AXNT20 KNHC 121732
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 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 1200 UTC surface analysis and satellite imagery through
The next tropical wave has entered the Atlantic Ocean. The
tropical wave is along 18W, from 20N southward, with an estimated
westward motion of 10-15 kt based on 700 mb wind speeds. 1010 mb
low pressure is along the wave axis near 13N18W. Scatterometer
data from this morning depicts moderate to fresh winds in the
vicinity of the wave axis. Scattered moderate convection, enhanced
by the Monsoon Trough, is west of the wave axis from 08N to 11N
between 18W and 25W.
A tropical wave is along 49.5W, from 23N southward, moving
westward at 15-20 kt. Scattered moderate convection is from 09N to
13N between 46W and 48W and from 09N to 11N between 48W and 52W.
A tropical wave approaching Barbados is along 59W, from 21N
southward, moving westward at 10-15 kt. No convection is noted
with the wave at this time.
A tropical wave located in the central Caribbean is along 73W,
from 20N southward, moving westward at 10-15 kt. Scattered
moderate convection is east of the wave axis, from 16N to 19N
between 68W and 70W, including coastal sections of Hispaniola.
The monsoon trough extends from the coast of Senegal near 15N17W
to 1010 mb low pressure near 13N18W to 14N46W to 09N59W. Scattered
showers are along the boundary.
GULF OF MEXICO...
1014 mb low pressure is centered in the NW Gulf near 29N92W, with
a trough extending from the low southwest to 25N97W. These
features, combined with broad surface convergence across the
north-central and northeast Gulf, is producing scattered moderate
convection north of 24N between 85W and 96W. Winds and seas may be
locally higher in the convection. Elsewhere in the Gulf of Mexico,
gentle to moderate SE to S winds prevail along the periphery of
the subtropical Atlantic ridge, with seas of 2-4 ft.
For the forecast, weak high pressure extending from the western
Atlantic westward along 29N to the N central Gulf will sink
southeast from late this afternoon through Tue. 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 next week. Scattered showers and
thunderstorms will continue over the northern Gulf waters through
early Sat, then shift across the NW Gulf Sat through Sun as a
surface trough lingers over the north-central Gulf with low
pressure along it. At the same time, a weak frontal boundary is
expected to stall just north of the central and NE Gulf.
The latest scatterometer data depicts gentle to moderate trades in
the eastern and central Caribbean, with light to gentle trades in
the western Caribbean. The trades have slowed in recent days as
the Bermuda-Azores high retreats further north and the pressure
gradient over the Caribbean relaxes. 1010 mb Colombian/Panamanian
low is in the SW Caribbean near 11N81W, along the extension of the
East Pacific Monsoon Trough. Scattered moderate convection is to
the northwest of the low, from 11N to 14N west of 81W including
coastal regions of Nicaragua.
For the forecast, The Atlantic ridge will weaken through early
next week. Moderate to fresh trade winds over the central
Caribbean will weaken to moderate Sat through Mon, then increase
to fresh late Mon through Tue night. A broad surface trough
accompanies a tropical wave across the central Atlantic, and is
expected to move across the Tropical N Atlantic Fri night through
Sat night, across the eastern Caribbean early Sun through early
Mon, and across the central Caribbean Mon through Tue night.
An outflow boundary is analyzed in the deep tropics, from 12N39W
to 11N41W to 09N40W, moving quickly west at 25-30 kt. E winds to
30 kt were captured well in scatterometer data this morning behind
the boundary. The remainder of the tropical Atlantic continues to
be dominated by the subtropical ridge located north of the area.
NE to E winds are gentle to moderate across the basin, except from
18N to 24N east of 30W where NE winds are fresh. Seas are 3-5 ft
north of 19N and west of 55W, and 5-7 ft elsewhere in open waters.
Seas are locally 8 ft NE of the Cabo Verde Islands.
For the forecast W of 55W, the ridge will weaken and sink
southward through early next week as a frontal boundary moves off
the eastern seaboard and stalls NE Florida along about 31N.
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 by early
Sat, bringing a slight increase in winds and seas over those
waters through early Mon.