[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 010952
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
552 AM EDT Sun Oct 1 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 0600 UTC surface analysis and satellite imagery through
0915 UTC.

...SPECIAL FEATURES...
An elongated area of low pressure is noted across the SW North
Atlc waters focused on a 1013 mb low centered near 31N73W with a
cold front extending SW to 28N76W. Farther W...a surface trough
extends from 30N80W SW into a 1012 mb low centered across the
central Florida peninsula near 29N81W. A strong pressure gradient
N of 29N W of 79W is generating near gale to gale force NE to E
winds. The gradient is forecast to relax within 24 hours. See the
latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/
FZNT02 KNHC for more details.

...TROPICAL WAVES...
A tropical wave extends from 07N41W to 21N47W moving W at 10-15
kt. The wave coincides with 700 mb troughing 40W-52W and
continues moving beneath the influence of an upper level low
centered near 17N46W. Given these features...scattered moderate
convection is from 05N-19N between 34W-47W.

A tropical wave extends from 09N73W to 18N71W moving W at 5-10
kt. An upper level low is centered over the northern portion of
the wave axis near 19N72W and continues interacting favorably
with the wave producing scattered moderate convection from 12N-
19N between 67W-76W. A surface trough...fractured energy from the
tropical wave...extends from 20N70W to 25N68W...and now largely is
a surface reflection of the upper level low providing focus for
scattered moderate convection from 19N-23N between 63W-70W. The
upper level low will retrograde westward through Sunday and remain
in a favorable position to produce active convection across
Puerto Rico and Hispaniola through Monday.

...ITCZ/MONSOON TROUGH...
The monsoon trough extends from the African coast near 07N12W to
07N26W. The Intertropical Convergence Zone extends from 07N26W to
08N36W to 08N40W. Scattered moderate convection is from 05N-12N
between 13W-20W...and from 04N-10N between 30W-42W.

...DISCUSSION...

GULF OF MEXICO...
A broad area of lower surface pressure is analyzed across the
entire Gulf this morning focused primarily around an upper level
low centered near 23N87W. While large-scale moderate cyclonic
surface winds prevail...a few surface troughs analyzed across the
basin highlight the areas of active convection and precipitation.
The first surface trough extends from a 1012 mb low centered
across the northern Florida peninsula near 29N81W to the Tampa
Bay region and into the SE Gulf near 26N85W. Moisture and
cloudiness advected northward by the upper level low and the weak
surface troughing are generating isolated showers N of 27N E of
90W...and scattered showers and isolated tstms S of 25N between
82W-88W. Another surface trough is analyzed along the Mexico
coast from 24N98W to 18N94W providing focus for scattered showers
and isolated tstms S of 25N W of 94W. Looking ahead...surface
ridging will begin to build across the SE CONUS by early Monday
strengthening the pressure gradient and increasing E-SE winds
across much of the NE Gulf. By Monday night areal coverage of this
wind field is expected expand and influence the northern two-
thirds of the basin as fresh to strong E-NE winds will prevail.

CARIBBEAN SEA...
Active convection will continue with the tropical wave moving
across the central Caribbean as an upper level low noted on water
vapor imagery over Hispaniola moves W and generally in tandem
with the wave during the next 24 hours. Scattered showers and
tstms are occurring generally between 66W and 77W with these
features. Elsewhere...an upper level low centered over the SE
Gulf of Mexico is generating scattered showers and strong tstms
across the NW Caribbean and portions of Central America N of 14N
W of 80W. This activity spreads westward across southern
Guatemala and southern Mexico...including the adjacent East
Pacific coastal waters. Otherwise...gentle to moderate E-SE trades
will persist through Sunday.

...HISPANIOLA...
Currently the island falls under the influence of an upper level
low centered near 19N72W and a tropical wave moving beneath the
upper level feature. The upper level low will continue moving
westward with the tropical wave and generate scattered showers
and tstms across the region through Sunday.

ATLANTIC OCEAN...
Outside of the influence of the strengthened pressure gradient
across the far NW portion of the SW North Atlc area generating the
near gale to gale force winds...a cold front extends from the
remnants of Maria through 34N50W to 32N56W then becomes stationary
into a 1013 mb low centered near 31N73W. Isolated showers and
tstms are possible within 120 nm either side of the front...and N
of 27N between 65W-75W in association with the elongated area of
low pressure as mentioned in the Special Features section.
Elsewhere...surface ridging prevails across much of the remainder
of the central and eastern Atlc anchored by 1027 mb high centered
E of the Azores near 39N20W.

For additional information please visit
http://www.hurricanes.gov/marine

$$
HUFFMAN
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