forecast to be below gale force by this evening. Seas of 12 to 16 ft are expected to affect waters today from 22N-28N between 90W-97W. Please read the latest High Seas Forecast under AWIPS/WMO headers HSFAT2/FZNT02 KNHC for more details. ...Possible Gale off the coast of Morocco... Strong to near gale force winds with localized winds to gale force are expected today within 120 nm of the coast of Morocco between 30N-32N in Agadir, according to the latest forecast from Meteo France. These winds are being caused by a strong pressure gradient between a strong low over the western Mediterranean Sea and a 1030 mb high pressure to the west over the Atlantic near 32N18W. Winds will diminish by early Sat. ...MONSOON TROUGH/ITCZ... The ITCZ extends from the coast of Sierra Leone near 08N13W to 08N15W to 03N22W to 00N34W to the coast of Brazil near 02S43W. Scattered moderate convection is seen from 04N-09N between the W coast of Africa and 21W. Scattered showers are seen from 07N southward between 40W and the coast of South America. GULF OF MEXICO... A cold front and associated gale force winds in the west-central Gulf are described above in the Special Features section. A strong, deep-layered low pressure system is located over east Texas. CIRA Layered Precipitable Water imagery indicates that southerly flow east of the low is drawing a large amount of moist air northward from the western Caribbean into the NE Gulf of Mexico. Ahead of the cold front, over the northeastern Gulf of Mexico, numerous moderate and scattered strong convection is noted from 25N-30N between 82W-89W, including over the northern Florida Peninsula and eastern Florida Panhandle. The convection is being enhanced by strong upper-level divergence over the NE Gulf. Elsewhere N of 24N and E of 90W, scattered showers and isolated thunderstorms are seen. A few showers are also over the western Gulf behind the front. Widespread heavy shower and thunderstorm activity is expected to continue today in the NE Gulf ahead of the front. Strong wind gusts and locally enhanced seas are expected with the stronger thunderstorms. Winds and seas will diminish this weekend. CARIBBEAN SEA... Most of the Caribbean is relatively quiet with no significant features or convection at this time. However, the monsoon trough in the east Pacific, which is just south of Panama, is producing isolated thunderstorms in the extreme SW Caribbean south of 10N between 75W-81W. Elsewhere, some light trade wind showers are seen in the vicinity of Puerto Rico and Trinidad. Fresh to strong trade winds will prevail across the central Caribbean through the weekend, with highest winds near the coast of Colombia at night. A cold front will move through the Yucatan Channel later today, then stall and dissipate over the NW Caribbean this weekend. Strong north winds are forecast west of the front across the Gulf of Honduras late tonight and Sat. Large N swell will reach the Leewards on Sat, and spread south through the Atlantic passages during the weekend. ATLANTIC OCEAN... Scattered moderate convection is over the Atlantic east of Georgia and northern Florida north of 29N and west of 79W. This activity is from the same weather system that is producing widespread strong thunderstorms over the NE Gulf of Mexico and northern Florida. Elsewhere N of 28N and W of 78W, scattered showers and isolated thunderstorms are present. Expect strong thunderstorms to become widespread in this area later today. A cold front passes through 32N40W to 28N46W to 25N59W then transitions to a stationary front at that point to 24N63W, then transitions to a warm front at that point to 24N70W to 25N75W. Isolated showers are possible along the front. Farther to the southeast, a surface trough is analyzed from 27N43W to 17N47W. Broken clouds and isolated showers accompany the trough. The frontal boundary along 24N east of the Bahamas will drift northward today and slowly dissipate. Strong to near gale force southerly return flow will develop north of the Bahamas today ahead of a strong cold front that will sweep east across the northern waters during the weekend, reaching from Bermuda to northwest Cuba Sun night and from 31N71W to central Cuba on Mon. The front will then stall across the tropical waters north of the Antilles on Tue. For additional information please visit http://www.hurricanes.gov/marine $$ Hagen […]