[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 231805
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT THU OCT 23 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
1745 UTC.

...TROPICAL WAVES...

A TROPICAL WAVE IS OVER THE CENTRAL ATLC WITH AXIS EXTENDING FROM
12N30W TO 3N30W...MOVING W AT 20 KT. SSMI TPW...WATER VAPOR AND
GOES-R IMAGERY/PRODUCTS INDICATE THE WAVE IS EMBEDDED IN A DEEP
LAYER ENVIRONMENT. THE WAVE COINCIDES WITH A DIFFLUENT
ENVIRONMENT AT THE UPPER LEVELS THAT IS MAINTAINING SCATTERED
MODERATE CONVECTION AND ISOLATED TSTMS FROM 3N-12N BETWEEN 23W-
33W.

A TROPICAL WAVE IS OVER THE ATLC WATERS WITH AXIS EXTENDING FROM
13N40W TO 6N41W...MOVING W AT 10-15 KT. THE IMMEDIATE WAVE
ENVIRONMENT IS ASSOCIATED WITH SHALLOW MODERATE MOISTURE THAT
ENHANCES ISOLATED SHOWERS WITHIN 200 NM EITHER SIDE OF THE AXIS.
THE WAVE IS EMBEDDED IN A STRONG DEEP LAYER WIND SHEAR
ENVIRONMENT THAT INHIBITS FURTHER CONVECTION.

A TROPICAL WAVE IS ENTERING THE EASTERN CARIBBEAN SEA WITH AXIS
EXTENDING FROM 17N59W TO 9N62W...MOVING W AT 10 KT. LOW TO
MIDDLE LEVEL MODERATE TO HIGH MOISTURE ALONG WITH A DIFFLUENT
ENVIRONMENT ALOFT SUPPORT SCATTERED MODERATE CONVECTION AND
ISOLATED TSTMS S OF 14N BETWEEN 57W-66W. IN THE NORTHERN REGION
OF THE WAVE...BOTH DRY AIR ALOFT ALONG WITH DEEP LAYER
ENVIRONMENTAL WIND SHEAR SUPPRESS THE THE DEVELOPMENT OF DEEP
CONVECTION. ISOLATED SHOWERS AND TSTMS ARE WITHIN 100 NM EITHER
SIDE OF THE WAVE AXIS N OF 14N.

...THE ITCZ/THE MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS AFRICA TO THE E TROPICAL ATLC
NEAR 11N16W AND CONTINUES TO 9N22W. THE ITCZ EXTENDS FROM 9N23W
TO 7N29W...IT RESUMES W OF A TROPICAL WAVE FROM 6N32W TO
7N38W...THEN AGAIN W OF A SECOND TROPICAL WAVE FROM 7N43W TO 7N52W.
BESIDES THE CONVECTION ASSOCIATED WITH THE TROPICAL
WAVES...SCATTERED MODERATE CONVECTION IS FROM 2N-7N BETWEEN 33W-
39W AND FROM 6N-9N BETWEEN 50W-53W.

...DISCUSSION...

GULF OF MEXICO...

A MIDDLE-LEVEL CYCLONE CENTERED S OF MASSACHUSETTS EXTENDS A
TROUGH AXIS SW ACROSS THE SW N ATLC...THE FLORIDA PENINSULA AND
THE YUCATAN PENINSULA...THUS SUPPORTING A COLD FRONT ANALYZED IN
THE GULF ALONG 25N81W TO 24N87W TO 22N91W WHERE IT TRANSITIONS
TO A STATIONARY FRONT TO THE BAY OF CAMPECHE NEAR 18N94W. STRONG
DEEP LAYER ENVIRONMENTAL SHEAR AND DRY AIR INHIBITS THE
DEVELOPMENT OF CONVECTION N OF THE FRONTAL BOUNDARY. IN THE SW
GULF...A MODERATE MOIST ENVIRONMENT SUPPORT ISOLATED SHOWERS AND
TSTMS S OF 21N W OF THE STATIONARY FRONT. AHEAD OF THE COLD
FRONT...THE TROUGH ALOFT SUPPORT A 1008 MB LOW IN THE YUCATAN
CHANNEL NEAR 22N86W. A SURFACE TROUGH EXTENDS FROM THE STRAITS
OF FLORIDA SW TO THE LOW...THEN SW TO A 1009 MB LOW IN THE
YUCATAN PENINSULA. A DIFFLUENT ENVIRONMENT ALOFT GENERATED BY A
BROAD RIDGE CENTERED OVER THE WESTERN CARIBBEAN SUSTAINS A
CLUSTER OF MODERATE TO ISOLATED STRONG CONVECTION FROM 18N-24N
BETWEEN 81W-87W...INCLUDING WESTERN CUBA. THE COLD FRONT WILL
MOVE INTO THE NW CARIBBEAN BY FRIDAY MORNING WHILE THE LOW
DRIFTS NE TO W OF ANDROS ISLAND.

CARIBBEAN SEA...

A MIDDLE LEVEL TROUGH EXTENDING SW FROM A CYCLONIC CIRCULATION S
OF MASSACHUSETTS SUPPORTS A 1008 MB LOW OVER THE YUCATAN
CHANNEL. LOW LEVEL MOISTURE CONVERGENCE OVER THE NW CARIBBEAN
ALONG A DIFFLUENT ENVIRONMENT ALOFT GENERATED BY A BROAD RIDGE
SUPPORT A CLUSTER OF MODERATE TO ISOLATED STRONG CONVECTION AND
TSTMS FROM 18N-24N BETWEEN 81W-87W. SCATTERED MODERATE
CONVECTION AND TSTMS EXTEND FURTHER EAST N OF 17N BETWEEN 75W-
80W. A TROPICAL WAVE IS MOVING ACROSS THE LESSER ANTILLES. SEE
TROPICAL WAVES SECTION ABOVE. DEEP LAYER DRY AIR AND STRONG
ENVIRONMENTAL SHEAR SUPPORT FAIR WEATHER ELSEWHERE. A COLD FRONT
EXTENDING ACROSS THE SOUTHERN GULF WILL ENTER THE NW CARIBBEAN
BY FRIDAY MORNING...STALLING ALONG CENTRAL CUBA SATURDAY MORNING.

HISPANIOLA...

CURRENTLY DEEP LAYER DRY AIR AND STRONG SHEAR ACROSS THE ISLAND
SUPPORT FAIR WEATHER. MODEL GUIDANCE INDICATE THAT SIMILAR
CONDITIONS ARE LIKELY TO PERSIST THROUGH SATURDAY MORNING.

ATLANTIC OCEAN...

A MIDDLE-LEVEL CYCLONE CENTERED S OF MASSACHUSETTS EXTENDS A
TROUGH AXIS SW ACROSS THE SW N ATLC...THE FLORIDA PENINSULA AND
THE YUCATAN PENINSULA...THUS SUPPORTING A COLD FRONT ANALYZED
FROM 30N66W SW TO 27N73W TO THE FLORIDA STRAITS NEAR
25N81W...THEN ACROSS THE SOUTHERN GULF. SCATTERED SHOWERS ARE
WITHIN 360 NM AHEAD OF THE FRONT WHILE ISOLATED SHOWERS ARE
WITHIN 100 NM N OF THE FRONT. SW OF THE AZORES ISLANDS A 1008 MB
LOW EXTENDS A TROUGH INTO THE AREA OF DISCUSSION ALONG 30N30W TO
25N33W WITH NO CONVECTION ASSOCIATED WITH IT. WEAK RIDGING AND
FAIR WEATHER DOMINATE ELSEWHERE N OF 18N.

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

$$
NR


This weather bulletin was brought to you by:
www.nashvilleweather.net