AXNT20 KNHC 142346

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
645 PM 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 1800 UTC surface analysis and satellite imagery through 2330 UTC.


...Gulf of Mexico Gale Warning...

A cold front extends across the Gulf of Mexico from 30N87W to 21N89W, then continues across Mexico. Latest scatterometer data depicts gale force winds already occurring from 23N-26N and west of 95W. Seas of 12 to 16 ft are expected to affect waters today from 22N-28N between 90W-97W. The front will reach from the Florida Big Bend to the Yucatan Channel overnight, and continue east passing through the Bahama Channel on Sat night. Strong to near gale-force southerly flow and scattered thunderstorms will precede the front across the eastern Gulf of Mexico. 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 34N12W. Winds will diminish by early Saturday. Please refer to the Meteo-France High Seas Forecast that is listed on the website: www.meteofrance.com/ previsions-meteo-marine/bulletin/grandlarge/ metarea2 for more details.


The monsoon trough remains inland in Africa. The ITCZ passes through the coastal sections of Sierra Leone near 08N12W to 09N21W. A surface trough is along 24W from 02N-09N. The ITCZ continues from 02N26W to 00N39W. Scattered showers are noted south of the ITCZ to 03N between 12W-22W.


A cold front extends across the basin from 30N87W to 21N89W, then continues across Mexico. A surface trough is analyzed behind the front from 30N89W to 22N95W. Gale-force winds are noted in scatterometer data across the western Gulf waters. Refer to the section above for details about the Gale Warning in effect. A shear line has developed this afternoon east of the front from 29N83W to 25N85W affecting the Florida Peninsula. Moderate to fresh winds prevail across the basin.

The current cold front will reach the Port of Tampa to Yucatan Channel this evening, and continue eastward passing through the Bahama Channel on Saturday night. Strong to near-gale force southerly wind flow, and scattered thunderstorms, will continue preceding the front across the eastern Gulf of Mexico. Strong to near-gale force northwesterly wind flow will continue west of the front through sunrise on Saturday. Moderate west flow is expected on Saturday evening as the seas will subside. Light northerly winds are forecast on Monday. Moderate return flow will set up across the northwest waters on Tuesday, with broad low pressure developing in the SW corner of the Gulf of Mexico.


Most of the Caribbean is relatively quiet with no significant features or convection at this time. Some light trade wind showers are seen in the vicinity of Puerto Rico and the Lesser Antilles. Another area of scattered showers is noted along 84W, affecting portions of Nicaragua and Honduras.

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 tonight, then stall and dissipate over the northwest Caribbean this weekend. Strong north winds are forecast west of the front across the Gulf of Honduras on Saturday. Large north swell will reach the Leewards on Saturday, and spread south through the Atlantic passages during the weekend.


Scattered moderate convection continues over the west Atlantic mainly west of 79W. This activity is from the same weather system that is producing widespread strong thunderstorms over the northeast Gulf of Mexico and northern Florida. Expect strong thunderstorms to become widespread in this area overnight as a cold front approaches from the west.

To the east, a cold front passes through 31N36W to 25N57W, then transitions to a warm front at that point to 27N77W. Isolated showers are possible along the cold front. Farther to the southeast, a surface trough is analyzed from 25N45W to 17N48W. No significant convection is related to this trough at this time.

Strong to near gale force southerly return flow will continue north of the Bahamas tonight ahead of a cold front that will sweep east across the northern waters during the weekend, reaching from Bermuda to northwest Cuba Sunday night and from 31N71W to central Cuba on Monday. The front will then stall across the tropical waters north of the Antilles by Tuesday.

For additional information please visit http://www.hurricanes.gov/marine