AXNT20 KNHC 120530
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0605 UTC Fri Aug 12 2022
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 0000 UTC surface analysis and satellite imagery through
The axis of a tropical wave is along 44/45W from 03N-23N, moving
westward at 20 kt. A large envelope of moist air is seen in Total
Precipitable Water imagery, in association with the tropical
wave. Scattered moderate convection is noted within 270 nm either
side of the wave axis from 08N to 14N.
The axis of a tropical wave is along 57W from 20N southward to the
Suriname/Guyana border, moving westward at 15 kt. The portion of
the wave north of 12N is currently enveloped in an area of
westward moving Saharan dust. No significant convection is noted
with the wave at this time.
The axis of a central Caribbean tropical wave is along 70W from
the Dominican Republic southward to western Venezuela, moving
westward at 15 kt. No convection is noted with the wave at this
time over water, but scattered showers and isolated thunderstorms
are noted over Hispaniola.
The axis of a tropical wave is along 95W, extending from the Bay
of Campeche near 20N southward through Oaxaca, Mexico and into the
east Pacific. The tropical wave is moving W at 10 kt. Isolated
moderate to strong convection is noted over the eastern Bay of
Campeche as well as over portions of the Mexican states of Oaxaca,
NW Chiapas, SW Tabasco, and SE Veracruz.
The monsoon trough extends from the coast of Senegal near 14N17W
to 12N24W to 13N38W to 11N53W. Aside from the convection
mentioned in the tropical waves section above, scattered moderate
isolated strong convection is noted from 07N to 12N east of 23W,
and from 08N to 11N between 33W and 36W.
GULF OF MEXICO...
A trough over the NW to west-central Gulf of Mexico extends from
the surface up to the mid-troposphere near 500 mb. Abundant
moisture is seen over the NW Gulf in Total Precipitable Water
imagery. Although the coverage and intensity of thunderstorms in
the Gulf has diminished significantly overnight compared to during
the daytime on Thursday, expect thunderstorms to return to the
northwest Gulf during the daytime today as the trough and moisture
sticks around. This activity will then continue over the northern
Gulf waters through Sat before shifting across the NW Gulf Sun as
a frontal boundary stalls near the northern Gulf coast. Locally
gusty winds and rough seas are possible within the stronger
Weak high pressure ridging extends from the western Atlantic
westward along 29N to 1018 mb high pressure just offshore the
Florida Big Bend near 29N83.5W to the N central Gulf. Buoys are
currently reporting gentle to moderate wind speeds and 2 to 4 ft
seas across the basin. A recent ASCAT satellite wind data pass
also shows gentle to moderate wind speeds across most of the
basin. The high pressure ridge will shift east-southeast late
today through Sun. This will allow for gentle to moderate winds
over the basin to weaken to light to gentle into next week.
Moderate NE to E winds will pulse to fresh during the late
afternoon and evenings off the NW Yucatan peninsula through early
A broad upper-level low is centered just east of the Bahamas near
25N74W. An upper-level trough axis extends southwestward from
there to eastern Cuba and westward to the Yucatan Peninsula.
Upper-level diffluence is enhancing scattered showers and
thunderstorms just south of Cuba and over the waters near the
Tiburon Peninsula of Haiti. Isolated showers and thunderstorms are
occurring over the SW Caribbean in association with the east
Pacific monsoon trough. The remainder of the basin is not
currently experiencing any significant precipitation.
A recent ASCAT satellite wind data pass shows mainly moderate
trade winds over the basin. Gentle E winds are likely occurring
over the NW Caribbean. A 11/2300 UTC altimeter pass shows seas of
5 to 6 ft in between Jamaica and Panama. NOAA buoy 42059 near
15.3N 67.5W is reporting a significant wave height of 5 ft. Seas
across the basin are averaging 4 to 6 ft.
The Atlantic ridge extends from the central Atlantic W-SW to
northern Florida along 29N, and will weaken through early next
week. Fresh trade winds over the central Caribbean will weaken to
moderate Sat through Mon, then increase back to fresh late Mon
through Tue night. Active weather is possible in the central
Caribbean through the upcoming weekend as an upper-level trough
parks itself over the Bahamas and Cuba. A broad tropical wave,
currently along 45W, is expected to reach the Lesser Antilles Sat
night into Sun, move across the eastern Caribbean Sun through
early Mon, and across the central Caribbean Mon through Tue night.
A broad upper-level low is centered just east of the Bahamas near
25N74W. Ridging in the low and mid levels to the north of 27N is
allowing for only scattered weak showers over the area from 27N-
31N between 69W-75W. A 1019 mb high is centered near 30N76W. This
high is along a surface ridge axis that extends from 32N60W to
30N76W to 29N83W. A recent ASCAT pass shows gentle or weaker winds
from 26N-31N between 55W-82W. Seas are near 3 ft across that
entire area. Moderate trades prevail through the Bahamas and north
of the Greater Antilles, except for fresh north of Hispaniola and
in the Windward Passage. Seas are likely near 5 ft in this area.
Another upper-level low centered near 29N57W is enhancing
scattered showers and isolated thunderstorms from 28N-31N between
47W-61W. A surface trough extending from 31N59N to 29N61W is
contributing to that activity. A 1025 mb surface high pressure is
centered near 31N36W. Moderate to fresh trades and 5-7 ft seas
prevail from the monsoon trough to 27N between 30W-55W. Strong NE
winds and 7-10 ft seas are likely occurring from 17N-24N between
the coasts of Mauritania/Western Sahara and 27W. Gentle winds
prevail from 27N-31N between 25W-55W with 3-5 ft seas.
The ridge extending from the central Atlantic W-SW to northern
Florida along 29N will weaken through early next week as a frontal
boundary moves off the eastern seaboard and stalls over the waters
east of NE Florida. Moderate to fresh E winds S of 25N will veer
to the SE and weaken to gentle early Sat and change little into
next week. Light to gentle variable winds are expected elsewhere
through the period. A tropical wave will reach the southeast
forecast waters between 55W-65W by Sat, bringing a slight increase
in winds and seas over those waters through early on Mon.