[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 170551
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT WED OCT 17 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0445 UTC.

...SPECIAL FEATURES...

HURRICANE RAFAEL IS CENTERED NEAR 32.4N 62.5W AT 17/0300 UTC OR
ABOUT 117 NM E OF BERMUDA MOVING N-NE AT 25 KT. ESTIMATED
MINIMUM CENTRAL PRESSURE IS 970 MB. MAXIMUM SUSTAINED WIND SPEED
IS 75 KT WITH GUSTS TO 90 KT. SEE LATEST NHC INTERMEDIATE PUBLIC
ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT2/WTNT32 KNHC AND THE
FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22
KNHC. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 60
NM OF LINE FROM 33N60W TO 35N63W. CLUSTERS OF SCATTERED
MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 90/120 NM OF LINE
FROM NE OF THE CARIBBEAN NEAR 19N64W ALONG 26N60W TO 32N57W.

...TROPICAL WAVES...

TROPICAL WAVE IS ANALYZED FROM 15N41W ALONG 10N44W TO 6N44W
MOVING W NEAR 25 KT. SCATTERED MODERATE CONVECTION IS WITHIN 60
NM OF THE WAVE BETWEEN 9N-13N.

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

THE MONSOON TROUGH IS ANALYZED ACROSS W AFRICA INTO THE E
TROPICAL ATLC NEAR 12N16W ALONG 10N19W TO 9N25W WHERE THE ITCZ
AXIS CONTINUES ALONG 10N27W 12N33W TO 11N41W THEN RESUMES NEAR
10N46W ALONG 9N50W TO 11N54W THEN RESUMES NEAR 10N58W TO THE
COAST OF SOUTH AMERICA NEAR 9N62W. A WEAK SURFACE TROUGH IS OVER
THE W TROPICAL ATLC EXTENDING ALONG 56W BETWEEN 8N-15N WITH
ISOLATED SHOWERS WITHIN 60 NM EITHER SIDE OF THE TROUGH AXIS.
SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 60 NM OF LINE
FROM 8N18W TO 11N24W. CLUSTERS OF SCATTERED MODERATE/ISOLATED
STRONG CONVECTION ARE FROM 4N-8N BETWEEN 10W-16W...FROM 7N-12N
BETWEEN 17W-29W...AND FROM 10N-17N BETWEEN 30W-38W.

...DISCUSSION...

GULF OF MEXICO...
A BROAD UPPER TROUGH EXTENDS FROM OVER THE FAR NE CONUS/CANADIAN
MARITIMES INTO THE W ATLC SUPPORTING A DISSIPATING STATIONARY
FRONT THAT ENTERS THE GULF ACROSS THE FLORIDA PENINSULA AT
17/0300 UTC NEAR NAPLES FLORIDA ALONG 26N86W TO 28N91W WHERE IT
BECOMES A DISSIPATING WARM FRONT TO OVER SW LOUISIANA NEAR LAKE
CHARLES. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS
ARE INLAND OVER S FLORIDA S OF THE FRONT. A STRONG SHORTWAVE
UPPER TROUGH EXTENDS FROM LAKE MICHIGAN ALONG THE CENTRAL
MISSISSIPPI VALLEY TO SE TEXAS ENHANCING SCATTERED SHOWERS AND
POSSIBLE ISOLATED THUNDERSTORMS N OF 27N W OF 87W. A BROAD UPPER
RIDGE DOMINATES THE GULF WATERS WITH THE AXIS EXTENDING FROM AN
UPPER HIGH NEAR MEXICO CITY ALONG 20N ACROSS THE YUCATAN
PENINSULA INTO THE FAR NW CARIBBEAN. SCATTERED SHOWERS AND
POSSIBLE ISOLATED THUNDERSTORMS ARE S OF 25N BETWEEN 83W-87W TO
INLAND OVER W CUBA AND THROUGH THE YUCATAN CHANNEL. A WEAK
SURFACE RIDGE IS ANCHORED BY A 1014 MB HIGH OVER NW SOUTH
CAROLINA. A WEAK FRONT WILL DISSIPATE OVERNIGHT. A SECOND COLD
FRONT WILL MOVE OFF THE TEXAS COAST EARLY THU AND REACH FROM
NEAR CEDAR KEY FLORIDA TO BROWNSVILLE TEXAS FRI MORNING THEN
DISSIPATE FROM NEAR FORT MYERS FLORIDA TO CORPUS CHRISTI TEXAS
SAT. WEAK SURFACE RIDGE WILL BUILD ACROSS THE AREA OVER THE
WEEKEND.

CARIBBEAN SEA...
A BROAD UPPER RIDGE EXTENDS AN AXIS ALONG 20N FROM ACROSS MEXICO
AND THE YUCATAN PENINSULA TO OVER THE FAR NW CARIBBEAN TO 83W. A
NARROW UPPER TROUGH EXTENDS FROM THE W ATLC INTO THE NW
CARIBBEAN ACROSS CUBA NEAR 22N78W TO THE TIP OF HONDURAS/
NICARAGUA. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS
ARE N OF 21N BETWEEN 81W-86W TO INLAND OVER W CUBA AND THROUGH
THE YUCATAN CHANNEL AND IN THE GULF OF HONDURAS S OF 18N BETWEEN
83W-87W. A SECOND BROAD UPPER RIDGE COVERS THE REMAINDER OF THE
CARIBBEAN ANCHORED NEAR 15N68W. SCATTERED SHOWERS/ISOLATED
THUNDERSTORMS ARE N OF 14N E OF 67W TO ACROSS THE LESSER
ANTILLES AND S OF 14N BETWEEN 65W-72W. THE MONSOON TROUGH
EXTENDS ACROSS THE SW CARIBBEAN FROM COLOMBIA NEAR 9N75W TO
ACROSS W PANAMA/COSTA RICA INTO THE THE E PACIFIC REGION NEAR
9N83W GENERATING CLUSTERS OF SCATTERED SHOWERS/ISOLATED
THUNDERSTORMS S OF 11N BETWEEN 75W-80W AND WITHIN 75 NM ALONG
THE REMAINDER OF THE COAST OF COLOMBIA. ISOLATED SHOWERS AND
POSSIBLE ISOLATED THUNDERSTORMS DOT THE AREA S OF 17N BETWEEN
73W-83W. HURRICANE RAFAEL WILL CONTINUE TO PULL FURTHER N-NE.
RESULTANT SWELLS OVER THE NE CARIBBEAN SEA PASSAGES WILL
DIMINISH OVERNIGHT. THE W ATLC SURFACE TROUGH WILL MOVE INTO THE
E CARIBBEAN TUE EVENING REACHING 76W BY SUN.

ATLANTIC OCEAN...
THE PRIMARY CONCERN AGAIN THIS MORNING IS HURRICANE RAFAEL E OF
BERMUDA...SEE SPECIAL FEATURES ABOVE. AN UPPER TROUGH EXTENDS
FROM OVER THE FAR NE CONUS/CANADIAN MARITIMES INTO THE W ATLC
THROUGH 32N75W NARROWING AS IT ENTERS THE NW CARIBBEAN ACROSS
CUBA NEAR 22N78W SUPPORTING A COLD FRONT THAT ENTERS THE REGION
AT 17/0300 UTC THROUGH 32N69W TO 30N73W WHERE IT DISSIPATES
ALONG 28N76W THEN TO OVER FLORIDA NEAR FORT LAUDERDALE WHERE IT
BECOMES A DISSIPATING STATIONARY FRONT AS IT CONTINUES INTO THE
GULF OF MEXICO. ISOLATED SHOWERS ARE POSSIBLE WITHIN 60-75 NM
OF THE FRONT N OF 30N. A BROAD UPPER RIDGE EXTENDS FROM THE E
CARIBBEAN OVER THE VIRGIN ISLANDS NEAR 18N64W ALONG 27N55W TO
BEYOND 32N53W AND E OF THE HURRICANE RAFAEL. AN UPPER TROUGH
EXTENDS FROM THE E ATLC NEAR 32N23W ALONG 27N33W TO AN UPPER LOW
NEAR 21N41W INTO THE TROPICS TO THE BASE NEAR 5N51W. THIS UPPER
TROUGH IS ENHANCING THE ACTIVITY ASSOCIATED WITH THE MONSOON
TROUGH. THE CENTRAL AND E ATLC IS DOMINATED BY A SURFACE RIDGE
ANCHORED WELL N OF THE DISCUSSION AREA. THE WEAKENING COLD FRONT
WILL DISSIPATE WED. ANOTHER COLD FRONT WILL MOVE INTO THE NW
WATERS FRI AND EXTEND FROM 32N73W TO WEST PALM BEACH BY SAT AND
FROM 32N70W TO WEST PALM BEACH BY SUN.

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

$$
PAW





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