[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 112357
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT TUE AUG 11 2015

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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2315 UTC.

...TROPICAL WAVES...

TROPICAL WAVE IN THE E TROPICAL ATLC EXTENDS ALONG 24W/25W FROM
11N-20N MOVING W 5-10 KT OVER THE PAST 24 HOURS. THE GLOBAL
MODEL SHOWS THE WAVE ALONG THE 700 MB TROUGH AND THE TOTAL
PRECIPITABLE WATER IMAGERY SHOWS THE WAVE ALONG THE LEADING EDGE
OF A SURGE OF DEEP MOISTURE. NO ASSOCIATED DEEP CONVECTION.

TROPICAL WAVE IN THE CENTRAL TROPICAL ATLC EXTENDS ALONG 45W
FROM 9N-17N MOVING W-SW 10-15 KT OVER THE PAST 24 HOURS. THE
GLOBAL MODEL SHOWS THE WAVE ALONG A WEAK 700 MB TROUGH AND THE
TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE IS EMBEDDED
WITHIN A WEAK SURGE OF MODERATE MOISTURE. THE NOAA/NESDIS
AEROSOL PRODUCT AND THE LAST VISIBLE SATELLITE IMAGERY INDICATES
THAT THE WAVE IS ALONG THE LEADING EDGE OF A PLUMB OF AEROSOLS
OR SAHARAN DUST. NO ASSOCIATED DEEP CONVECTION.

TROPICAL WAVE IN THE E CARIBBEAN EXTENDS ALONG 65W/66W FROM 12N-
19N MOVING W 15-20 KT OVER THE PAST 24 HOURS. THE GLOBAL MODEL
SHOWS THE WAVE TRAILING A 700 MB TROUGH AND THE TOTAL
PRECIPITABLE WATER IMAGERY SHOWS THE WAVE ALONG THE LEADING EDGE
OF A SURGE OF DEEP MOISTURE. NO ASSOCIATED DEEP CONVECTION.
ISOLATED SHOWERS ARE FROM 13N-19N BETWEEN 64W-70W.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL
ATLC NEAR 15N17W ALONG 9N27W TO 9N37W WHERE THE ITCZ BEGINS AND
CONTINUES TO E OF THE CENTRAL TROPICAL WAVE NEAR 10N43W THEN
RESUMES W OF THE WAVE NEAR 9N46W AND CONTINUES ALONG 7N52W TO
SOUTH AMERICA NEAR 8N60W. CLUSTERS OF SCATTERED MODERATE/
ISOLATED STRONG CONVECTION ARE WITHIN 90 NM OF LINE FROM 5N16W
7N21W TO 8N36W.

...DISCUSSION...

GULF OF MEXICO...
A BROAD UPPER RIDGE REMAINS OVER THE N GULF OF MEXICO AND SE
CONUS ANCHORED OVER NE TEXAS/SE OKLAHOMA. AN UPPER TROUGH IS
OVER NEW ENGLAND TO THE MID ATLANTIC STATES SUPPORTING A COLD
FRONT THAT REMAINS INLAND. BANDS OF SCATTERED TO NUMEROUS
SHOWERS ARE MOVING S ACROSS THE SE CONUS AND INTO THE GULF
WATERS N OF 29N W OF 90W TO INLAND OVER LOUISIANA AND E TEXAS. A
REMNANT SURFACE TROUGH EXTENDS FROM 28N89W ALONG 27N92W TO
24N94W. AN UPPER LOW IS OVER THE YUCATAN PENINSULA AND COUPLED
WITH THE DIURNAL SURFACE TROUGH INLAND OVER THE YUCATAN
PENINSULA ARE GENERATING SCATTERED SHOWERS/THUNDERSTORMS S OF
22N BETWEEN 88W-92W. ISOLATED SHOWERS AND POSSIBLE ISOLATED
THUNDERSTORMS DOT THE W/CENTRAL GULF FROM 22N-27N W OF 90W.
AFTERNOON THUNDERSTORMS THAT DEVELOPED OVER W CUBA ARE MOVING NW
INTO THE GULF WATERS FROM 22N-24N BETWEEN 82W-86W IN THE YUCATAN
CHANNEL. A WEAK SURFACE RIDGE EXTENDS FROM THE W ATLC ACROSS S
FLORIDA TO THE NE TEXAS COAST. THE WEAK RIDGE WILL PERSIST
THROUGH FRI. A WEAK COLD FRONT WILL MOVE S ACROSS THE NE AND
N/CENTRAL GULF WED THEN STALL FROM THE FLORIDA PANHANDLE TO THE
CENTRAL GULF ON THU WITH WEAK LOW DEVELOPING ALONG THE FRONT ON
FRI.

CARIBBEAN SEA...
THE UPPER TROUGH OVER THE YUCATAN PENINSULA COVERS THE FAR NW
CARIBBEAN. A SECOND UPPER LOW IS CENTERED S OF THE WINDWARD
PASSAGE INDUCING AN UPPER RIDGE THAT EXTENDS FROM PANAMA TO W
CUBA. THIS UPPER RIDGE IS PROVIDING DIFFLUENCE ALOFT TO GENERATE
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS SW OF LINE FROM 20N84W
ALONG 16N81W TO PANAMA NEAR 7N78W. THE UPPER LOW COUPLED WITH
DAYTIME HEATING IS GENERATING SCATTERED SHOWERS/ISOLATED
THUNDERSTORMS INLAND OVER HISPANIOLA...CUBA...AND JAMAICA. AN
UPPER RIDGE ANCHORED IN THE W TROPICAL ATLC IS PROVIDING
DIFFLUENCE ALOFT TO GENERATE SCATTERED SHOWERS/ISOLATED
THUNDERSTORMS FROM 13N-16N BETWEEN 60W-64W INCLUDING SOME OF THE
ISLANDS OF THE LESSER ANTILLES. LIGHT TO MODERATE TRADE WINDS
WILL PREVAIL ACROSS THE BASIN THROUGH FRI EXCEPT FRESH TO
LOCALLY STRONG TRADE WINDS ALONG THE COASTS OF COLOMBIA AND NW
VENEZUELA. E CARIBBEAN TROPICAL WAVE WILL MOVE ACROSS THE
CENTRAL CARIBBEAN WED AND WED NIGHT THEN THE W CARIBBEAN THU
THROUGH FRI. A SECOND TROPICAL WAVE WILL ENTER THE E CARIBBEAN
FRI.

...HISPANIOLA...
CURRENTLY THE UPPER LOW COUPLED WITH THE DAYTIME HEATING ARE
GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ACROSS
PORTIONS OF THE ISLAND. THE UPPER LOW WILL DRIFT W LEAVING AN
UPPER TROUGH OVER THE ISLAND THROUGH THU NIGHT BEFORE SOUTHERLY
FLOW ALOFT MOVES IN ON FRI. THE E CARIBBEAN TROPICAL WAVE WILL
MOVE ACROSS THE ISLAND LATE TONIGHT/EARLY WED THROUGH EARLY FRI.
THIS WILL BRING AN INCREASE IN MOISTURE AND SHOWERS/
THUNDERSTORMS THROUGH FRI.

ATLANTIC OCEAN...
THE UPPER RIDGE OVER THE GULF OF MEXICO AND THE SE CONUS EXTENDS
INTO THE W ATLC FROM NE FLORIDA TO BEYOND 32N75W. A WEAK UPPER
TROUGH COVERS THE REMAINDER OF THE W ATLC W OF 65W AND IS
GENERATING ISOLATED SHOWERS/THUNDERSTORMS WITHIN 120 NM OF LINE
FROM 25N79W TO 30N67W. AN UPPER LOW IN THE E ATLC IS CENTERED
NEAR 30N23W AND IS SUPPORTING A SURFACE TROUGH THAT EXTENDS FROM
31N27W TO 25N24W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE N
OF 26N BETWEEN 19W-23W. THE REMAINDER OF THE ATLC IS DOMINATED
BY A SURFACE RIDGE ANCHORED BY A 1029 MB HIGH W OF THE AZORES
AND EXTENDING A SURFACE RIDGE ALONG 32N56W ACROSS S FLORIDA AND
INTO THE GULF OF MEXICO. THE ATLC SURFACE RIDGE WILL DRIFT S
INTO STRAITS OF FLORIDA WED THEN REORGANIZE AND GRADUALLY SHIFT
N ALONG 28N BY FRI. A WEAK COLD FRONT WILL MOVE OFFSHORE OF NE
FLORIDA WED NIGHT THEN IMMEDIATELY STALL AND MEANDER ACROSS THE
FAR NW WATERS THROUGH FRI.

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

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