[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 140543
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT FRI SEP 14 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
0515 UTC.

...SPECIAL FEATURES...
TROPICAL STORM NADINE IS CENTERED NEAR 25.0N 53.7W 14/0300 UTC
OR ABOUT 655 NM NE OF THE NORTHERN LEEWARD ISLANDS AND ABOUT 730
NM SE OF BERMUDA MOVING NNW AT 13 KT. ESTIMATED MINIMUM CENTRAL
PRESSURE IS 989 MB. MAXIMUM SUSTAINED WIND SPEED IS 60 KT WITH
GUSTS TO 75 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO
HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. SCATTERED/
NUMEROUS STRONG CONVECTION IS WITHIN 120 NM OF THE CENTER OVER
THE NW QUADRANT. SCATTERED MODERATE TO STRONG CONVECTION IS FROM
24N-29N BETWEEN 51W-56W...WITHIN 75 NM OF LINE FROM 24N47W TO
27N51W...AND WITHIN 45/60 NM OF LINE FROM 21N77W TO 24N49W.

...TROPICAL WAVES...

TROPICAL WAVE IS SE OF TROPICAL STORM NADINE EXTENDING FROM
14N44W THROUGH A 1013 MB LOW NEAR 9N41W TO 7N40W MOVING W 15-20
KT. WAVE IS EMBEDDED WITHIN AN AREA OF DEEP MOISTURE AS DEPICTED
ON THE TOTAL PRECIPITABLE WATER IMAGERY. CLUSTERS OF SCATTERED
MODERATE/ISOLATED STRONG CONVECTION ARE FROM 9N-16N BETWEEN
41W-48W.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS AFRICA ENTERING THE E TROPICAL
ATLC NEAR 11N15W CONTINUING ALONG 8N20W TO 9N30W WHERE THE ITCZ
BEGINS CONTINUING TO E OF THE TROPICAL WAVE NEAR 10N38W THEN
RESUMES W OF THE TROPICAL WAVE NEAR 7N45W TO SOUTH AMERICA NEAR
5N54W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION
ARE WITHIN 200 NM S OF THE MONSOON TROUGH E OF 16W TO INLAND
OVER W AFRICA AND WITHIN 180/200 NM S OF THE MONSOON TROUGH/ITCZ
BETWEEN 26W-34W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE
WITHIN 120 NM N OF THE ITCZ BETWEEN 46W-50W.

...DISCUSSION...

GULF OF MEXICO...
AN UPPER LOW IS CENTERED OVER TENNESSEE EXTENDING AN UPPER
TROUGH S OVER THE CENTRAL GULF OF MEXICO. AN UPPER RIDGE EXTENDS
ACROSS MEXICO TO OVER THE W GULF WHILE UPPER RIDGE OVER THE W
ATLC EXTENDS OVER THE E GULF. THIS IS GIVING MOST OF THE GULF
UNSETTLED WEATHER TONIGHT. CLUSTERS OF SCATTERED SHOWERS/ISOLATED
THUNDERSTORMS ARE OVER THE E GULF FROM 25N-29N E OF 88W TO THE
COAST OF FLORIDA. SIMILAR ACTIVITY IS OVER THE W GULF FROM
22N-29N W OF 93W. A REMNANT SURFACE TROUGH IS IN THE STRAITS OF
FLORIDA FROM THE W ATLC NEAR 24N80W ALONG 24N82W TO 23N87W
GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 25N E
OF 87W TO OVER THE FLORIDA KEYS AND THROUGH THE STRAITS OF
FLORIDA. SURFACE RIDGE REMAINS OVER THE GULF ANCHORED BY A 1026
MB HIGH OVER VIRGINIA. THE SURFACE TROUGH WILL REMAIN NEARLY
STATIONARY TONIGHT THEN DISSIPATING ON FRI. OTHERWISE BROAD HIGH
PRESSURE WILL REMAIN THROUGH EARLY NEXT WEEK.

CARIBBEAN SEA...
A BROAD UPPER RIDGE OVER THE W ATLC DOMINATES THE N CARIBBEAN
WHILE A SECOND UPPER RIDGE DOMINATES THE SW WATERS. A SURFACE
TROUGH THAT EXTENDS THROUGH THE STRAITS OF FLORIDA IS GENERATING
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 21N ACROSS W CUBA
AND THROUGH THE YUCATAN CHANNEL BETWEEN 81W-87W...AND OVER HAITI
AND WITHIN 30 NM ALONG THE IMMEDIATE COASTS. THE MONSOON TROUGH
EXTENDS FROM COLOMBIA ALONG 10N ACROSS COSTA RICA INTO THE E
PACIFIC REGION GENERATING ISOLATED SHOWERS/THUNDERSTORMS S OF
12N BETWEEN 73W-83W AND FROM 12N-15N W OF 82W TO INLAND OVER
NICARAGUA. A CUTOFF UPPER LOW IS CENTERED JUST N OF THE VIRGIN
ISLANDS/PUERTO RICO EXTENDING AN UPPER TROUGH OVER THE E
CARIBBEAN TO THE ABC ISLANDS COVERING THE CARIBBEAN E OF 71W.
LIGHT TO MODERATE TRADE WINDS ARE ACROSS THE BASIN WITH LOCALLY
FRESH TRADES IN THE S CENTRAL CARIBBEAN. OTHERWISE THE REMAINDER
OF THE CARIBBEAN IS UNDER FAIR WEATHER TONIGHT. BROAD HIGH
PRESSURE OVER THE W ATLC WILL MAINTAIN TRADE WINDS THROUGH THE
WEEKEND.

ATLANTIC OCEAN...
THE PRIMARY CONCERN TONIGHT REMAINS TROPICAL STORM NADINE IN THE
CENTRAL ATLC. SEE SPECIAL FEATURES ABOVE. AN UPPER RIDGE
DOMINATES THE W ATLC ANCHORED OVER THE CENTRAL BAHAMA ISLANDS. A
SURFACE RIDGE REMAINS OVER THE W ATLC INTO THE GULF OF MEXICO
ANCHORED BY A 1027 MB HIGH OVER TENNESSEE. A REMNANT SURFACE
TROUGH REMAINS OVER THE W ATLC EXTENDING FROM A STATIONARY
BOUNDARY N OF THE DISCUSSION AREA THROUGH 32N61W ALONG 29N68W
THROUGH THE BAHAMA ISLANDS NEAR 23N76W INTO THE GULF OF MEXICO
THROUGH THE STRAITS OF FLORIDA NEAR 24N80W. SCATTERED SHOWERS/
ISOLATED THUNDERSTORMS ARE WITHIN 60/75 NM EITHER SIDE OF THE
FRONT/SURFACE TROUGH N OF 28N AND S OF 25N W OF 78W TO OVER THE
FLORIDA KEYS AND CUBA. A CUTOFF UPPER LOW IS CENTERED JUST N OF
THE VIRGIN ISLANDS/PUERTO RICO EXTENDING AN UPPER TROUGH OVER
THE E CARIBBEAN AND NNE TO NEAR 27N62W. BROAD UPPER LOW REMAINS
OVER THE NE ATLC COVERING THE AREA N OF 24N BETWEEN 15W-35W
GENERATING CLUSTERS OF ISOLATED SHOWERS AND POSSIBLE ISOLATED
THUNDERSTORMS N OF 28N BETWEEN 28W-37W. THE SURFACE TROUGH WILL
LINGER OVER THE SAME GENERAL AREA INTO THE WEEKEND BECOMING
DIFFUSE BY SUN. HIGH PRESSURE WILL BUILD IN ITS WAKE THROUGH
EARLY NEXT WEEK. TROPICAL STORM NADINE WILL MOVE N THROUGH SAT
THEN TURN TOWARD THE NE OUT OF THE DISCUSSION AREA FIRST OF NEXT
WEEK.

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

$$
PAW





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