[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 252348
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT SUN OCT 25 2009

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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND
RADAR.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2315 UTC.

...TROPICAL WAVES...

TROPICAL WAVE REMAINS TILTED FROM 18N48W TO 10N50W MOVING NW
10-15 KT. WAVE REMAINS EMBEDDED WITHIN A MAXIMUM IN TOTAL
PRECIPITABLE WATER. ISOLATED SHOWERS ARE FROM 16N18N BETWEEN
47W-51W.

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 15N15W 10N27W 10N46W 7N60W. A
SHORT SURFACE TROUGH EXTENDS ALONG 55W FROM 11N-14N WITH
ISOLATED SHOWERS FROM 11N-14N BETWEEN 52W-57W. SCATTERED
MODERATE/STRONG CONVECTION IS WITHIN 250 NM S OF THE ITCZ FROM
23W-30W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG
CONVECTION ARE FROM 4N-13N BETWEEN 37W-47W.

...DISCUSSION...

GULF OF MEXICO...
THE FRONTAL BOUNDARY IS BEGINNING TO MOVE N OVER THE SE GULF
EXTENDING ACROSS FLORIDA NEAR MIAMI JUST N OF THE FLORIDA KEYS
TO 23N86W WITH ISOLATED SHOWERS WITHIN 45 NM N OF THE FRONT. A
DEEP LAYERED TROUGH IS MOVING ACROSS THE CENTRAL PLAIN STATES TO
OVER THE UPPER MISSISSIPPI VALLEY WITH THE COLD FRONT WELL
INLAND OVER OKLAHOMA AND TEXAS. TROPICAL MOISTURE CONTINUES TO
BE DRAWN NE ACROSS MEXICO AND THE GULF WITH SCATTERED SHOWERS/
ISOLATED THUNDERSTORMS OVER THE W GULF N OF 20N W OF 90W. THE
NEXT COLD FRONT IS EXPECTED TO MOVE OFF THE TEXAS COAST MON
NIGHT.

CARIBBEAN SEA...
A SERIES OF SURFACE TROUGHS ARE PLAGUING THE W CARIBBEAN...ONE
ALONG THE COAST OF THE YUCATAN PENINSULA S OF 20N TO JUST INLAND
OVER HONDURAS...A SECOND FROM JUST OFF THE COAST OF COSTA RICA
TO ALONG THE COAST OF NICARAGUA...AND A THIRD FROM JUST SW OF
THE CAYMAN ISLANDS TO 14N80W. ALL OF THE TROUGHS ARE WEAK WITH
NO SIGNIFICANT ACTIVITY ASSOCIATED WITH THEM. THE ELONGATED
UPPER LOW IS CENTERED OVER CUBA NEAR 22N78W WITH THE UPPER
TROUGH EXTENDING SW TO NEAR 15N74W GENERATING SCATTERED SHOWERS/
ISOLATED THUNDERSTORMS WITHIN 90/120 NM OF LINE FROM 14N77W TO
OVER CUBA NEAR 23N81W. AN UPPER TROUGH OVER THE TROPICAL ATLC
EXTENDS W OVER THE E CARIBBEAN WITH DRY AIR AND MODERATE/STRONG
SUBSIDENCE COVERING THE E CARIBBEAN AND THUS CLEAR SKIES FOR
THAT AREA.

ATLANTIC OCEAN...
THE REMNANT STATIONARY FRONTAL BOUNDARY ENTERS THE FAR W ATLC
NEAR 32N79W S ALONG 29N79W TO OVER FLORIDA NEAR MIAMI GENERATING
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 60 NM EITHER
SIDE OF THE FRONT N OF 28N. THE ELONGATED UPPER LOW CENTERED
OVER CUBA NEAR 22N78W EXTENDS N TO 27N78W. AN UPPER HIGH IS JUST
TO THE E ANCHORED NEAR BERMUDA PROVIDING DIFFLUENCE ALOFT TO
ENHANCE THE ACTIVITY ASSOCIATED WITH THE FRONT AND GENERATE
SCATTERED SHOWERS WITH POSSIBLE ISOLATED THUNDERSTORMS S OF 24N
FROM 72W-78W. LARGE AREA OF STRONG SUBSIDENCE AND DRY STABLE AIR
IS ACROSS MOST OF THE CENTRAL ATLC THUS LIMITING SHOWER ACTIVITY.
A SURFACE RIDGE IS BUILDING S OVER THE REMAINDER OF THE W AND
INTO THE CENTRAL ATLC W OF 50W ANCHORED BY A 1027 MB HIGH WELL N
OF THE REGION. BROAD UPPER TROUGH IS OVER THE E/CENTRAL ATLC N
OF 25N FROM 25W-50W SUPPORTING A COLD FRONT ENTERING THE REGION
NEAR 32N30W EXTENDING SW ALONG 28N40W TO 28N49W WITH ISOLATED
SHOWERS WITHIN 60 NM SE OF THE COLD FRONT. A PREFRONTAL SURFACE
TROUGH EXTENDS FROM 31N25W SW TO 26N31W WITH SCATTERED SHOWERS N
OF 29N FROM 25W-27W.

$$
WALLACE





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