Southwestern Caribbean Sea: Disorganized showers and thunderstorms over the southwestern Caribbean Sea are associated with a broad area of low pressure. Gradual development of this system is expected over the next several days, and a tropical depression is likely to form by early next week while the system moves generally northward to northwestward over the central and western Caribbean Sea. Regardless of development, locally heavy rains are possible over portions of the adjacent land areas of the western Caribbean during the next few days, including Jamaica, Hispaniola, and Cuba. * Formation chance through 48 hours, medium, 50 percent. * Formation chance through 7 days, high, 80 percent.

Near the Greater Antilles: A trough of low pressure extending from near Puerto Rico eastward over the adjacent waters of the Atlantic is producing a large area of showers and thunderstorms near and over portions of the Greater Antilles and the Leeward Islands. Slow development is possible during the next couple of days while the system moves west-northwestward near the Greater Antilles. Then, this system is expected to be absorbed into the low pressure area over the Caribbean Sea. Regardless of development, locally heavy rains are possible during the next few days from the northern Leeward Islands westward across Puerto Rico and Hispaniola to eastern Cuba and the southeastern Bahamas. For more information on this system, including gale warnings, see High Seas Forecasts issued by the National Weather Service. * Formation chance through 48 hours, low, 10 percent. * Formation chance through 7 days, low, 10 percent.

North Atlantic (AL96): Showers and thunderstorms continue to show signs of organization near a low pressure system centered a few hundred miles west-northwest of the Azores. Environmental conditions could allow for additional development today and tonight, and the system could become a short-lived subtropical or tropical storm while it moves east-southeastward at 10 to 15 mph. Upper-level winds are forecast to become unfavorable for further development by late this weekend. Interests in the Azores should monitor the progress of this system. For more information, including gale warnings, see High Seas Forecasts issued by the National Weather Service and Meteo France. * Formation chance through 48 hours, medium, 60 percent. * Formation chance through 7 days, medium, 60 percent.

High Seas Forecasts issued by the National Weather Service can be found under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and online at ocean.weather.gov/shtml/NFDHSFAT1.php

High Seas Forecasts issued by Meteo France can be found under WMO header FQNT50 LFPW and available on the web at www.meteofrance.com/previsions-meteo-marine/bulletin/grandlarge/ metarea2

Posted 14 minutes ago by NHC Forecaster Forecaster Reinhart

Tropics Watch Satellite

Special Features

The Southwestern Caribbean Sea

A 1007 mb low pressure center is near 12N81W. The monsoon trough is along 11N/12N from 74W in Colombia westward. Gradual development of this system is expected during the next several days. It is likely for a tropical depression to form by early next week. The forecast movement is generally northward to northwestward in the the central and western sections of the Caribbean Sea. Locally heavy rains are possible in parts of the adjacent land areas of the western Caribbean Sea during the next few days, including Jamaica, Hispaniola, and Cuba. The chance for this feature to develop into a tropical cyclone during the next 48 hours or so is medium.

The Atlantic Ocean Gale-Force Wind Warning

Expect for the next 6 hours or so: easterly gale-force winds, and rough to very rough seas, from 21N to 23N between 59W and 64W. Expect strong to near gale-force NE to E winds, and rough to very rough seas, elsewhere from 15N northward between 40W and 74W. Expect winds 20 knots or less, and rough to very rough seas in N to NE swell with the highest seas from 27N northward from 50W eastward, in the remainder of the Atlantic Ocean from 14N northward between 35W and 79W. These seas will last through the weekend before subsiding gradually early next week. A surface trough with abundant deep tropical moisture will generate scattered to numerous convective precipitation, that may produce heavy rainfall through the weekend, from the Virgin Islands westward to parts of the Greater Antilles. It is possible that the rainfall may lead to flash floods and potential landslides in these islands through the weekend.

Moderate seas are in the remainder of the Atlantic Ocean. Strong or faster NE winds are in the remainder of the area that is from the shear line to 23N45W 25N53W 28N64W 28N75W between 42W and the Bahamas. Moderate to fresh winds are in much of the remainder of the rest of the Atlantic Ocean.

Please, refer to the latest NWS High Seas Forecast, that is issued by the National Hurricane Center, at the website https//www.nhc.noaa.gov/text/MIAHSFAT2.shtml, and the weather bulletins that are issued by your local weather bureau office for more details.

A stationary front is along 31N28W 23N35W 21N42W. A shear line continues from 21N42W, to 18N50W 19N60W 19N67W. A separate surface trough is along 19N43W 16N45W 13N46W. Rough to very rough seas are from the stationary front/shear line northward, and in the waters that are bounded by a 28N68W 29N74W line and a 19N69W 25N76W line, from Hispaniola and the Bahamas northward. Precipitation: numerous strong is from 18N to 21N between 52W and 61W. Widely scattered moderate to isolated strong is in the remainder of the area that is from 15N to 23N between 50W and 72W. Widely scattered moderate to isolated strong is from 26N northward between 23W and 31W. A 1026 mb high pressure center is near 33N61W. Broad surface anticyclonic wind flow is from the stationary front/the shear line westward and northwestward. A 1019 mb high pressure center is near 28N20W. Broad surface anticyclonic wind flow is from 20N northward from the frontal boundary eastward.

Tropical Waves

An Atlantic Ocean tropical wave is along 36W/37W, from 14N southward, moving westward 10 knots to 15 knots. The monsoon trough is along 07N between 24W and 38W. Precipitation: widely scattered to scattered moderate, and isolated to widely scattered strong, are from 02N to 12N between 10W and 43W.

An Atlantic Ocean tropical wave is along 59W/60W, from 15N southward, moving westward 10 knots. Convective precipitation is about 180 nm to the north of the northern end of the tropical wave. This precipitation is close to: the shear line, and it is to the east of upper level cyclonic wind flow that is surrounding Hispaniola. Precipitation: widely scattered moderate to isolated strong is between 60W and 72W.

Monsoon Trough/ITCZ

The monsoon trough passes through the coastal plains of Guinea close to 10N14W, to 08N20W 07N32W 07N38W. An Atlantic Ocean tropical wave is along 36W/37W. Precipitation: widely scattered to scattered moderate, and isolated to widely scattered strong, are from 02N to 12N between 10W and 43W.

Gulf Of Mexico

A NW-to-SE oriented surface trough is along 20N96W, through the Isthmus of Tehuantepec of southern Mexico, through northern Guatemala, through the northernmost sections of Nicaragua, to 14N82W in the NW Caribbean Sea. Precipitation: isolated moderate to locally strong is from 22N southward from 90W westward.

A second surface trough, from N-to-S, is along 91W/92W, from 27N to the coast of Louisiana. Precipitation: isolated moderate is from 25N northward from 90W westward.

Moderate to slight seas cover the entire area in general. An exception is for moderate to near-rough seas in the Straits of Florida. Strong NE winds are from 27N southward from 88W eastward. Broad fresh to moderate anticyclonic wind flow spans the rest of the Gulf of Mexico.

A broad high pressure ridge extends from the western Atlantic into the SE U.S. The pressure gradient between this ridge and a trough across southern Mexico and the northern portion of Central America will support moderate to fresh winds and moderate seas across most of the Gulf region through the upcoming weekend. Fresh to strong E winds and higher seas are expected in the southeastern Gulf, including the Straits of Florida, through tonight, then mostly in the Straits of Florida through the upcoming weekend. Winds across the basin will begin to veer SE early Sun into early next week as a cold front slowly approaches E Texas.

Caribbean Sea

A trough of low pressure, that extends from near Puerto Rico eastward to the adjacent waters of the Atlantic Ocean, is producing a large area of showers and thunderstorms near and in parts of the Greater Antilles and the Leeward Islands. Slow development is possible during the next couple of days. The forecast movement is west-northwestward near the Greater Antilles. This system is expected to be absorbed into the Caribbean Sea low pressure area. Locally heavy rains are possible during the next few days, from the northern Leeward Islands westward, to Puerto Rico and Hispaniola, to eastern Cuba, and to the southeastern Bahamas. Please, refer to the latest NWS High Seas Forecast, that is issued by the National Hurricane Center, at the website https//www.nhc.noaa.gov/text/MIAHSFAT2.shtml, and the weather bulletins that are issued by your local weather bureau office for more details.

Moderate to slight seas cover the entire area. Fresh NE winds are in the NW corner of the area. Moderate NE winds are elsewhere from 14N northward from Jamaica westward. Strong NE winds are in the Windward Passage. Moderate NE winds are from 15N to Hispaniola. Moderate or slower winds are in the remainder of the Caribbean Sea.

The 24-hour rainfall totals in inches, for the period that ended at 02/0000 UTC, are: 0.57 in Curacao; and 0.03 in Guadeloupe. This information is from the Pan American Temperature and Precipitation Tables/MIATPTPAN.

The pressure gradient between a high pressure ridge N of the area and lower pressure over the SW Caribbean will support fresh to strong NE to E winds in the lee of Cuba, the Windward Passage, and south of Hispaniola, including the Mona Passage, into the upcoming weekend. Large N to NE long period swell over the NE Caribbean passages will subside late on Sat. A broad area of low pressure is forming over the southwestern Caribbean. Additional gradual development is possible over the next several days, and a tropical depression is likely to form late this weekend or early next week while the system drifts generally northward or northwestward over the central or western Caribbean Sea. There is a medium chance for tropical cyclone development in the next 48 hours, and a high chance of development in the next 7 days. Active weather will impact the majority of the basin into the weekend with locally heavy rains possible over portions of the western and central Caribbean associated with the area of low pressure interacting with an upper level trough lingering across the north central basin.

Atlantic Ocean

Please, read the SPECIAL FEATURES section, for details about the stationary front, the shear line, and the gale-force winds/rough to very rough seas, for the Atlantic Ocean.

A broad high pressure ridge extends across the western Atlantic along about 33N. The pressure gradient between this area of high pressure and low pressure over the SW Caribbean will support strong easterly winds and rough to very rough seas over the Western Atlantic S of 25N, from 55W through the Straits of Florida over the next few days, gradually shifting westward Sat through Tue. Peak seas of 12 to 15 ft are expected E of the Bahamas through Tue, subsiding into the middle of next week. Peak winds reaching minimal gale-force between 55W and 65W this evening will diminish to near gale force by Sat morning. The area of strong to near- gale winds will gradually shift westward to the SE Bahamas through Sun, then shift northward across the NW zones early next week. Very active weather should be expected across these waters E of 70W through Sun.

Posted 9 minutes ago by NHC Forecaster Mt/Al

Tropics Watch Sea Temperature