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AXNT20 KNHC 211754

TWDAT 



Tropical Weather Discussion

NWS National Hurricane Center Miami FL

1805 UTC Sun Apr 21 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 1200 UTC surface analysis and satellite imagery through 

1700 UTC.



...SPECIAL FEATURE...



Developing western Atlantic gale...

1011 mb low pressure is along the Atlantic coast near the border

of North and South Carolina, along a cold front that extends from

the northern Gulf of Mexico across the SE U.S. and into the

western Atlantic. The cold front is expected to sink slowly SE

today through Mon night, moving into the waters offshore of NE

Florida this evening and across the NW forecast waters Mon and Mon

night. The current low pressure along the Atlantic coast will move

eastward, and remain just N of 31N, and gradually strengthen through

Mon, then begin to lift off to the NE Mon evening and night.

Strong northerly winds will fill in behind the front and across

the western semicircle of the low Mon, and increase to gale-force

Mon afternoon through early Tue morning, before diminishing

quickly Tue morning, as the low move well N of the local Atlantic

waters. Seas will build to 8-15 ft in N to NE swell during the

period of gales. 



...MONSOON TROUGH/ITCZ...



The monsoon trough passes through the coastal plains of Guinea-

Bissau near 11N16W and extends to 04.5N25W. The ITCZ extends from

02N28W to coastal Brazil near 00N49W. Scattered to locally 

numerous moderate to strong convection is noted from 03.5N to 

08.5N between 04W and 18W, and extends well inland across Africa. 

Scattered moderate isolated strong convection is S of 05N between

18W and 48W, and S of 07N between 48W and 53W. 



...GULF OF MEXICO...



A cold front has moved into the northern Gulf this morning, and 

at 1200 UTC extended from the western Florida Panhandle to across

the Brownsville, Texas area. A trough resides just ahead of the 

front and extends from central portions near 25N90W to the Mexican

coast near Veracruz. Western Atlantic high pressure extends a 

ridge westward along 27N, across Florida, and into the eastern 

Gulf ahead of the front. A short wave upper trough sweeping across

the western Gulf is supporting scattered showers and 

thunderstorms on both sides of the front, from 21N to 28N to the

west of 93.5W, and north of 26.5N between 83W and 88W. Recent

midday satellite scatterometer winds depicted strong northerly

winds to 30 kt behind the front and west of 92W, where seas have

built to 7-9 ft. Fresh NW to N winds are elsewhere behind the

front E of 92W, with seas 3 to 6 ft. Moderate to fresh northerly

winds across SW portions of the basin, to the west of the surface

trough, where seas remain 5-6 ft from an overnight pulse of winds.

Moderate or less winds prevail elsewhere across the basin, with

seas 3 to 5 ft, except 2 ft or less NE portions. 



For the forecast, the front will reach from N-central Florida to 

the W-central Gulf to Veracruz, Mexico this evening, then will 

weaken and eventually wash out as it pushes through the southern 

Gulf by Mon evening. Fresh to strong winds and building seas will 

follow the front through early Mon, lingering offshore of Veracruz

through Mon evening. High pressure will rebuild in the wake of 

the front, with gentle to moderate winds across the NE half of the

basin, and moderate to fresh across the SW half, pulsing to fresh

to strong NW of the Yucatan Peninsula at night. 



...CARIBBEAN SEA...



A broad and weak Atlantic high pressure ridge is along 27N and N 

of the basin, producing a modest pressure gradient across the

Caribbean. Fresh winds are S of Hispaniola, just offshore of Colombia,

and downstream of the Windward Passage between Jamaica and Cuba. 

Gentle to moderate trades prevail elsewhere, and become SE across

the Yucatan Channel. Seas are 5 to 6 ft in the areas of fresh winds,

and 3 to 4 ft elsewhere. Scattered moderate thunderstorms persist

across the coastal waters south of 10N from NW Colombia to eastern

Panama. The lingering remnants of an old frontal trough extend

from the NE Caribbean along 18N westward to south of Puerto Rico.

A cluster of scattered moderate convection continues across the

waters surrounding St Croix, while other light convection dots the

waters between Haiti, Jamaica, and eastern Cuba.



For the forecast, the broad subtropical ridge north of the 

Greater Antilles will support pulsing fresh to strong winds just 

offshore N Colombia tonight and again Wed night. Otherwise 

moderate to locally fresh trades will prevail across the central 

and eastern Caribbean. Mainly gentle to moderate trades will 

prevail elsewhere, pulsing to moderate to fresh from the Lee of 

Cuba to the Windward Passage, and offshore central Honduras at 

times. A decaying cold front may reach into the Caribbean N of 20N

Mon night, possibly bringing a brief period of active weather. 

Slight to moderate seas will prevail across the basin. 



...ATLANTIC OCEAN...



West Atlantic ridging extends from 1022 mb high pressure near

31N54W through 28N58W and across south Florida along 27N and into

the eastern Gulf of Mexico. Another ridge extends from 31N27W 

through 22N42W. Light to gentle winds are right under the ridges,

with gentle to moderate along the peripheries. Seas are 3 to 6 ft

across most of the basin. Separating the ridges, a 1012 mb surface 

low is near 27.5N40W with a cold front extending southwestward to

22N46W then transitions to a trough extending to the Leeward

Islands near 17N62W. Scattered moderate convection is noted N of 

27N between 38W and 30W. Fresh to strong winds surround the low

center and extend NE to beyond 31N. Seas are 5 to 8 ft across

these NE forecast waters. Moderate to fresh winds are from the 

Cabo Verde Islands to the Canary Islands offshore western Africa 

to 23W, with 5 to 7 ft seas there.



See the Special features section for information on gale

conditions expected across the NW waters. 



For the forecast, high pressure over the basin will continue to 

prevail ahead of a cold front which will move offshore NE Florida 

this evening, reaching from 31N73W to near Stuart, Florida Mon 

evening, from just E of Bermuda to the SE Bahamas Tue evening, 

then stalling and dissipating to a trough from near 31N59W to the 

Turks and Caicos Islands by Wed evening. Fresh to strong winds and

building seas will follow the front, mainly N of 27N, increasing 

to gale speeds Monday afternoon. Seas will build to 14 ft with the

strongest winds. The trough is forecast to linger through the 

remainder of the week with mainly tranquil conditions for the end 

of the week.



$$

Stripling