[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 221150
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT MON OCT 22 2012

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
1015 UTC.

...SPECIAL FEATURES...

THE 1004 MB LOW REMAINS IN THE CENTRAL CARIBBEAN NEAR 14N78W.
THE TOTAL PRECIPITABLE WATER IMAGERY INDICATES A LARGE AREA OF
DEEP MOISTURE REMAINS OVER THE CENTRAL CARIBBEAN. CLUSTERS OF
SCATTERED MODERATE/STRONG CONVECTION ARE FROM 11N-17N BETWEEN
75W-80W. ENVIRONMENTAL CONDITIONS ARE GRADUALLY BECOMING MORE
CONDUCIVE FOR A TROPICAL DEPRESSION TO FORM DURING THE NEXT DAY
OR SO. THIS SYSTEM HAS A HIGH CHANCE OF BECOMING A TROPICAL
CYCLONE DURING THE NEXT 48 HOURS AS IT REMAINS NEARLY STATIONARY
WELL TO THE SOUTH OF JAMAICA TODAY. HEAVY RAINS FROM THIS
DISTURBANCE ARE LIKELY TO SPREAD OVER JAMAICA...HISPANIOLA...
AND EASTERN CUBA DURING THE NEXT SEVERAL DAYS. THESE RAINS COULD
PRODUCE LIFE-THREATENING FLASH FLOODS AND MUDSLIDES...ESPECIALLY
IN AREAS OF HIGH TERRAIN.

THE 1011 MB LOW REMAINS IN THE CENTRAL ATLC NEAR 21N52W. THE
TOTAL PRECIPITABLE WATER IMAGERY INDICATES A SMALL AREA OF DEEP
MOISTURE SURROUNDING THE LOW CENTER. AN UPPER LOW IS SUPPORTING
THE SURFACE LOW CENTERED NEAR 22N48W. CLUSTERS OF SCATTERED
MODERATE/ISOLATED STRONG CONVECTION ARE 19N-26N BETWEEN 47W-54W.
ENVIRONMENTAL CONDITIONS ARE EXPECTED TO BE CONDUCIVE FOR SOME
DEVELOPMENT BEFORE UPPER-LEVEL WINDS BECOME LESS FAVORABLE ON
TUESDAY. THIS SYSTEM HAS A MEDIUM CHANCE OF BECOMING A TROPICAL
CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES NORTHWARD TO AT
5-10 KT.

...TROPICAL WAVES...

TROPICAL WAVE IS ANALYZED FROM 14N21W TO 9N22W MOVING W NEAR 10
KT. MID LEVEL CYCLONIC CIRCULATION IS OBSERVED ON SATELLITE
IMAGERY. NO ASSOCIATED DEEP CONVECTION.

TROPICAL WAVE IN THE CENTRAL TROPICAL ATLC IS ANALYZED FROM
13N38W TO 9N40W MOVING SW NEAR 10 KT. WEAK LOW LEVEL CYCLONIC
CIRCULATION IS OBSERVED ON SATELLITE IMAGERY. SCATTERED MODERATE
CONVECTION IS WITHIN WITHIN 90 NM OF THE WAVE BETWEEN 10N-12N.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS W AFRICA INTO THE E TROPICAL
ATLC NEAR 10N16W ALONG 7N19W THEN S OF THE E TROPICAL WAVE
CONTINUING ALONG 11N32W TO 10N38W. THE ITCZ IS NOT EVIDENT IN
THE ATLC BASIN. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION
ARE FROM 3N-8N BETWEEN 7W-16W INCLUDING THE COAST OF W AFRICA.
CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE
FROM 6N-12N BETWEEN 37W-35W. CLUSTERS OF SCATTERED MODERATE
CONVECTION ARE FROM 10N-13N E OF 19W TO THE COAST OF W AFRICA.

...DISCUSSION...

GULF OF MEXICO...
A BROAD UPPER RIDGE EXTENDS FROM SW MEXICO OVER TEXAS GIVING THE
GULF NW FLOW ALOFT WITH DRY CONTINENTAL AIR IN PLACE OVER THE
GULF. A BROAD SURFACE RIDGE DOMINATES THE GULF TODAY ANCHORED BY
A 1022 MB HIGH OVER GEORGIA AND A 1024 MB HIGH OVER WEST
VIRGINIA. MODERATE RETURN FLOW REMAINS OVER THE NW GULF. THE
FRONT IN THE W ATLC DISSIPATES OVER W CUBA NEAR 22N81W
GENERATING CLUSTERS OF ISOLATED SHOWERS AND POSSIBLE ISOLATED
THUNDERSTORMS ALONG THE IMMEDIATE COAST OF CUBA E OF 82W.
ISOLATED SHOWERS/THUNDERSTORMS ARE ALSO OVER THE E BAY OF
CAMPECHE S OF 21N BETWEEN 91W-94W LEAVING THE REMAINDER OF THE
GULF WITH REMARKABLY CLEAR SKIES THIS MORNING. WINDS WILL
INCREASE ACROSS THE SE GULF BY TUE BETWEEN SURFACE RIDGE
ANCHORED OVER THE E CONUS AND LOW PRESSURE IN THE CARIBBEAN
DESCRIBED IN THE SPECIAL FEATURES.

CARIBBEAN SEA...
SEE SPECIAL FEATURES ABOVE FOR THE 1004 MB LOW IN THE CENTRAL
CARIBBEAN. A SHORTWAVE UPPER TROUGH EXTENDS FROM S FLORIDA
ACROSS CUBA OVER THE NW CARIBBEAN GENERATING SCATTERED
SHOWERS/ISOLATED THUNDERSTORMS IN THE GULF OF HONDURAS S OF 18N
W OF 83W. ABUNDANT MOISTURE REMAINS OVER THE CARIBBEAN ENHANCING
SCATTERED/NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS S OF 16N
TO INLAND OVER NW VENEZUELA/NE COLOMBIA BETWEEN 69W-75W AND AND
WITHIN 90 NM ALONG THE COAST OF VENEZUELA BETWEEN 67W-69W.
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE ACROSS THE CENTRAL
CARIBBEAN BETWEEN 65W-84W. THE SPECIAL FEATURES LOW WILL DRIFT W
THROUGH TODAY THEN DEEPEN...POSSIBLY INTO A TROPICAL CYCLONE...
AS IT SHIFTS N TO NE TO NEAR JAMAICA BY WED AND INTO E CUBA THU
AND N OF THE AREA FRI.

ATLANTIC OCEAN...
BROAD UPPER TROUGH COVERS THE W ATLC W OF 62W SUPPORTING A COLD
FRONT THAT ENTERS THE DISCUSSION AREA E OF BERMUDA NEAR 32N62W
ALONG 27N67W TO 25N73W WHERE IT PULLS UP STATIONARY ACROSS THE
CENTRAL BAHAMAS TO 24N78W WHERE IT DISSIPATES TO OVER W CUBA
NEAR 22N81W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE S OF
THE FRONT TO OVER CUBA AND HISPANIOLA W OF 70W AND WITHIN 75/90
NM NW OF THE FRONT W OF 70W. AN UPPER RIDGE EXTENDS FROM NEAR
PUERTO RICO N TO 32N51W ENHANCING THE ABOVE ACTIVITY. THE
UPPER LOW ASSOCIATED WITH THE 1011 MB LOW IN THE SPECIAL
FEATURES COVERS THE AREA N OF 10N BETWEEN 44W-60W. AN UPPER
TROUGH IN THE NE ATLC DIPS S TO 21N E OF 35W SUPPORTING A COLD
FRONT THAT EXTENDS THROUGH 32N23W ALONG 30N27W TO 29N32W WHERE
IT DISSIPATES TO 29N37W. ISOLATED SHOWERS ARE POSSIBLE WITHIN 30
NM OF THE FRONT. A BROAD UPPER RIDGE COVERS THE TROPICAL ATLC E
OF 44W AND IS ANCHORED NEAR 10N32W. A WEAK LOW LEVEL SURFACE
TROUGH IS TO THE N OF THE UPPER RIDGE EXTENDING FROM 22N34W TO
19N35W. W ATLC COLD FRONT WILL SHIFT E TO ALONG 32N55W TO 27N61W
ON MON NIGHT THEN NE OUT OF THE AREA BY TUE NIGHT. SURFACE RIDGE
WILL BUILD OFF E CONUS BEHIND THE FRONT THROUGH WED. THE
PRESSURE GRADIENT WILL INCREASE BETWEEN THIS SURFACE RIDGE AND
THE LOW PRESSURE IN THE CARIBBEAN TUE INTO WED. THE LOW WILL
EMERGE N OF CUBA ON FRI.

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

$$
PAW




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