AXNT20 KNHC 081655
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Mon Aug 8 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 1200 UTC surface analysis and satellite imagery through
An eastern Atlantic tropical wave has its axis along 21W, south of
20N, moving W at 10-15 kt. Scattered moderate to isolated strong
convection is observed from 08N to 15N and between 18W and 30W.
Environmental conditions appear generally favorable for gradual
development and a tropical depression may form around the middle
to latter part of the week as the wave moves into the central
tropical Atlantic. The current outlook states that the disturbance
has a medium chance of development during the next 5 days.
Another eastern Atlantic tropical wave has its axis along 37W,
south of 20N, moving W at 15-20 kt. Scattered moderate convection
is noted from 10N to 15N and between 34W and 39W. Dusty Saharan
air encompasses the wave axis N of 15N, maintaining dry
A central Atlantic tropical wave has its axis along 50W, south of
19N, moving W at 15-20 kt. No deep convection is present near the
A central Caribbean tropical wave has its axis along 73W, south of
21N, moving W at 10-15 kt. This wave is underneath an upper-
level trough. This feature is supporting an area of scattered
moderate convection that trails the wave from 14N to 21N and
between 69W and 72W.
The monsoon trough enters the Atlantic through the coast of
Mauritania near 21N16W to 12N21W to 15N28W to 12N36W to 11N52W.
The ITCZ extends from 11N52W to 09N61W. Aside from convection
associated to tropical waves, scattered moderate convection is
evident within 90 nm on both sides of the monsoon trough between
40W and 49W.
GULF OF MEXICO...
An upper level low in the western Gulf of Mexico and a weak
surface trough in the central Bay of Campeche are interacting with
plenty of moisture to produce scattered showers and isolated
thunderstorms in the SW and western Gulf. Another upper level
disturbance off the SE US coast is also inducing divergence over
the NE Gulf, resulting in scattered showers over the eastern
portion of the basin. The Gulf remains under the influence of a
weak high pressure regime, sustaining light to locally moderate
easterly winds E of 90W and light to gentle winds elsewhere. Seas
are 2-4 ft across the Gulf.
Expect locally stronger winds and rough seas in and near
scattered showers and thunderstorms.
For the forecast, a nearly stationary upper-level low is over the SW
Gulf and will maintain active weather across the W Gulf through this
evening. Fresh NE to E winds will briefly pulse to strong in the
eastern Bay of Campeche Tue night. A mid to upper-level trough
just east of NE Florida will shift to the NE Gulf today through
Tue night and to the north-central and NW Gulf Wed through Fri
enhancing shower and thunderstorm activity across those sections
of the Gulf. Otherwise the Atlantic surface ridge will extend W
along about 31N through late Wed before weakening W of 90W.
Aside from the convection associated with the tropical wave in the
central Caribbean, low level convergence is supporting a line of
showers and isolated thunderstorms in the SW Caribbean, mainly S
of 17N and W of 78W, also impacting eastern Nicaragua and NE Costa
Rica. Elsewhere, fairly tranquil weather conditions prevail. A
recent scatterometer satellite pass show fresh to strong easterly
trade winds in the central Caribbean, with the strongest winds
found south of Hispaniola, off NW Colombia and in the Windward
Passage. Seas are 6-8 ft in the central Caribbean. Moderate to
fresh easterly winds are noted in the eastern Caribbean and in the
lee of Cuba, along with seas of 4-6 ft. In the rest of the basin,
gentle to moderate winds and seas of 2-4 ft are prevalent.
For the forecast, fresh to strong trade winds over the south-central
Caribbean will continue pulsing through the forecast period. A
tropical wave across the central Caribbean will be accompanied by
scattered showers and thunderstorms, gusty winds and rough seas
as it continues westward across the remainder of the basin
through early Wed. Fresh winds will pulse in the Gulf of Honduras
at night through the week. The next tropical wave will move
across the Tropical N Atlantic waters early Tue through Wed night
and across the eastern Caribbean Thu through Fri night enhancing
shower and thunderstorm activity over those waters.
An upper level trough near the Bahamas is supporting scattered
showers S of 24N and between 70W and 77W. Another area of showers
is noted off NE Florida in association with a weak surface trough.
The remainder of the western Atlantic remains under the dominion
of a 1025 mb high pressure system near Bermuda. The pressure
gradient between the aforementioned subtropical ridge and lower
pressures in the Caribbean results in fresh to locally strong
easterly winds S of 25N and between 60W and 77W. Recent
satellite-derived wind data indicate that the strongest winds are
occurring off northern Hispaniola, NE Cuba and the entrance of the
Windward Passage. Seas are 5-8 ft in these waters. Light to
moderate anticyclonic winds are present in the rest of the western
Atlantic, especially W of 55W. Seas are 3-6 ft in the described
The central and eastern tropical Atlantic are under the influence
of a broad subtropical ridge positioned in the NE Atlantic and
together with a dry and dusty Saharan airmass, maintain fairly
tranquil weather conditions. Fresh to locally strong NE winds are
noted N of 21N and E of 27W, along with seas of 5-8 ft. Elsewhere
in the basin, moderate or weaker winds and seas of 4-7 ft prevail.
For the forecast west of 55W, the Atlantic ridge will remain
centered just W of Bermuda and dominate the forecast region
during the next several days. Moderate to fresh winds will prevail
S of 25N through the forecast period. Fresh to strong winds will
pulse north of Hispaniola and in the approaches to the Windward
Passage during the late afternoons and overnight hours through Wed
night. A surface trough extends from 31N76W to 27N78W and will
shift W and inland through this evening accompanied by scattered
showers and thunderstorms.