[Tropical] Tropical Weather Discussion

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AXNT20 KNHC 241753
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT WED SEP 24 2014

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.

...TROPICAL WAVES...
TROPICAL WAVE EXTENDS FROM 14N31W TO 25N30W MOVING W-NW AT 10
KT. A 1014 MB LOW IS CENTERED ALONG THE WAVE AXIS NEAR 19N THAT
HAS PULLED NORTH OF THE INFLUENCE OF THE MONSOON TROUGH ZONE.
THE WAVE COINCIDES WITH A BROAD 700 MB LOW CENTERED NEAR 18N33W
THAT INFLUENCES THE EASTERN ATLC FROM 13N-25N BETWEEN 27W-41W.
WEST-NORTHWESTERLY SHEAR IS CONTINUING TO IMPACT CONVECTIVE
DEVELOPMENT WITH ONLY ISOLATED MODERATE CONVECTION OCCURRING
WELL TO THE EAST OF THE LOW AND WAVE FROM 15N-21N BETWEEN 25W-
28W...AND FROM 21N-24N BETWEEN 26W-31W.

TROPICAL WAVE EXTENDS FROM 14N55W TO 22N53W MOVING W AT 10-15
KT. THE WAVE REMAINS RELATIVELY WEAK AND COINCIDES WITH LOW TO
MIDDLE LEVEL TROUGHING BETWEEN 49W-57W. THE WAVE IS BEGINNING TO
MOVE BENEATH THE INFLUENCE OF SOUTHWESTERLY MIDDLE TO UPPER
LEVEL FLOW ON THE SOUTHERN PERIPHERY OF AN UPPER LEVEL LOW
CENTERED NEAR 26N57W WHICH IS PROVIDING AN OVERALL HIGH WIND
SHEAR ENVIRONMENT AND AN OVERALL LACK OF ANY SIGNIFICANT DEEP
CONVECTION AT THIS TIME.

TROPICAL WAVE EXTENDS FROM 12N73W TO 21N74W MOVING W AT 15 KT.
GENERALLY SOUTHEASTERLY FLOW ALOFT IS NOTED OVER THE REGION OF
THE WAVE WHICH CONTINUES TO STRETCH LOW TO MID-LEVEL ENERGY
NORTHWARD AROUND THE SOUTHWESTERN PERIPHERY OF A MID-LEVEL RIDGE
CENTERED OVER THE SW NORTH ATLC NEAR 33N67W. A PORTION OF THIS
ENERGY IS ANALYZED AS A SURFACE TROUGH TO THE NORTH OF THE WAVE
FROM THE SE BAHAMAS NEAR 22N74W TO 28N73W. LOW-LEVEL MOISTURE
CONVERGENCE REMAINS MAXIMIZED TO THE EAST OF THE WAVE AXIS WITH
WIDELY SCATTERED MODERATE CONVECTION FROM 10N-18N BETWEEN 65W-
75W...AND FROM 24N-27N BETWEEN 71W-74W.

TROPICAL WAVE EXTENDS FROM 10N87W TO 21N91W MOVING W AT 10-15
KT. THE WAVE CONTINUES TO MOVE BENEATH THE BASE OF AN UPPER
LEVEL TROUGH WITH AXIS ALONG 90W OVER THE CENTRAL GULF OF
MEXICO...SOUTHERN MEXICO...AND GUATEMALA. WHILE 700 MB TROUGHING
EXTENDS NORTHWARD OVER CENTRAL AMERICA AND PORTIONS OF THE SW
GULF OF MEXICO...THE MAIN MID-LEVEL CIRCULATION CENTER ALOFT
LIES WEST OF COSTA RICA IN THE EAST PACIFIC REGION NEAR 08N87W.
NO SIGNIFICANT DEEP CONVECTION IS ASSOCIATED WITH THE WAVE AT
THIS TIME.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 18N16W TO
12N22W TO 12N30W TO 10N35W TO 11N39W. THE INTERTROPICAL
CONVERGENCE ZONE AXIS EXTENDS FROM 11N39W INTO A 1015 MB LOW
NEAR 14N45W TO 12N53W. ASIDE FROM CONVECTION OCCURRING WITH THE
TROPICAL WAVES...SCATTERED MODERATE CONVECTION IS FROM 03N-13N
BETWEEN 18W-33W...AND FROM 14N-17N BETWEEN 42W-46W.

...DISCUSSION...

GULF OF MEXICO...
A MIDDLE TO UPPER LEVEL LOW IS NOTED ON WATER VAPOR IMAGERY
CENTERED OVER THE CAROLINAS THIS AFTERNOON THAT EXTENDS A TROUGH
AXIS SW TO A BASE OVER SOUTHERN MEXICO AND GUATEMALA NEAR
17N91W. THE UPPER LEVEL TROUGHING SUPPORTS A STATIONARY FRONT
ANALYZED ACROSS THE FLORIDA PENINSULA FROM 28N80W TO 26N82W AND
INTO THE GULF WATERS TO 26N90W TO 22N97W. LOW-LEVEL MOISTURE
CONVERGENCE IS MAXIMIZED ALONG THE FRONT GENERATING SCATTERED
SHOWERS AND ISOLATED TSTMS WITHIN 120 NM EITHER SIDE OF THE
BOUNDARY. OTHERWISE...TO THE NORTH OF THE FRONT ACROSS THE GULF
COAST AND COASTAL WATERS...HIGH PRESSURE REMAINS IN CONTROL
PROVIDING MOSTLY CLOUDY SKIES AND GENERALLY EAST-NORTHEASTERLY
WINDS IN THE RANGE OF 10 TO 20 KT.

CARIBBEAN SEA...
AN UPPER LEVEL TROUGH AXIS EXTENDS ALONG 90W OVER THE YUCATAN
PENINSULA AND PORTIONS OF CENTRAL AMERICA THAT SUPPORTS A
RELATIVELY DIFFLUENT ENVIRONMENT ACROSS THE FAR WESTERN
CARIBBEAN AND NW CARIBBEAN THIS AFTERNOON. FOCUSED ON AN UPPER
LEVEL ANTICYCLONIC CIRCULATION CENTERED NEAR 18N83W...SCATTERED
SHOWERS AND TSTMS ARE OCCURRING FROM 10N-23N BETWEEN 79W-88W...
INCLUDING PORTIONS OF NICARAGUA AND HONDURAS. THIS CONVECTION
LIES LARGELY ON THE WESTERN PERIPHERY OF A TROPICAL WAVE
ANALYZED WEST OF THE BASIN ALONG 90W. TO THE EAST...ANOTHER
TROPICAL WAVE LIES ALONG 74W WITH A PORTION OF THE ENERGY
FRACTURED NORTH OF THE WAVE ACROSS THE SW NORTH ATLC REGION. LOW-
LEVEL MOISTURE CONVERGENCE IS MAXIMIZED EAST OF THE WAVE AXIS
GENERATING SCATTERED SHOWERS AND TSTMS FROM 11N-18N BETWEEN 64W-
75W. OTHERWISE...ANOTHER WEAK TROPICAL WAVE LIES TO THE EAST OF
THE LESSER ANTILLES ALONG 54W AND IS EXPECTED TO BEGIN IMPACTING
THE BASIN THURSDAY INTO FRIDAY WITH INCREASED CLOUDINESS AND
PRECIPITATION.

...HISPANIOLA...
CURRENTLY...A TROPICAL WAVE LIES ALONG 74W BRINGING SCATTERED
SHOWERS AND TSTMS TO THE CARIBBEAN COASTAL WATERS S OF 18N AT
THIS TIME. CONTINUED LOW-LEVEL MOISTURE ADVECTION THROUGH THIS
EVENING INTO THURSDAY ACROSS THE ISLAND WILL PROVIDE A FAVORABLE
ENVIRONMENT FOR CONVECTIVE PRECIPITATION. AS THE TROPICAL WAVE
MOVES WEST OF THE REGION...CONDITIONS ARE EXPECTED TO IMPROVE
SLIGHTLY FRIDAY INTO SATURDAY.

ATLANTIC OCEAN...
A MIDDLE TO UPPER LEVEL LOW IS CENTERED OVER THE MID-ATLC STATES
NEAR 37N82W WITH TROUGHING THAT EXTENDS SW OVER THE CENTRAL GULF
OF MEXICO THIS AFTERNOON. THE LOW AND TROUGHING SUPPORT A 1016
MB LOW CENTERED NEAR 32N79W AND AN ASSOCIATED STATIONARY FRONT
EXTENDING FROM THE LOW CENTER TO THE FLORIDA PENINSULA NEAR
28N80W. PLENTY OF LOW-LEVEL MOISTURE CONVERGENCE ALONG THE FRONT
COINCIDES WITH AN AREA OF MAXIMUM MIDDLE TO UPPER LEVEL
DIFFLUENCE TO THE EAST OF THE UPPER LEVEL TROUGH THAT IS
GENERATING SCATTERED SHOWERS AND TSTMS N OF 22N BETWEEN 76W-81W.
TO THE SOUTHEAST OF THE FRONTAL AREA...ENERGY ASSOCIATED WITH
THE TROPICAL WAVE ACROSS THE CENTRAL CARIBBEAN SEA HAS FRACTURED
NORTH AND IS ANALYZED AS A SURFACE TROUGH FROM 22N74W TO 28N73W.
SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING FROM 22N-28N
BETWEEN 70W-76W. TO THE EAST...A BROAD ELONGATED UPPER LEVEL LOW
IS CENTERED NEAR 25N58W THAT SUPPORTS A BROAD AREA OF CLOUDINESS
WITH EMBEDDED ISOLATED SHOWERS AND TSTMS OCCURRING FROM 15N-27N
BETWEEN 51W-63W. OTHERWISE...SURFACE RIDGING INFLUENCES THE
REMAINDER OF THE CENTRAL AND EASTERN ATLC N OF 23N WITH THE
EXCEPTION OF A SHEAR LINE ANALYZED FROM 29N29W TO 28N45W. WHILE
ISOLATED SHOWER ACTIVITY IN THE VICINITY OF THE SHEAR LINE
REMAINS LIMITED...EARLIER MORNING ASCAT PASSES AROUND 23/1120
UTC AND 23/1212 UTC INDICATED STRONGER NORTHEAST WINDS NORTH OF
THE AXIS IN THE RANGE OF 20 TO 25 KT.

FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$
HUFFMAN


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