[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 100002
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT THU AUG 09 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 2315 UTC.

...SPECIAL FEATURE...

TROPICAL STORM ERNESTO IS CENTERED NEAR 18.2N 95.8W...AS OF 0000
UTC...OR ABOUT 80 NM W OF COATZACOALCOS MEXICO...AND 65 NM SSE
OF VERACRUZ MEXICO. ERNESTO IS MOVING W AT 10 KT. MINIMUM
CENTRAL PRESSURE IS 996 MB WITH MAXIMUM SUSTAINED WINDS OF 40 KT
WITH GUSTS TO 50 KT. ERNESTO MADE LANDFALL EARLIER TODAY AND
CONTINUES TO MOVE FARTHER INLAND OVER MEXICO. THE STORM IS
EXPECTED TO CONTINUE WEAKENING OVER LAND. PLEASE READ THE LATEST
NHC
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT5/WTNT25 KNHC
AND THE PUBLIC ADVISORY UNDER AWIPS/WMO MIATCPAT5/WTNT35 KNHC
FOR MORE DETAILS. NUMEROUS STRONG CONVECTION IS S OF MEXICO FROM
14N-16N BETWEEN 94W-99W...AND INLAND OVER MEXICO FROM 18N-22N
BETWEEN 96W-99W. NUMEROUS MODERATE/SCATTERED STRONG CONVECTION
IS ELSEWHERE FROM 16N-19N BETWEEN 91W-100W.

TROPICAL DEPRESSION SEVEN FORMED AT 2100 UTC CENTERED NEAR 13.7N
43.8W...OR ABOUT 1005 NM E OF THE WINDWARD ISLANDS...MOVING W AT
17 KT. MINIMUM CENTRAL PRESSURE IS 1010 MB. MAXIMUM SUSTAINED
WIND SPEEDS ARE 30 KT WITH GUSTS TO 40 KT. PLEASE READ THE
LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS
MIATCMAT2/WTNT22 KNHC AND THE PUBLIC ADVISORY UNDER AWIPS/WMO
MIATCPAT2/WTNT32 KNHC FOR MORE DETAILS. A CLUSTER OF STRONG
CONVECTION IS W OF THE CENTER FROM 12N-14N BETWEEN 45W-48W.
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 13N-15N
BETWEEN 42W-45W.

TROPICAL WAVE IS ABOUT TO EMERGE OFF THE COAST OF AFRICA. IT IS
CURRENTLY ALONG 16W AND IS ATTACHED TO A 1004 MB SURFACE LOW
NEAR 16N16W. THE WAVE ALREADY HAS CYCLONIC LOW-LEVEL FLOW
ASSOCIATED WITH IT...WHICH IS VERY CLEAR IN SATELLITE IMAGERY.
THE MOISTURE SURGE ASSOCIATED WITH THE WAVE CAN ALSO BE SEEN IN
TOTAL PRECIPITABLE WATER IMAGERY. A CLUSTER OF STRONG CONVECTION
IS NEAR THE LOW CENTER FROM 14N-16N BETWEEN 16W-18W.
ENVIRONMENTAL CONDITIONS ARE CONDUCIVE FOR POSSIBLE SLOW
DEVELOPMENT OF THIS SYSTEM OVER THE NEXT COUPLE OF DAYS.

...TROPICAL WAVES...

TROPICAL WAVE IS ALONG 26N63W TO 20N67W MOVING NW NEAR 20 KT.
THIS OPEN WAVE IS THE REMNANTS OF T.S. FLORENCE THAT DISSIPATED
SEVERAL DAYS AGO. SATELLITE IMAGERY INDICATES BROAD LOW-LEVEL
CYCLONIC FLOW IS AROUND THE WAVE AXIS. THE WAVE ALSO LIES IN THE
MIDDLE OF A SURGE OF DEEP LAYER MOISTURE PRESENT IN TOTAL
PRECIPITABLE WATER IMAGERY. AN UPPER LEVEL TROUGH NE OF THE WAVE
WITH THE TAIL AXIS EXTENDING OVER THE WAVE IS HELPING ENHANCE
CONVECTION. SCATTERED MODERATE CONVECTION IS FROM 20N-22N
BETWEEN 60W-63W. SIMILAR ACTIVITY IS FROM 21N-24N BETWEEN
63W-68W.

TROPICAL WAVE IS MOVING INTO THE WESTERN CARIBBEAN ALONG 79W
FROM 13N-22N MOVING W AT 15 KT. A LARGE AREA OF ENHANCED DEEP
LAYER MOISTURE IS PRESENT ACROSS THE CENTRAL AND EASTERN
CARIBBEAN ASSOCIATED WITH THE WAVE AS WELL AS AN UPPER LEVEL LOW
CENTERED S OF CUBA NEAR 19N79W. THE UPPER LEVEL LOW IS PROVIDING
A LARGE AREA OF DIFFLUENCE ALOFT ACROSS THE CENTRAL CARIBBEAN.
IT IS HARD TO DIFFERENTIATE WHAT AREAS OF CONVECTION ARE
ASSOCIATED WITH THE WAVE AND WITH THE UPPER LOW. REGARDLESS OF
THE CAUSE...SCATTERED STRONG CONVECTION IS FROM 17N-20N BETWEEN
73W-80W...AND FROM 20N-23N BETWEEN 76W-84W. THESE AREAS COVER
MUCH OF HISPANIOLA...JAMAICA...AND CUBA. HEAVY RAINFALL AND
FLOODING ALONG WITH MUDSLIDES ARE POSSIBLE ACROSS MUCH OF THE
ISLANDS.

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

THE MONSOON TROUGH EXTENDS ACROSS W AFRICA THROUGH A TROPICAL
WAVE/LOW STILL OVER AFRICA TO THE COAST OF SENEGAL AT 14N17W
WHERE IT CONTINUES OVER WATER ALONG 13N25W 14N35W. THE ITCZ
BEGINS ON THE W SIDE OF T.D. SEVEN ALONG 11N45W 9N52W 10N59W.
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 8N-10N
BETWEEN 18W-22W...AND FROM 9N-11N BETWEEN 52W-55W.

...DISCUSSION...

THE GULF OF MEXICO...
TROPICAL STORM ERNESTO CONTINUES TO BRING SOME WIND AND RAIN
OVER THE EXTREME SW GULF OF MEXICO WITH THE MAJORITY OF THE
SHOWERS/THUNDERSTORMS INLAND OVER MEXICO. SEE SPECIAL FEATURES
ABOVE FOR MORE DETAILS. MOSTLY CLEAR SKIES COVER THE REMAINDER
OF THE GULF WATERS DUE TO DRY AIR ALOFT AROUND AN UPPER LEVEL
RIDGE CENTERED N OF ERNESTO NEAR 24N97W. THE RIDGE IS SUPPORTING
WEAK SURFACE RIDGING ACROSS THE NORTHERN GULF. HOWEVER...AN
UPPER LEVEL TROUGH OVER THE EASTERN CONUS IS SUPPORTING SOME
SHOWERS/THUNDERSTORMS ALONG THE NORTHERN GULF COAST MOSTLY OVER
LOUISIANA. SOME LARGE CLUSTERS OF SHOWERS/THUNDERSTORMS ARE ALSO
OVER THE FLORIDA PENINSULA. EXPECT ERNESTO TO CONTINUE TO MOVE
INLAND OVER MEXICO. WEAK SURFACE RIDGING WILL REMAIN OVER THE
NORTHERN GULF WHILE SHOWERS/THUNDERSTORMS CONTINUE ALONG THE NE
COAST AS WELL AS OVER THE SE GULF AS MOISTURE ASSOCIATED WITH A
TROPICAL WAVE APPROACHES THE AREA.

THE CARIBBEAN SEA...
AN UPPER LEVEL LOW COVERS MUCH OF THE BASIN CENTERED S OF CUBA
NEAR 19N79W. DRY AIR ALOFT IS WRAPPING AROUND THE W SIDE OF THE
LOW KEEPING THE NW CARIBBEAN MOSTLY DRY. THE E SIDE OF THE LOW
WHERE THE STRONGEST DIFFLUENCE IS ALSO COINCIDES WITH A TROPICAL
WAVE ALONG 79W. THE COMBINATION OF THE WAVE AND THE UPPER LOW IS
SUPPORTING SHOWERS/THUNDERSTORMS ACROSS MUCH OF THE NORTHERN
CARIBBEAN INCLUDING JAMAICA...HISPANIOLA...AND CUBA. SEE
TROPICAL WAVE SECTION ABOVE FOR MORE DETAILS. HEAVY
RAINFALL...FLOODING...AND MUDSLIDES ARE POSSIBLE IN AREAS THAT
HAVE ALREADY RECEIVED LARGE AMOUNTS OF PRECIPITATION.
SHOWERS/THUNDERSTORMS ARE ALSO ACROSS MUCH OF CENTRAL AMERICA
ASSOCIATED WITH THE E PACIFIC MONSOON TROUGH THAT EXTENDS
THROUGH COSTA RICA AND PANAMA TO NORTHERN COLOMBIA. THE EASTERN
CARIBBEAN IS MOSTLY DRY AT THIS TIME DUE TO DRY AIR ALOFT.
EXPECT MOIST CONDITIONS TO REMAIN OVER THE WESTERN CARIBBEAN AS
THE WAVE AND UPPER LEVEL LOW MOVE WESTWARD.

THE ATLANTIC OCEAN...
BROAD SURFACE RIDGING COVERS THE ATLC ANCHORED BY A 1023 MB HIGH
NEAR 33N49W. AN AREA OF SHOWERS/THUNDERSTORMS IS ACROSS THE
BAHAMAS ASSOCIATED WITH AN UPPER LEVEL LOW S OF CUBA. A SECOND
UPPER LEVEL LOW CENTERED NEAR 32N50W IS SUPPORTING SCATTERED
SHOWERS/ISOLATED THUNDERSTORMS NEAR THE SURFACE HIGH CENTER FROM
30N-32N BETWEEN 48W-53W. AN UPPER TROUGH AXIS EXTENDING FROM THE
UPPER LOW CENTER TOWARDS THE SW IS HELPING SUPPORT ISOLATED
SHOWERS/THUNDERSTORMS FROM 20N-27N BETWEEN 58W-68W NEAR A
TROPICAL WAVE ALONG 36N63W TO 20N67W. THE REMAINDER OF THE
EASTERN ATLC IS MOSTLY DRY WITH AN UPPER LEVEL RIDGE COVERING
THE MAJORITY OF THE TROPICAL ATLC CENTERED NEAR 18N48W...AND A
BROAD UPPER LEVEL TROUGH OVER THE NE ATLC. VISIBLE SATELLITE
IMAGERY INDICATES THAT A BROAD AREA OF AFRICAN DUST EXTENDS
ACROSS THE ATLC AROUND T.D. SEVEN SUPPORTING FAIR CONDITIONS.

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

$$
WALTON





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