000
AXNT20 KNHC 251040
TWDAT
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1205 UTC Thu Apr 25 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 0600 UTC surface analysis and satellite imagery through
1030 UTC.
...SPECIAL FEATURES...
East Atlantic Gale Warning: Low pressure of 1008 mb is centered
near 22N37W moving south-southwest. A tight pressure gradient
between the low and strong high pressure to the north has induced
near gale to gale-force winds of 30-35 kt within about 90 nm of
the low in the NW and N quadrants. An ASCAT pass from Wed evening
revealed these winds. Seas with these winds are 10 to 13 ft. As
the low pressure continues to move south-southwestward early this
morning, it will undergo weakening and the culprit tight pressure
gradient will relax enough to allow for the gale-force winds to
diminish to just below gale force. Seas will remain at 10-13 ft in
the NW and N quadrants of the low. The seas will begin to slowly
subside later in the morning and into the afternoon. Please read
the latest High Seas Forecast issued by the National Hurricane
Center at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more
details.
Heavy Rainfall In Hispaniola: A persistent surface trough extends
from near 31N51W southwestward to 25N56W and to 19N64W. To its
west, a stationary front extends from 31N60W to 24N66W and to
20N74W. The combination of a moist and unstable environment
between these two features and the additional ingredient of
a very moist southwest to west flow aloft is favorable for the
development of numerous showers and strong thunderstorms over and
near Hispaniola this afternoon and early evening. This activity is
capable of producing heavy downpours, increasing the chance for
flash flooding, especially in hilly terrains and low-lying areas.
Please refer to local weather service offices for more details on
this event.
...MONSOON TROUGH/ITCZ...
The monsoon trough axis passes through the coastal border of
Sierra Leone and Liberia southwestward to 02N16W and to the
Equator at 20W, where latest scatterometer data indicates the ITCZ
begins and continues along the Equator to 30W and to 38W.
Scattered moderate to isolated strong convection is seen from 01N
to 06N between 20W-25W, and within 60 nm west-southwest of the
ITCZ between 37W-39W. Scattered moderate convection is within 60
nm south of the ITCZ between 30W-34W, and within 60 nm of 02N46W.
...GULF OF MEXICO...
A 1021 mb high pressure center is analyzed over the NE Gulf near
29N87W. A ridge extends from the high westward to central Texas
coast, with associated anticyclonic flow covering the entire
basin. An inland Mexico surface trough curves through the Yucatan
Peninsula, to the Isthmus of Tehuantepec of southern Mexico,
northwestward. Both partial ASCAT data and buoy observations
indicate light to gentle winds over the NE Gulf and gentle to
moderate winds elsewhere, except for slightly higher winds of
fresh speeds over the western Gulf and central Bay of Campeche.
Seas are in the 3 to 5 ft range, except for slighter higher seas
of 4 to 6 ft over the NW Gulf and west-central Gulf sections.
For the forecast, the high pressure of 1021 mb centered over the
NE Gulf near 29N87W will maintain light to gentle winds over that
part of the Gulf today, and for moderate to fresh southeast winds
over most of the western part of the Gulf. The pressure gradient
will tighten over the Gulf beginning tonight resulting in
increasing east to southeast fresh to strong winds over just about
the entire basin through Sun night. Seas will build to 10 ft in
the NW Gulf on Sun. Meanwhile, winds will pulse to fresh to strong
speeds near the Yucatan Peninsula each evening through the
period.
...CARIBBEAN SEA...
Please read the Special Features section for details about the
potential for heavy rainfall in Hispaniola.
Western Atlantic high pressure extends south over the northwestern
part of the Caribbean. The pressure gradient between the high
pressure and relatively lower pressure in the southern section of
the basin is allowing for fresh to strong winds to exist in the
south-central Caribbean to along the coast of Colombia and in the
Gulf of Venezuela. Fresh northeast winds are in the lee of Cuba,
in the Windward Passage and just south of the Dominican Republic.
A surface trough extends from the central Atlantic southward to
Puerto Rico and to near 16N67W. Isolated showers are possible near
the trough.
Moderate to fresh trade winds are elsewhere over the basin,
except for fresh winds from 11N to 15N between 76W and 80W,
south of 15N east of 72W and in the Windward Passage. Seas are in
the 4 to 6 ft range, except for slightly lower seas of 3 to 5 ft
north of 15N west of 64W and in the Gulf of Honduras.
Isolated showers are possible over the central Caribbean.
For the forecast, high pressure north of the Greater Antilles is
sustaining moderate to fresh trade winds, except for fresh to
strong winds in the Windward Passage and in the south-central
Caribbean. The gradient associated to the high pressure will
maintain fresh to strong winds just north of Colombia, through the
Windward Passage, and in the lee of Cuba through this morning.
Looking ahead, strengthening of the high pressure beginning late
Fri will also force fresh to strong trade winds in the Gulf of
Honduras, lee of Cuba, Windward Passage and just south of
Hispaniola through early next week.
...ATLANTIC OCEAN...
Please read the Special Features section for details about the
potential for heavy rainfall in Hispaniola, and for details on
soon to end gale-force winds related to low pressure in the
eastern Atlantic.
A stationary front is analyzed from 31N60W to 24N66W and to near
eastern Cuba. A trough extends from just south of the front at
26N63W south to across Puerto Rico. A 1022 mb high center is just
southwest of Bermuda near 32N66W. Latest ASCAT data shows
moderate to fresh northeast winds south of 24N between 70W and
77W. Fresh northeast winds are in the Windward Passage. The ASCAT
data also reveals mainly gentle to moderate winds elsewhere west
of 55W, except for light to gentle winds north of 27N and west of
the frontal boundary. Satellite imagery shows an area of scattered
showers and isolated thunderstorms near the stationary front and
northern part of the trough from 25N to 28N between 60W and the
front. Small isolated showers and thunderstorms are seen south of
about 24N between the trough and 70W.
In the eastern Atlantic, a rather large surface trough is east
of the Special Features low along a position from near 25N26W
southwestward to 17N33W, to 13N38W and to near 10N47W. No
significant convection is occurring with this trough, however,
an area of increasing numerous showers and thunderstorms is to
its northwest from 25N to 31N between 27W and 33W. This activity
is due to a rather robust upper trough that extends from an
upper- level cyclonic circulation near 30N31W southeastward to
27N30W and southwestward to near 21N34W. Aside from conditions
associated directly with the Special Features low, relatively
weak high pressure is present over the eastern and central
Atlantic. Stronger high pressure ridging is just north of the
area. A broad area of fresh to strong northeast to east winds is
noted north of 22N and east of 50W. Strong to near gale force
northeast winds are closer to the low. An overnight ASCAT pass
captured some of these winds. Seas with these winds are in the 9
to 13 ft range. Moderate or weaker winds easterly winds are over
the remainder of the basin along with generally moderate seas.
For the forecast W of 55W, the aforementioned stationary front is
forecast to weaken to a trough by this evening. A cold front is
forecast to merge with the trough and progress eastward, reaching
from near 31N57W to eastern Cuba early Sat morning, from near
25N55W to Hispaniola early Sun, then stall and weaken into a
trough over the far southeastern part late Sun through Mon night.
North swell behind the front will build seas over most of the area
northeast of the Bahamas by Sun. Strengthening high pressure in
the wake of the front will result in fresh to strong north to
northeast winds behind the front from late Fri through Sun. By
late Sun, these winds are expected to be at mainly fresh speeds
south of 29N and west of 60W. At that time, fresh to strong west
to northwest winds are expected over the far northeast forecast
waters along with building seas.
$$
Aguirre
