AXNT20 KNHC 050609
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
205 AM EDT Wed Aug 05 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 0000 UTC surface analysis and satellite imagery through
The center of Post-Tropical Cyclone ISAIAS, at 05/0600 UTC, is
near 46.1N 72.2W. This position also is about 60 nm/110 km to
the SW of Quebec City, in Canada. ISAIAS is moving NNE, or 020
degrees, 33 knots. The estimated minimum central pressure is
1000 mb. The maximum sustained wind speeds are 40 knots with
gusts to 50 knots. The maximum sustained wind speeds have
decreased to near 40 knots,
with higher gusts, mainly over water to the southeast of the
center. Continued weakening is expected.
The wind speeds are expected to slow down, to less than tropical
storm-force, during the next few hours. The post-tropical
cyclone is expected to dissipate in southeastern Canada, on
Wednesday night or Thursday.
Please read the latest NHC Public Advisory at
https://www.nhc.noaa.gov/text/MIATCPAT4.shtml, and the
https://www.nhc.noaa.gov/text/MIATCMAT4.shtml, for more details.
An Atlantic Ocean tropical wave is along 27W/28W, from 18N
southward, moving W 10 to 15 knots.
Precipitation: any nearby precipitation is in the monsoon trough.
An Atlantic Ocean tropical wave is along 38W/39W, from 19N
southward, moving westward 10 to 15 knots.
Precipitation: any other nearby precipitation is in the monsoon
An Atlantic Ocean tropical wave is along 50W/51W, from 17N
southward, moving westward 15 to 20 knots.
Precipitation: any other nearby precipitation is in the ITCZ.
A Caribbean Sea tropical wave is along 80W/81W, from 20N
southward, moving W 15 knots. An upper level cyclonic
circulation center is about 210 nm to the south of Jamaica.
Upper level cyclonic wind flow covers the Caribbean Sea from 70W
westward. Precipitation: widely scattered moderate to isolated
strong covers the Caribbean Sea from 72W westward.
The monsoon trough passes the coastal sections of Mauritania
near 18N16W, to 16N20W 10N30W, and 08N38W. The ITCZ is along
08N/09N between 40W and 50W, and from 08N52W to 11N62W.
Precipitation: widely scattered moderate to isolated strong is
within 360 nm to south of the monsoon trough and the ITCZ from
58W eastward. Isolated moderate to locally strong is elsewhere
within 400 nm to the north of the monsoon trough and the ITCZ
between 30W and 58W.
GULF OF MEXICO...
Upper level cyclonic wind flow covers the Gulf of Mexico, with a
trough. The trough is supporting a stationary front that is
inland, from northern Georgia to east Texas. Precipitation:
isolated moderate to locally strong was covering the areas from
SE Louisiana to east Texas, at 05/0000 UTC. That precipitation
has been moving southeastward with time, and weakening and
dissipating. Broken to overcast multilayered convective debris
clouds cover the Gulf of Mexico from 27N northward between 87W
A 1015 mb high pressure center is near 28N93W. Broad surface
anticyclonic wind flow spans the entire area.
Light to gentle variable wind will dominate the Gulf of Mexico,
N of 22N, through most of the period, 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 along the
Yucatan Peninsula, associated with a surface trough.
An upper level cyclonic circulation center is about 210 nm to
the south of Jamaica. Upper level cyclonic wind flow covers the
Caribbean Sea from 70W westward. A tropical wave is along
80W/81W, from 19N southward. Precipitation: widely scattered
moderate to isolated strong covers the Caribbean Sea from 72W
A second upper level cyclonic circulation center is between
Dominica and Martinique. A separate area of upper level cyclonic
wind flow covers the rest of the Caribbean Sea. Precipitation:
isolated moderate is from 10N to 20N between 55W and 70W. Upper
level NE wind flow is moving across the Atlantic Ocean, from 20N
to 25N between 50W and 70W. Broken to overcast multilayered
clouds and isolated moderate rainshowers are moving the northern
sections of Puerto Rico and the Dominican Republic, from the
The monsoon trough is along 08N/09N, from Colombia along 74W
westward, beyond southern sections of Costa Rica. Precipitation:
scattered to numerous moderate to strong is in Colombia and in
the eastern Pacific Ocean coastal areas of Colombia from 03N to
09N between 75W and 78W, and from 09N to 10N between 72W and 74W
near the border of Venezuela and Colombia.
The Bermuda High across the W Atlantic Ocean, along with the
eastward extension of the NE Pacific monsoon trough to Colombia,
will support fresh to strong trade winds in the central basin
Wednesday, then extending to the SW Caribbean Sea on Wednesday
night, and continuing through the weekend. Moderate to fresh
winds are expected in the Gulf of Honduras, and in the eastern
Caribbean Sea, during the same time period.
A surface trough passes through SE Georgia and NE Florida, into
the Atlantic Ocean, to 28N74W, and to 28N68W. Precipitation:
isolated moderate is from 28N northward from 77W westward.
A 1016 mb low pressure center is near 32N50W. A dissipating
stationary front extends from the low pressure center to 28N56W.
A surface trough continues from 28N56W to 28N65W. Precipitation:
isolated moderate is from 25N northward between 50W and 70W.
A surface trough is along 38W/39W from 20N to 29N. The trough
has been appearing in the scatterometer wind field for at least
the last 18 hours or so. Precipitation: isolated moderate is
within 120 nm to the east of the surface trough, and within 240
nm to the west of trough, from 20N to 30N.
High pressure in the W Atlantic Ocean extends southwestward, to
the NW waters, and it will persist into the weekend. This will
promote moderate to locally fresh E-SE winds across the Great
Bahama Bank and N of Hispaniola through the weekend. Strong
winds are likely N of Hispaniola at night. A weak low pressure
center will develop in the NE offshore waters tonight, and shift
to the north central waters by Friday, before dissipating during