[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 261039
TWDAT

TROPICAL WEATHER DISCUSSION...
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT TUE AUG 26 2008

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1015 UTC.

...SPECIAL FEATURES...
TROPICAL STORM GUSTAV WAS UPGRADED TO HURRICANE AT 26/0900 UTC
BASED ON OBSERVATIONS FROM AIR FORCE RESERVE RECONNAISSANCE
AIRCRAFT. GUSTAV IS CENTERED NEAR 17.2N 71.9W AT 26/0900 UTC OR
ABOUT 87 NM SOUTH-SOUTHEAST OF PORT AU PRINCE HAITI AND ABOUT
260 NM SOUTHEAST OF GUANTANAMO CUBA MOVING NORTHWEST AT 8 KT.
LATEST MINIMUM CENTRAL PRESSURE AS REPORTED FROM AN AIR FORCE
RESERVE RECONNAISSANCE AIRCRAFT IS 984 MB. MAXIMUM SUSTAINED
WIND SPEED HAS INCREASED TO 75 KT WITH GUSTS TO 90 KT MAKING
GUSTAV IS A CATEGORY ONE HURRICANE ON THE SAFFIR-SIMPSON SCALE.
PLEASE SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO
HEADERS MIATCMAT2/WTNT22 KNHC AND/OR THE PUBLIC ADVISORY
MIATCPAT2/WTNT32 KNHC FOR MORE DETAILS. SCATTERED MODERATE/
STRONG CONVECTION COVERS THE AREA FROM 15N-18N BETWEEN 70W-74W
WITH CLUSTERS OF SCATTERED SHOWERS/THUNDERSTORMS DOTTING THE
AREA FROM THE COAST OF VENEZUELA AND COLOMBIA TO OVER HISPANIOLA
BETWEEN 67W-74W.

...TROPICAL WAVES...
A 1008 MB LOW IS OVER THE CAPE VERDE ISLANDS NEAR 15.5N24W
MOVING WSW NEAR 10 KT. THIS LOW IS EMBEDDED WITHIN A BROAD AREA
OF DEEP LAYERED MOISTURE WITH ANY DEEP CONVECTION WELL REMOVED
FROM THE LOW.

A 1009 MB LOW IS CENTERED NEAR 12N34W HAS REMAINED NEAR
STATIONARY FOR THE PAST 24 HOURS. ISOLATED SHOWERS ARE WITHIN
90/120 NM OF THE LOW.

TROPICAL WAVE IS ALONG 38W S OF 16N MOVING W NEAR 10 KT. TYPICAL
INVERTED-V CURVATURE IS OBSERVED IN THE LOW LEVEL CLOUDS ON
SATELLITE IMAGERY. ANY DEEP CONVECTION IS EMBEDDED WITHIN THE
ITCZ.

TROPICAL WAVE IS IN THE E/CENTRAL CARIBBEAN IS ALONG 71W S OF
12N MOVING W NEAR 20 KT. WAVE REMAINS EMBEDDED WITHIN THE DEEP
LAYERED MOISTURE BUT IS MOSTLY INLAND OVER SOUTH AMERICA...THUS
NO ASSOCIATED SHOWERS OVER THE CARIBBEAN WATERS.

TROPICAL WAVE IN THE W CARIBBEAN IS ALONG 86W/87W S OF 20N
MOVING W NEAR 20 KT. THIS WAVE IS EMBEDDED WITHIN SOME DRIER
AIR...THUS ONLY ISOLATED SHOWERS/THUNDERSTORMS ARE IN THE GULF
OF HONDURAS S OF 19N W OF 85W TO INLAND OVER CENTRAL ALMERIA AND
THE YUCATAN PENINSULA.

...THE ITCZ...
THE ITCZ AXIS IS ANALYZED ALONG 16N15W 13N25W 9N34W 7N52W 9N62W.
SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 75 NM OF LINE
FROM 12N24W ACROSS THE ITCZ TO 14N29W WITH CLUSTERS OF SIMILAR
CONVECTION FROM 5N-9N BETWEEN 32W-47W. CLUSTERS OF SCATTERED
MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 120/150 NM OF THE
ITCZ FROM 27W-32W.

...DISCUSSION...

GULF OF MEXICO...
T.D. FAY REMAINS INLAND OVER CENTRAL MISSISSIPPI/ALABAMA MOVING
NE WITH A SURFACE TROUGH TRAILING INTO THE GULF WATERS NEAR
MOBILE ALABAMA SW TO 28N92W GENERATING SCATTERED SHOWERS/
ISOLATED THUNDERSTORMS N OF 28N BETWEEN 86W-95W. SMALL UPPER LOW
IS CENTERED OFF THE TEXAS COAST NEAR 28N94W COVERING THE NW GULF
AND AN UPPER RIDGE EXTENDING E ACROSS MEXICO ALONG 21N OVER THE
SW GULF PROVIDING UPPER LEVEL DIFFLUENCE TO GENERATE SCATTERED
SHOWERS/ISOLATED THUNDERSTORMS ALONG THE COAST OF MEXICO FROM
TUXPAN TO LAGUNA MADRE W OF 96W. AN UPPER HIGH REMAINS ANCHORED
IN THE FLORIDA STRAITS NEAR 24N812W COVERING THE E GULF. THIS
SCENARIO IS KEEPING THE REMAINDER OF THE GULF TRANQUIL AGAIN
THIS MORNING.

CARIBBEAN SEA...
THE MAIN CONCERN TODAY FOR THE CARIBBEAN IS HURRICANE GUSTAV IN
THE N/CENTRAL CARIBBEAN...SEE SPECIAL FEATURES ABOVE. UPPER
OUTFLOW IS BECOMING A LITTLE MORE ORGANIZED WITH MAINLY EASTERLY
UPPER FLOW OVER THE CARIBBEAN E OF 75W. AN UPPER RIDGE IS
ANCHORED IN THE FLORIDA STRAITS GIVING THE W CARIBBEAN E TO SE
UPPER FLOW. THE ITCZ AXIS CROSSES THE EXTREME S CARIBBEAN
GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 12N W
OF 74W TO INLAND OVER COLOMBIA THROUGH COSTA RICA. DEEP LAYERED
MOISTURE DOMINATES THE ENTIRE CARIBBEAN. HOWEVER...OTHER THAN
THE ACTIVITY NOTED ABOVE AND THAT ASSOCIATED WITH THE TROPICAL
WAVE ALONG 86W/87W...THE SKIES REMAIN RATHER CLEAR THIS MORNING
OVER THE REMAINDER OF THE AREA.

ATLANTIC OCEAN...
AN UPPER RIDGE COVERS THE FAR W ATLC W OF 73W ANCHORED IN THE
FLORIDA STRAITS NEAR 24N81W. BROAD UPPER TROUGH IS OVER THE
REMAINDER OF THE W ATLC COVERING THE AREA FROM 60W-72W. A
SURFACE TROUGH IS JUST TO THE E OF THE UPPER TROUGH EXTENDING
ALONG 31N59W TO 22N65W GENERATING SCATTERED/NUMEROUS SHOWERS AND
SCATTERED THUNDERSTORMS WITHIN 175 NM W OF THE SURFACE TROUGH
BETWEEN 24N-28N. CLUSTERS OF SCATTERED SHOWERS/ISOLATED
THUNDERSTORMS ARE FROM 21N-30N BETWEEN 60W-67W. SCATTERED
SHOWERS WITH POSSIBLE ISOLATED THUNDERSTORMS ARE FROM 18N-22N
BETWEEN 63W-71W INCLUDING PUERTO RICO AND THE VIRGIN ISLANDS. AN
UPPER RIDGE IS ANCHORED IN THE S/CENTRAL ATLC NEAR 19N61W. A
WEAK 1011 MB SURFACE LOW IS BENEATH THIS UPPER RIDGE NEAR 19N54W
WITH THE UPPER LEVEL DIFFLUENCE ENHANCING SCATTERED MODERATE/
ISOLATED STRONG CONVECTION FROM 19N-22N BETWEEN 53W-56W. A
SECOND BUT BENIGN UPPER TROUGH COVERS THE E/CENTRAL ATLC
EXTENDING THROUGH 32N32W ALONG 23N35W INTO THE TROPICS TO 12N44W
AND A SECOND UPPER RIDGE COVERS THE REMAINDER OF THE E ATLC
ANCHORED JUST S OF THE CANARY ISLANDS. BROAD SURFACE RIDGE
REMAINS OVER THE ATLC N OF 25N E OF 75W ANCHORED BY A SERIES OF
HIGHS N OF THE REGION AND A WEAKNESS NEAR THE SURFACE TROUGH.

$$
WALLACE





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