Tropical Weather Discussion
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AXNT20 KNHC 141722

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1222 PM EST Tue Nov 14 2017

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 1200 UTC surface analysis and satellite imagery through
1715 UTC.


A 1010 mb low pressure center is near 34.5N29W, about 230 nm to
the SSW of the Azores. A surface trough extends S from the low
center to 30N30W to 25N35W. Scattered moderate convection is just
S of the Azores from 34N-37N between 25W-28W. Scattered showers
are elsewhere within 180 nm of the low. The low center is
supported aloft by an upper level low center near 35N29W. This system
has the potential to become a subtropical cyclone during the next
couple of days before upper-level winds become unfavorable.
Regardless of development, this low is expected to produce winds
to near gale force during the next day or two while it moves
slowly northeastward. For additional information on this system,
see High Seas Forecasts issued by Meteo France under WMO header
FQNT50 LFPW and on the web at
meteo-marine/bulletin. This system has a medium chance of
becoming a subtropical cyclone during the next couple of days.


The monsoon trough extends from the African coast near 07N12W to
07N19W. The Intertropical Convergence Zone axis extends from
07N19W to 04N30W to the coast of South America near 03N51W.
Scattered moderate convection is from 02N-06N between 08W-15W.



Radar imagery shows scattered showers over central Florida due to
the tail-end of quasi-stationary front near Melbourne. More
scattered showers are over the Straits of Florida E of 83W.
Elsewhere, scattered showers are over the Bay of Campeche. 10-20
kt NE to E surface winds are over the Gulf of Mexico due to
surface ridging. In the upper levels, a trough is over the Gulf
of Mexico with axis from N Florida to the Yucatan Peninsula.
Strong subsidence is over the Gulf. Expect over the next 48 hours
for surface ridging to build over the Gulf with scattered showers
persisting over the Bay of Campeche.


A surface trough extends over the W Caribbean from 16N88W to
17N83W to include the Gulf of Honduras. Isolated moderate
convection is within 90 nm of the trough. A surface trough extends
from E Cuba near 22N77W to 18N81W. Isolated moderate convection
is within 90 nm of this trough. Further S, a 1007 mb low is along
the coast of Colombia near 11N77W. Numerous strong convection is
from 10N-14N between 76W-79W. Scattered moderate convection is
elsewhere from 09N-15N between 74W-83W. In the upper levels,
upper level diffluence is over the NW Caribbean enhancing
convection. An upper level high is centered over N Colombia near
10N76W. Expect additional convection over the central and SW
Caribbean over the next 48 hours.


Scattered moderate convection is presently over Haiti, and
scattered showers are over the Dominican Republic; mostly due to
upper level diffluence. Expect convection to spread over all of
Hispaniola over the next 24 hours. Convection will be heaviest in
the afternoon and evening hours during maximum heating. Localized
flooding and life-threatening mud slides are also possible over
the next 48 hours.


A quasi-stationary front is over the W Atlantic from 31N73W to
Melbourne Florida near 28N80W. Isolated moderate convection is
within 45 nm of the front. A prefrontal front extends from 30N70W
to the central Bahamas near 25N75W. Scattered moderate convection
is N of 25N between 62W-73W. A 1021 mb high is centered over the
central Atlantic near 30N49W. A 1010 mb low is over the E Atlantic
S of the Azores. See above. In addition a surface trough
is over the tropical Atlantic from 24N28W to 16N30W. Scattered
showers are within 180 nm of the trough. Of note in the upper
levels, an upper level trough is over the far W Atlantic
supporting the front. A large upper level low is centered over
the E Atlantic near 35N29W with a trough axis extending SW to
20N40W. Upper level diffluence is E of this trough axis to the
coast of W Africa.

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