Atlantic Tropical Weather Discussion


  275  AXNT20 KNHC 110006 TWDAT   Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Mon Mar 11 2024  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 31N. 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.  ...SPECIAL FEATURES...  Western and Central Atlantic Significant Swell: Large, long-period N swell produced by earlier storm-force winds associated with a low at the north-central Atlantic continue to propagate south of 31N. Seas are 12 to 14 ft north of 29N between 46W and 59W, but are expected to build to 16 ft and spread SE to near 27N between 39W and 55W by early Mon morning before subsiding below 12 ft Monday evening.  A deepening frontal low is exiting into the NW Atlantic from the  NE United States. Expected storm-force winds related to this low  will generate even larger NW swell southward across the western  Atlantic, passing 31N by mid Monday morning. Seas north of 27N  between 57W and 74W are going to rise steadily and reach 12 to 20  ft by Monday evening. These high to very high seas will then shift southeastward to near 25N between 47W and 70W by noon Tuesday,  and to near 23N between 40W and 62W by noon Wednesday. After  midweek, these seas should gradually subside while continue  shifting eastward.  Caribbean Gale Warning: A strong high pressure is forecast to exit the Georgia and NE Florida coast on Monday. Tight gradient between this high and the Colombia Low is anticipated to produce strong to near-gale NE  winds off the northwestern Colombia coast most of this week. These winds will pulse to gale-force during the nighttime and early  morning hours through Wednesday morning. Seas under the strongest  winds will peak between 10 and 12 ft.  Mariners need to monitor these hazardous marine conditions and  plan their route accordingly. Please read the latest High Seas and Offshore Waters Forecasts issued by the National Hurricane Center at websites: https//www.nhc.noaa.gov/text/MIAHSFAT2.shtml and www.nhc.noaa.gov/marine/offshores.php for more details.  ...MONSOON TROUGH/ITCZ...  The monsoon trough enters the Atlantic through the coast of  Guinea near 09N13W, then runs southwestward to 01N20W where it transitions to the ITCZ that continues to 01S30W to 00N43W.  Widely scattered moderate convection is from 09S to 07N W of 23W.  ...GULF OF MEXICO...  A cold front extends from southern Florida to the Yucatan Peninsula followed by moderate NE winds, except for fresh to strong winds over the SE basin and the Yucatan Peninsula adjacent waters. Seas are moderate basin-wide, except for the aforementioned region where the strongest winds lie.   For the forecast, the cold front will stall and weaken tonight  across the western Caribbean Mon. Fresh to strong northerly winds  and moderate to rough seas are expected in the wake of the front.  Conditions will improve early this week as high pressure builds in the wake of the front.   ...CARIBBEAN SEA...  Please see SPECIAL FEATURES section about an upcoming gale  warning.  Moderate to fresh trade winds are across the southern Caribbean, except for fresh to strong winds in the Gulf of Venezuela and off the coast of Colombia where seas are moderate. Outside of the southern basin, seas are slight.    For the forecast, high pressure NE of the area combined with low  pressure over Colombia will support a small area of fresh to  strong over the south-central Caribbean through early Mon. High  pressure will start to build N of the area Mon, bringing a slight  increase in coverage of the fresh to strong winds, and a pulsing  of gale-force winds Mon night and Tue night. Gentle to moderate  winds will prevail elsewhere. A weakening cold front will approach the Yucatan Channel and western Cuba tonight.  ...ATLANTIC OCEAN...  Please see SPECIAL FEATURES section for details on a significant  northerly swell event.   A cold front extending from 33N71W to southern Florida is providing fresh to strong NW winds and rough seas to 9 ft to the offshore waters N of 26N and W of 70W. Ahead of the front, fresh to strong SW winds are ongoing reaching as far as 62W. South of 27N and in the SW N Atlantic waters, winds are gentle to moderate and seas in the 4-7 ft range. In the central subtropical Atlantic, a cold front extends from 31N42W to 26N53W where it transitions to a stationary front to 27N59W, then to a warm front to 31N62W. Over this central subtropical region winds are light to gentle, but the main concern is the large swell generating waves heights to 15 ft. However, ahead of this front, fresh to strong SW winds are ongoing N of 26N to 31W and seas are 7-9 ft. Surface ridging dominates the eastern Atlantic subtropical waters where recent scatterometer data show gentle to moderate NE to E winds. Although winds are not significant, large long-period NW swell is affecting that region with rough seas to 12 ft.   For the forecast W of 55W, the cold front will reach from Bermuda to western Cuba tonight. The northern portion of the front will  continue moving to the east of the region Tue, leaving a weakening front extending to the Windward Passage by early Tue. Strong to  near-gale force winds and rough to very rough seas will accompany the front mainly north of 24N, through the early part of the  week. Winds will diminish from west to east into mid week as high  pressure builds in the wake of the front. Combined seas in excess  of 8 ft may linger east of 70W through mid week due to associated  northerly swell.   $$ Ramos