SE Texas


For the North Atlantic, Caribbean Sea and the Gulf of Mexico:

Special Tropical Weather Outlook issued to discuss the potential for subtropical development over the central Atlantic.

Central Subtropical Atlantic: A large non-tropical area of low pressure located over the central subtropical Atlantic about 950 miles northeast of the northern Leeward Islands is producing an extensive area of disorganized showers and thunderstorms. Although this system may acquire some subtropical characteristics tonight and Thursday, it is unlikely to become completely detached from a frontal zone. By Friday, the low will move northeastward over cooler waters and interact with a mid-latitude trough, limiting the chance for additional subtropical or tropical development of the system. Additional information on this low, including warnings, can be found in High Seas Forecasts issued by the National Weather Service. The next Special Tropical Weather Outlook on this system will be issued by 9 AM EST Thursday, or earlier, if necessary. * Formation chance through 48 hours, medium, 40 percent. * Formation chance through 5 days, medium, 40 percent.

High Seas Forecasts issued by the National Weather Service can be found under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and online at

Posted 1 hour, 58 minutes ago by NHC Forecaster Forecaster Pasch

Special Features

Central Atlantic Storm Warning: A large, storm-force low pressure system is centered near 29N53W, or about 630 nm ESE of Bermuda. The central pressure is 981 mb. The maximum winds of 50-55 kt are located in the NW quadrant of the low pressure. The gales extend outward up to 520 nm from the center in the N semicircle, 240 nm SE quadrant and 320 nm SW quadrant. Winds of 25 kt or higher associated with the low are currently occurring north of 20N between 39W and 67W. Seas 12 ft or greater are occurring north of 22N between 43W and 67W. The low pressure is contributing toward 8 ft or greater seas everywhere north of 18N between 35W-73W. The estimated maximum seas of 35 ft are occurring in the NW quadrant near 30.5N 56W. The highest observed seas of 28 ft were measured from a drifting buoy near 28.8N 57.5W at 07/2140 UTC. An occluded front extends E from low pressure to a triple point near 30N43W. A cold front extends SE from the triple point to 25N37W. A warm front extends ESE from the triple point to 28N36W. Scattered moderate convection is noted north of 24N between 33W and 53W.

The low is forecast to move ENE over the next 24 hr, then NE, reaching a position of 31N45.5W Thu evening, 34N41W Fri morning, and 38N39W Fri evening. Winds over our area south of 31N are forecast to diminish below storm force late tonight or early Thu morning. However, gales will continue through Fri, then diminish below gale force Fri night as the low pressure moves farther away from the area. Seas of 12 ft or greater, primarily in swell, will reach as far west of 74W Thu night into Fri, and as far south as 15N Fri across the tropical Atlantic. Swell of 8 ft or greater will reach as far west as 80W and as far south as 03N. The swell will pass through the NE Caribbean passages tonight through Sat. Seas will subside to below 20 ft by Sat night over the north- central Atlantic, but remain over 12 ft into early next week.

Environmental conditions appear marginally conducive for development, and a subtropical or tropical storm could form within the next day or so. By Friday, the low will move northeastward over cooler waters and interact with a mid-latitude trough, limiting the chance for additional subtropical or tropical development of the system. Regardless of whether or not this system is classified as a tropical/subtropical cyclone, the impacts across the area will remain the same.

More information about this system, including the associated storm warning, can be found in the High Seas Forecasts issued by the National Hurricane Center at and the Offshore Zone Forecasts at

Monsoon Trough/ITCZ

The monsoon trough extends from the coast of Guinea-Bissau near 11N15W to 07N17.5W. The ITCZ continues from 07N17.5W to 06N21W to 06N47W. Scattered moderate and isolated strong convection is noted from 02N-08N between 21W-42W.

Gulf Of Mexico

A 1027 mb surface high pressure is centered over N Florida with gentle to moderate winds prevailing across the Gulf. Seas are 1-3 ft over the NE half of the Gulf and 4-5 ft over the SW half. Patchy dense fog is present within 20 NM of the coast from the Florida Panhandle to Beaumont, Texas. Periods of dense marine fog are likely to continue across portions of the N Gulf Coast between Apalachicola, FL and Galveston, TX through the next couple of days.

For the forecast, high pressure centered over northern Florida will meander about the area through the forecast period. Moderate to fresh return flow will prevail W of 92W through tonight, then diminish to gentle to moderate breezes through Mon night.

Caribbean Sea

The pressure gradient between the high pressure over NE Florida and lower pressure over N South America is contributing toward fresh NE winds in the central and western Caribbean Sea. In the E Caribbean, gentle N winds are present. Seas in the central and W Caribbean are 5-7 ft and seas in the E Caribbean 3-4 ft except 5-7 ft of N swell through the Mona and Anegada Passages. Scattered moderate convection is noted just offshore the coast of Costa Rica.

For the forecast, a strong low pressure system currently over the central Atlantic will continue to deepen during the next few days, maintaining NE-E winds across much of the forecast waters. Fresh to pulsing strong NE winds will affect the Caribbean Passages, the lees of the Greater Antilles, and offshore Colombia into Fri. Large NE swell across the central Atlantic will move through the Caribbean Passages and Tropical Atlantic waters into the weekend, with highest seas tonight into Sat.

Atlantic Ocean

Please read the Special Features section above for details on a storm force low pressure system, affecting the waters north of 20N between 37W and 73W.

Elsewhere, a weak pressure pattern prevails off central and northern Florida, with winds gentle or weaker NW of a line from 31N73W to West Palm Beach, FL. Fresh NE winds prevail south of 26N and west of 73W. Seas are less than 8 ft west of 73W.

A surface trough extends over the tropical Atlantic from 09N57W to 14N50W. Scattered moderate convection is noted from 08.5N to 15N between 45W and 59W. A 1014 mb high pressure is analyzed near 19N32W. A cold front extends from 31N14W to the westernmost Canary Islands to 25N25W, then continues as a stationary front to 25N30W to 28N36W. Scattered moderate convection is noted from 26N-31N between 16W-30W. Seas over 8 ft prevail behind the cold front, N of 27.5N between 15W-30W.

For the forecast for areas W of 55W, large long-period north to northeast swell will impact the Atlantic waters and Caribbean Passages between the southeastern Bahamas and the E Caribbean producing high seas into the weekend, with large E swell reaching the Florida offshore waters N of 26N early Fri through Sat, due to the low pressure mentioned above in the special features section.

Posted 3 hours ago by NHC Forecaster Hagen