[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 241803
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST SAT NOV 24 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1715 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS W AFRICA INTO THE E TROPICAL
ATLC NEAR 11N15W TO 9N19W WHERE THE ITCZ BEGINS AND CONTINUES
ALONG 4N28W 6N41W TO SOUTH AMERICA NEAR 4N52W. CLUSTERS OF
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION ARE N OF 2N TO
INLAND OVER SW AFRICA E OF 16W TO THE PRIME MERIDIAN AND FROM
3N-11N BETWEEN 16W-37W.

...DISCUSSION...

GULF OF MEXICO...
BROAD UPPER TROUGH COVERS THE E CONUS DIPPING INTO THE N GULF N
OF 28N SUPPORTING A COLD FRONT THAT ENTERS THE GULF AT 24/1500
UTC ACROSS FLORIDA NEAR TAMPA CONTINUING ALONG 26N86W 26N95W TO
24N96W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 45
NM OF THE FRONT E OF 95W AND FROM 22N-29N W OF 95W. ZONAL
WESTERLY FLOW ALOFT DOMINATES THE REMAINDER OF THE GULF THIS
AFTERNOON. A SURFACE RIDGE IS BUILDING S IN THE WAKE OF THE
FRONT ANCHORED BY A 1030 MB HIGH OVER CENTRAL TEXAS AND A SECOND
1030 MB HIGH OVER CENTRAL MISSOURI. BROKEN TO OVERCAST COLD AIR
STRATOCUMULUS CLOUDS REMAIN ACROSS THE GULF S OF THE FRONT. THE
COLD FRONT WILL PUSH FURTHER S INTO THE S/CENTRAL GULF THROUGH
SUN THEN WEAKEN. ANOTHER WEAK COLD FRONT WILL ENTER THE NW GULF
EARLY TUE MORNING REACHING FROM MISSISSIPPI TO NE MEXICO TUE
EVENING THEN WEAKEN ON WED.

CARIBBEAN SEA...
A BROAD UPPER RIDGE DOMINATES THE CARIBBEAN ANCHORED OVER NE
VENEZUELA/TRINIDAD EXTENDING A RIDGE AXIS NE INTO THE CENTRAL
ATLC. THE MONSOON TROUGH EXTENDS FROM COLOMBIA NEAR 10N74W
CROSSING PANAMA INTO THE E PACIFIC REGION NEAR 8N78W. THE
SOUTHERLY FLOW ALOFT COUPLED WITH THE N TO NE MODERATE TRADE
WINDS ARE GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS
WITHIN 120/150 NM OF LINE FROM S OF HAITI NEAR 17N73W TO OVER
PANAMA NEAR 9N78W. BROKEN TO OVERCAST COLD AIR STRATOCUMULUS
CLOUDS WITH POSSIBLE ISOLATED SHOWERS ARE W OF THE ABOVE
ACTIVITY. STRONG HIGH PRESSURE WILL BUILD OVER THE W ATLC BY MON
INCREASING WINDS AND SEAS ACROSS THE CARIBBEAN SEA. FRESH TO
STRONG TRADE WINDS WILL THEN PREVAIL ACROSS THE CENTRAL
CARIBBEAN THROUGH WED.

ATLANTIC OCEAN...
AN UPPER TROUGH THAT COVERS THE E CONUS AND N GULF OF MEXICO
EXTENDS OVER THE FAR W ATLC N OF 29N W OF 70W SUPPORTING A COLD
FRONT THAT ENTERS THE REGION AT 24/1500 UTC NEAR 32N75W CROSSING
THE FLORIDA PENINSULA INTO THE GULF OF MEXICO BETWEEN CAPE
CANAVERAL TO TAMPA. THIS FRONT IS MOVING THROUGH RELATIVELY DRY
AIR...THUS NO ASSOCIATED SHOWERS ARE IN THE W ATLC. ANOTHER
BROAD UPPER TROUGH EXTENDS OVER THE W INTO THE CENTRAL ATLC N OF
26N BETWEEN 50W-65W SUPPORTING DISSIPATING COLD FRONT THAT
EXTENDS FROM A TRIPLE POINT THROUGH 32N53W ALONG 25N56W TO NE OF
THE VIRGIN ISLANDS NEAR 19N62W. A RE-ENFORCING COLD FRONT
EXTENDS FROM A 990 MB LOW WELL N OF THE DISCUSSION AREA THROUGH
32N56W ALONG 24N62W TO THE COAST OF CUBA NEAR 21N75W. THE AREA W
OF THE DISSIPATING COLD FRONT IS UNDER STRONG SUBSIDENCE AND DRY
STABLE AIR...THUS NO SHOWERS ARE ASSOCIATED WITH THIS FRONT. THE
UPPER RIDGE ANCHORED OVER NE VENEZUELA EXTENDS A RIDGE AXIS NE
ALONG 22N49W TO BEYOND 32N43W PROVIDING DIFFLUENCE ALOFT TO
GENERATE SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS
WITHIN 90 NM OF LINE FROM 25N52W TO BEYOND 32N47W. A THIRD BROAD
UPPER TROUGH COVERS THE E ATLC N OF 27W E OF 30W SUPPORTING A
COLD FRONT THAT EXTENDS THROUGH A 1012 MB LOW NEAR 31N24W ALONG
29N31W THEN NW OUT OF THE REGION NEAR 32N41W. SCATTERED SHOWERS
ARE N OF 29N BETWEEN 16W-22W. A NARROW UPPER TROUGH EXTENDS FROM
THE BROAD UPPER TROUGH NEAR 25N22W ALONG 16N34W TO NEAR 7N41W
ENHANCING THE ACTIVITY ASSOCIATED WITH THE ITCZ/MONSOON TROUGH.
A WEAK SURFACE RIDGE IS S OF THE ABOVE FRONT WITH A 1020 MB HIGH
NEAR 26N37W. THE W/CENTRAL ATLC COLD FRONTS WILL DISSIPATE
THROUGH SUN. THE FAR W ATLC COLD FRONT WILL REACH FROM BERMUDA
TO S FLORIDA SUN MORNING THEN STALL AND DISSIPATE FROM 32N56W TO
THE STRAITS OF FLORIDA MON. HIGH PRESSURE WILL THEN BUILD ACROSS
THE AREA MON THROUGH WED.

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

$$
PAW





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