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Tropical Weather Discussion NWS National Hurricane Center Miami FL 0615 UTC Tue Dec 16 2025 Tropical Weather Discussion for North America, Central America Gulf of America, Caribbean Sea, northern sections of South America, and Atlantic Ocean to the African coast from the Equator to 31N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0000 UTC surface analysis and satellite imagery through 0437 UTC. ...SPECIAL FEATURES... Western Atlantic Significant Swell Event: A cold front extends from near 31N62W to the central Bahamas and to the southern Straits of Florida. Strong high pressure is building in behind the front. Gale-force winds that were over the waters N of 30N and W of the front to 73W have diminished below gale-force while gale- force winds persist N of 31N. This system and the associated winds continue to support large, northerly swells of 12-17 ft W of the front and higher N of 31N with wave periods of 8-11 seconds. The large northerly swell will reach the islands of the northeast Caribbean late Tue night into early Wed as it merges with easterly trade wind swell moving through the regional waters. Seas will begin to gradually subside from NW to SE during the middle of the week. Please read the latest High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more information. East Atlantic Significant Swell Event: Large, long-period north to northeast swell mixed with northwest swell continues to affect most of the eastern tropical and subtropical Atlantic. Seas of 12 ft or greater are currently from 05N to 24N between 27W and 51W, peaking around 13 ft per recent satellite altimeter data. Global wave models show northerly swell of 14 to 16 seconds mixing with northeast swell of 9 to 10 seconds across this area. With persistent fresh to strong northeast trade winds, the area of 12 ft or greater seas will expand westward to near 55W late tonight before they slowly subside from NE to SW going into Tue. For information east of 35W please read the latest High Seas Forecast issued by Meteo-France at website: https://wwmiws.wmo.int/index.php/metareas/affiche/2. For information west of 35W, please read the latest High Seas Forecast issued by the National Hurricane Center at website: https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml. ...MONSOON TROUGH/ITCZ... The monsoon trough axis enters the Atlantic near 07N12W and continues southwestward to 04N22W, where it transitions to the ITCZ to 03N32W to 02N48W. Numerous moderate to isolated strong convection is seen from the Equator to 06N east of 20W to inland over portions of western Africa. Scattered moderate convection is seen from S of 05.5N between 20W and 41W. ...GULF OF AMERICA... A stationary front extends southeastward across western Cuba, the Yucatan Channel and into the Yucatan Peninsula. A somewhat tight pressure gradient remains over the E and SE part of the basin where fresh to strong NE to E winds and moderate seas prevail. Near-gale NE winds are present over the Straits Florida according to the most recent ASCAT pass. Moderate to fresh NE to E winds are present over the eastern part of the basin along with moderate seas. Gentle to moderate NE to E winds and moderate seas prevail elsewhere across the basin. For the forecast, the aforementioned front will drift southward overnight. Strong northerly winds and rough seas following the front will gradually decrease by midweek. High pressure will dominate the Gulf region in the wake of the front Tue through Thu. The next cold front is expected to move into the NW Gulf Thu evening and reach from SW Florida to SE Texas Fri evening, then begin to lift northward and dissipate through Sat. ...CARIBBEAN SEA... A cold front is moving through the western Atlantic, with a large area of strong high pressure building in behind. The front is near the NW portion of the basin along NW Cuba and the Yucatan Channel to the northern Yucatan Peninsula. This front has weakened the pressure gradient slightly ahead of it with mainly moderate to locally fresh trades noted across most of the basin, highest in the S-central portion where the pressure gradient is the tightest due to low pressure near the northern coast of Colombia. Seas are 5-8 ft in the central Caribbean due to the persistent fetch of the trades, and 4-6 ft elsewhere except slightly lower between Cuba and Jamaica including the approach to the Windward Passage. Scattered moderate to isolated strong convection is confined to the far western section of the sea, due to the combination of low- level convergence of the trade winds along with instability provided by the close proximity of the eastern Pacific Ocean monsoon trough that extends eastward across southern Costa Rica and across Panama. Similar convection is also noted in the Gulf of Honduras due a surface trough. For the forecast, fresh trade winds and moderate seas will prevail over the south central Caribbean through Wed as Atlantic high pressure remains well NE of the region. Elsewhere, fresh to locally strong trade winds and rough seas in large E swell will persist over the tropical Atlantic waters, through the Atlantic passages and into the eastern part of the basin through Thu. An Atlantic cold front has moved across NW Cuba and the Yucatan Channel this evening and is accompanied by increasing winds and building seas. This front is expected to reach from central Cuba to near N Belize Tue morning, then will stall and gradually dissipate through Wed. High pressure will build into the W Atlantic Wed night through Thu to bring a return to fresh to strong trades across the central Caribbean into the weekend. ...ATLANTIC OCEAN... Please see the Special Features section for more information on two significant swell events, one for a portion of the northwest Atlantic waters, and the other in the eastern Atlantic. A cold front extends from near 31N56W to the SE Bahamas and across W central Cuba. In addition to the above mentioned swell behind the front, fresh to strong NE winds are also present. N of 29N and E of the front to 57W, fresh S-SW winds are present ahead of the front. Scattered moderate convection is noted along the front. High pressure of 1030 mb is N of the area near the Azores, with an associated ridge bridging across a dissipating front that extends from the Iberian Peninsula through 31N17W to 29N34W. This high combined with lower pressures to the S with the monsoon trough and ITCZ supports a large area of fresh to strong trades S of 26N and E of 55W where large swells are present as detailed above. Fresh to strong N-NE winds are also noted N of the front. Mainly moderate winds and 6-10 ft seas are present across the remainder of the open waters, except gentle winds and 5-8 ft seas S of 27N and W of 50W to the cold front. For the forecast W of 55W, a cold front extends from near 31N56W to the SE Bahamas and across W central Cuba. Strong northerly winds will gradually diminish tonight behind the front, except for a narrow band of strong NE winds along the front and W of 65W. The front will stall from 30N55W to the SE Bahamas and central Cuba by Tue morning, then slowly dissipate through Wed evening. Large N swell will continue to build across the regional waters behind the front through Tue night before subsiding. The Bermuda High will dominate the regional waters Thu through Fri. Low pressure is forecast to develop along the frontal remnants Thu, across the far NW offshore zones, and move northeastward and exit the area Thu night.