[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 121029
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1205 UTC Tue Jul 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 0600 UTC surface analysis and satellite imagery through
1015 UTC.

...TROPICAL WAVES...

An eastern Atlantic tropical wave has its axis along 25W from 04N
to 19N, moving westward at 10-15 kt. Clusters of scattered
moderate convection are noted within 240 nm E of the wave from
07N to 10N, and within 180 nm W of the wave from 06N to 10N.

A central Atlantic tropical wave has its axis along 47W/48W from
06N-20N. It is moving westward at 15-20 kt. Dry Saharan air is
preventing convection from developing north of 07N, but scattered
moderate convection is noted near the wave axis from 05N to 07N
between 45W-48W.

A central Caribbean tropical wave has its axis along 75W south
of 18N to inland central Colombia, moving westward at about 17 kt.
No significant convection is noted at this time with this wave.
Only isolated showers are possible along and near the wave axis
over Colombia.

The previous western Caribbean tropical wave has moved inland
over Central America. It is analyzed along 90W south of 19N
to the eastern Pacific Ocean, moving westward at 10-15 kt.
Increasing numerous moderate strong convection surging westward
is over the eastern Pacific waters southwest of Guatemala, El
Salvador and Honduras.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from the coast of Gambia near 13N17W
to 09N24W to 11N32W to 07N45W. The ITCZ extends from 07N49W to
the coast of Guyana near 08N59W. Aside from the convection
mentioned above, scattered moderate to isolated strong convection
is within 240 nm south of the trough between 28W-32W. Scattered
moderate convection that recently emerged off the coast of Africa
is seen from 05N to 11N between 13W-21W. Similar activity is
within 120 nm south of the trough between 40W-45W and within 60 nm
north of the trough between 35W-40W.

GULF OF MEXICO...

A weak surface trough near southeastern Louisiana in combination
with an upper-level trough is generating scattered showers and
isolated thunderstorms over the north-central Gulf. A weak ridge
oriented east-west roughly along 24/25N E of 90W continues to
dominate the remainder of the Gulf of Mexico, supporting gentle to
moderate south to southwest winds across the north-central and
northeast Gulf. An associated 1016 mb high center is analyzed near
24N84W. An overnight ASCAT satellite data pass showed gentle to
moderate east winds over the south-central Gulf. Gentle south to
southwest winds are over the far western Gulf. Seas are in the
range of 2-3 ft throughout the Gulf.

For the forecast, the weak ridge along 24N/25W E of 90W will
begin to shift northward on Wed. A weak surface trough that
extends from southeastern Louisiana to near 29N88W is expected to
linger in the vicinity of the north-central Gulf through Fri.
Instability created by this feature along with that of a nearby
upper-level trough should allow for very favorable conditions
leading to active weather impacting most of the central and NE
Gulf waters through the rest of the week. Low pressure may develop
from the surface trough later in the week. Light to gentle winds
are expected across the Gulf on Fri, except near the surface
trough and over the eastern Bay of Campeche where winds will be
enhanced by a thermal trough coming off the Yucatan peninsula at
night.

CARIBBEAN SEA...

A large upper-level low is centered near Puerto Rico and the
Virgin Islands. However, a large outbreak of dry Saharan air is
covering the eastern half of the Caribbean, limiting showers east
of 76W. The only area of showers east of 76W is present in the
southeastern Caribbean, south of 14N and east of 67W, where
broken clouds with isolated showers are present. Farther west,
isolated showers and thunderstorms are over the northwestern
Caribbean near the Cayman Islands and south of Cuba, enhanced by
a rather narrow upper-level trough that extends from Tampa Bay,
FL south-southwestward to Belize. In the southwestern Caribbean,
scattered moderate to isolated strong convection is noted in
association with the east segment of the eastern Pacific monsoon
trough south of 12N between 78W-81W. An overnight ASCAT satellite
data pass showed strong trade winds in the south-central Caribbean
Sea offshore northeast Colombia and in the Gulf of Venezuela.
Fresh trade winds are present elsewhere east of 80W from 10N-18N.
Mainly moderate trade winds continue elsewhere, except for fresh
in the Gulf of Honduras, and gentle south of Cuba. Seas are 6-8 ft
in the south-central Caribbean, 4-6 ft elsewhere over the eastern
and central Caribbean, and 2-4 ft in the NW Caribbean.

For the forecast, high pressure over the north-central Atlantic
will maintain moderate to fresh trade winds across the eastern
Caribbean, and fresh to strong trade winds in the central portion
of Caribbean through early Thu. The fresh to strong trade winds in
the central portion will diminish in coverage by Thu evening and
change little through Sat night. Gentle to moderate east to
southeast winds in the northwestern Caribbean will increase to
moderate to fresh on Tue, then diminish to gentle winds on Fri.
East winds in the Gulf of Honduras will increase to strong on Tue
night and continue to pulse at night through Thu.

ATLANTIC OCEAN...

An upper-level trough extending from Tampa Bay, Florida to Belize
is inducing isolated showers and thunderstorms over the NW
Bahamas and Straits of Florida. Another upper-level low is located
near Puerto Rico and the Virgin Islands, but dry Saharan air as
observed in the GOES-E RGB dust imagery is preventing any showers
from developing in the area. Elsewhere, the subtropical Bermuda-
Azores High continues to dominate the Atlantic. The subtropical
ridge axis stretches west-southwestward from a 1028 mb high
pressure center located well north of the area at 37N32W to
31N50W to 27N65W and to the Florida Keys. Gentle to moderate winds
are present across the entire area north of 20N and west of about
47W along with seas of 4-6 ft as noted in a couple of overnight
altimeter data passes. Latest ASCAT data passes depict fresh to
strong northeast winds east of 35W and north of 20N, where seas
are likely 7-10 ft. In the tropical Atlantic, fresh northeast to
east trade winds and seas of 6-8 ft are present from 10N-20N
between 35W-60W as were detected by the overnight altimeter data
passes.

For the forecast west of 55W, the aforementioned high
pressure ridge will build westward on Tue, then begin to lift
northward on Wed, reaching near 30N on Thu and to N of 31N Fri
allowing for moderate to fresh south to southwest winds over the
waters east of NE Florida to become light to gentle southeast to
south winds Fri through Sat night. Moderate to fresh east winds
will continue south of 25N through the next few days, except
between the southeastern Bahamas and Hispaniola, where winds will
be fresh to strong at night.

$$
Aguirre
This weather bulletin was brought to you by:
www.nashvilleweather.net