AXNT20 KNHC 251805

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
105 PM EST Sun Feb 25 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 1200 UTC surface analysis and satellite imagery through 1745 UTC.


A rapidly intensifying low pressure system over the north-central Atlantic supports a cold front N of the area that will enter forecast waters along 31N35W to 28N43W to 31N57W early Monday morning. A strong pressure gradient between this broad low and surface ridging to the west-southwest will lead to the development of gale-force winds north of 30N east of 40W. Gale conditions are forecast to prevail through early Tuesday morning. For more details, refer to the NHC High Seas Forecast under AWIPS/WMO Headers MIAHSFAT2/FZNT02 KNHC.


The monsoon trough enters the eastern Atlantic near 04N08W and continues to 02N16W. The ITCZ extends from that point to the coast of Brazil near 02S43W. Scattered moderate convection is from 01S-05N between 15W-25W and from 03S-04N W of 39W. Numerous strong convection is N of 3S E of 01W.



Deep layer dry air prevails across much of the basin, except for the far western Gulf where middle to upper level moisture is being advected from the EPAC by southwesterly flow. CIRA microwave imagery at the lower level show shallow moisture in the same region of the Gulf, which is being advected from the Caribbean by southeasterly wind. This moderate low level moisture is allowing for the continuation of dense fog and haze N of 27N W of 90W. With ridging anchored in the SW N Atlc, moderate return flow dominates across the basin, except in the Bay of Campeche where latest scatterometer data show fresh SE winds. By early Monday, a low pressure center will develp over eastern Texas, thus transitioning a stationary front into a cold front forecast to extend from the Florida Panhandle SW to Brownsville, Texas by Monday night. The front will stall again shortly thereafter and then lift northward along the Gulf coast through Tuesday morning. Scattered showers and and tstms will accompany this boundary.


Stable and fair weather conditions reign in the western half of the Caribbean as deep layer dry air prevails. However, the eastern half of the basin is under the influence of a middle to upper level low that along with shallow moisture moving across the region support scattered to isolated showers across Hispaniola, Puerto Rico and southern adjacent waters. With broad surface high pressure N of the area, trades are mainly moderate, except in the central portion of the basin where fresh winds are the norm. Along the coast of Colombia, winds increase to strong. No major changes expected through Tuesday.


Gale-force winds are forecast to develop over northeast Atlantic waters by early Monday morning. See the Special Features section above for further details. A broad surface ridge prevails across the west and central Atlantic anchored by a 1026 mb high near 30N68W. Moderate to fresh winds are noted in the approaches of the Windward Passage forecast to increase to fresh to strong at night the next two days. To the east, a low pressure system over the northeast Atlantic continues to support a cold front that enters the area of discussion near 30N17W to 20N23W to 16N36W. The high pressure system will remain nearly-stationary while weakening through Tuesday morning.

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

$$ Ramos