Tropical Weather Discussion

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Tropical Weather Discussion (NHC/TPC):
NWS National Hurricane Center Miami FL
1245 AM EST Thu Feb 23 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 0000 UTC surface analysis and satellite imagery through 
0530 UTC.

A 990 mb area of low pressure across the central North Atlc 
extends a cold front into the discussion area near 32N45W. The 
front continues SW to 26N50W to 21N57W then stationary to 19N67W.
Near gale to gale force SW winds are occurring N of 28N within 
180 nm E of the front. The gale force conditions are expected to 
move N of the area by 23/0600 UTC. See latest NWS High Seas 
Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more 

A broad area of low pressure focused on a 1002 mb centered across
the southern Florida peninsula is producing near gale to gale
force SE winds from 26N to 29N between 76W and 80W. These gale
force conditions are expected to persist off the coast of Florida
in the SW North Atlc waters through 25/0000 UTC. See latest NWS 
High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC 
for more details.

The Monsoon Trough extends from the African coast near 07N12W to 
04N16W. The Intertropical Convergence Zone axis extends from 
04N16W to 01N23W to the Equator near 35W. Scattered moderate and
isolated strong convection is from 04N-09N between 03W-12W.
Isolated moderate convection is within 90 nm either side of the
ITCZ axis between 14W-29W.


The broad surface low mentioned in the Special Features section is
supported aloft by an upper level trough with axis along 81W and a
vigorous mid-level low and associated energy centered over the
southern Florida peninsula this evening. The associated cold front
extends from the 1002 mb low near 27N81W to western Cuba near
23N81W and into the NW Caribbean Sea. While most of the 
precipitation is occurring across the Florida Straits and across 
eastern portions of the Florida peninsula into the SW North Atlc 
waters...a few lingering isolated showers are occurring E of 87W.
Otherwise...the remainder of the basin generally W of 90W is under
the influence of weak high pressure anchored by a 1013 mb high
centered across the SW Gulf near 20N93W. Light to gentle
anticyclonic winds prevail across the western Gulf this evening 
and are expected to become more southerly by Thursday night into
Friday as low pressure develops across the central CONUS. The next
cold front is forecast to emerge off the Texas and Louisiana
coasts Friday night.

Most of the Caribbean remains under the influence of dry and
relatively stable west-northwesterly flow aloft. A mid-level low
and associated energy remains across the Florida peninsula and
Florida Straits this evening supporting a cold front extending
across western Cuba and into the NW Caribbean waters from 22N81W
to 19N85W. A pre-frontal surface trough is also analyzed from
central Cuba near 22N78W to northern Nicaragua near 14N85W.
Isolated showers and possible isolated tstms are noted within 180
nm E of the surface trough while isolated showers are possible N
of 18N W of 80W in association with the cold front. Moderate to
fresh W-NW winds are occurring in wake of the front which are
expected to weaken gradually through Thursday as the front
progresses eastward as dissipates across the central waters
Thursday night into Friday. Farther east...a stationary front
remains analyzed N of the Leeward Islands and Puerto Rico tonight
with isolated showers occurring N of 16N E of 66W. The remainder
of the basin is under mostly fair skies and relatively tranquil
conditions as the overall trade wind flow is disrupted with the
presence of the frontal systems in the vicinity. A more normal
trade wind synoptic pattern is expected by Saturday night into 
Isolated showers are expected an approaching pre-frontal surface
trough and cold front increase cloudiness and probability of 
convective precipitation through Thursday. The front will reach
the Windward Passage by Thursday night and gradually weaken as the
low pressure system associated with the front moves N-NE Friday
into Saturday.

A broad area of low pressure is analyzed across the Florida
peninsula and eastern Gulf of Mexico that stretches influence
eastward across the much of the SW North Atlc W of 70W this
evening. In addition to the developing area of near gale to gale
force winds expected with the low as it tracks eastward... 
scattered to numerous showers and isolated tstms are occurring 
across a large area N of 77W W of 70W. The low is expected to be
slow to move E-NE and N of the discussion area by Saturday.
Farther east...a middle to upper level low is centered across the
central North Atlc near 40N50W that supports the Special Features
990 mb low centered near 36N52W and the associated cold front 
producing the near gale to gale force conditions. Scattered 
showers and tstms are occurring E of the front and E of a surface 
trough from 23N51W to 13N57W. The convection remains generally N 
of 13N between 38W-53W. Finally...the remainder of the eastern 
Atlc is under the influence of a surface ridge anchored by a 1029
mb high centered S of the Azores near 37W29W.

For additional information please visit

Graphical representation of waves, etc. on this image (NCEP/OPC) [more].
Various tropical satellite imagery available here

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