AXNT20 KNHC 061030
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
630 AM EDT Thu Aug 6 2020
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 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.
Based on 0600 UTC surface analysis and satellite imagery through
An Atlantic Ocean tropical wave is along 35W, from 18N southward,
moving W 15 knots. Dry and stable Saharan air dominates the wave
environment north of 14N. Scattered moderate to strong convection
is seen along and south of the monsoon trough from 05N to 10N
between 27W and 36W.
An Atlantic Ocean tropical wave is along 45W, from 15N southward,
moving westward 15 knots. Widely scattered moderate convection is
seen from 06.5N to 11.5N between 43W and 52W.
An Atlantic Ocean tropical wave is along 57W, from 17N southward,
moving westward 10 to 15 knots. Scattered moderate convection is
seen from 13N to 16.5N between 54W and 57W, while widely scattered
moderate convection is ahead of the wave from 09N to 13N between
57W and 60W.
A Caribbean Sea tropical wave is along 88W, from 19N southward,
moving westward 15-20 knots. Middle to upper level cyclonic
wind flow across most of the Gulf of Mexico is combining with a
second middle to upper level low across the Caribbean southeast
of Jamaica to enhancing strong associated convection with this
wave covers the Caribbean Sea from Haiti westward. Precipitation:.
Scattered to numerous moderate to strong convection extends from
the Yucatan Channel along 20N south and southeastward across the
Gulf of Honduras, the southeastward to coastal Colombia. Clusters
of strong convection with tops to -80 deg C and lower are found
offshore of Panama and Colombia.
The monsoon trough passes the coastal sections of Mauritania near
17N16W to 10N29W to 10N48W. The ITCZ continues along 10N between
49W and 63W. Scattered moderate isolated strong convection is seen
within 210 nm southeast of the monsoon trough between 19W and
25W. Elsewhere convection is described with tropical waves above.
GULF OF MEXICO...
Broad upper level cyclonic wind flow covers the Gulf of Mexico,
with the cyclonic center over the east central Gulf. This is
producing generally stable atmospheric conditions across much of
the Gulf, except for scattered moderate convection across the NE
Gulf north of 25.5N extending into the Big Bend region. A few
clusters of moderate convection are seen offshore of the SE
Louisiana coast and just south of Mobile Bay, to the south of a
stalled frontal boundary over coastal sections from south
Louisiana to the western Florida Panhandle. A cluster of moderate
convection lingers across the central Bay of Campeche south of
A weak 1015 mb high pressure center near 27N92W has collapsed
leaving glight to gentle anticyclonic flow at the surface extending
from western Florida to SE Texas.
Light to gentle variable wind will dominate the Gulf waters
through Mon night as a weak surface ridge prevails. Moderate to
fresh NE to E winds are expected at night in the eastern half of
the Bay of Campeche and the adjacent Yucatan peninsula waters
associated with a surface trough.
An upper level trough extends from the central Atlantic
southwestward to the eastern Caribbean and then westward to an
upper level low center near 15N75W. Stable conditions generally
prevail underneath of this troughing, except for very active
convection described above associated with the tropical wave
across the western Caribbean along 88W. Fresh to strong tradewinds
dominate the central Caribbean south of 17N, strongest along the
coast of Colombia and the Gulf of Venezuela. Seas of 7-10 ft are
found across this area. Elsewhere moderate trades prevail across
The pressure gradient between weak high pressure over the SW N
Atlantic and the eastward extension of the NE Pacific monsoon
trough to Colombia will support fresh to strong tradewinds across
the central basin through Fri. Strong trades will increase and
expand across central portions over the weekend with the passage
of a pair of tropical waves. Near gale-force winds are expected
along the Colombia coastal waters and the Gulf of Venezuela Sat
and Sun nights. Otherwise, moderate to fresh easterly winds are
expected in the Gulf of Honduras and in the E Caribbean through
A lingering surface trough extends into the area along 31N51W then
meanders southwest and then northwestward to a 1016 mb low
pressure center near 29N64W. Scattered moderate convection is seen
within 120 nm either side of the trough between 63W and 72W.
Surface high pressure is found on either side of this trough, with
a 1022 mb high near 36N61W, and weak ridge centered across the
central Atlantic extends W-SW to the south of the trough. Moderate
to locally fresh tradewinds prevail across the Tropical Atlantic
south of 20N were seas are 5-7 ft.
The surface trough will linger across the waters south of Bermuda
through Sat before gradually shifting east of the offshore waters
Sun through Mon. Elsewhere high pressure on either side of the
trough will support light to gentle variable winds, except south
of 23N, where moderate to fresh easterly winds will dominate the
waters from the Great Bahama Bank to the waters north of