[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 261750
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT TUE JUL 26 2011

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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1745 UTC.

...SPECIAL FEATURE...

A TROPICAL WAVE MOVES ACROSS THE NW CARIBBEAN ANALYZED FROM
25N83W ACROSS FAR WEST CUBA TO 20N85W INTO CENTRAL AMERICA
ACROSS EASTERN HONDURAS AND NICARAGUA NEAR 13N84W. VISIBLE
SATELLITE IMAGERY INDICATES BROAD CYCLONIC TURNING OF THE
LOW-MID LEVEL CLOUD FIELD IN THE VICINITY OF THE WAVE AXIS. THIS
SYSTEM HAVE BECOME A LITTLE BETTER ORGANIZED OVER THE PAST 6
HOURS. HOWEVER...THE SYSTEM DOES NOT HAVE A CLOSED CIRCULATION
AT THIS TIME. ADDITIONAL SLOW DEVELOPMENT OF THIS SYSTEM IS
POSSIBLE DURING THE NEXT COUPLE OF DAYS. TOTAL PRECIPITABLE
WATER IMAGERY ALSO SHOWS A LARGE AREA OF ENHANCED DEEP LAYER
MOISTURE ACROSS THE NW CARIBBEAN. SCATTERED MODERATE TO HEAVY
SHOWERS AND THUNDERSTORMS ARE OCCURRING FROM 17N-24N BETWEEN
79W-85W. BRIEF PERIODS OF LOCALLY HEAVY RAINFALL AND GUSTY WINDS
ARE EXPECTED OVER WESTERN CUBA AS THE SYSTEM MOVES WNW OVER THE
NEXT 24 HOURS. THIS ACTIVITY COULD GENERATE FLASH FLOODING AND
MUDSLIDES OVER SATURATED-HIGH TERRAIN AND RIVERS DURING THE
FORECAST PERIOD.

...TROPICAL WAVES...

A TROPICAL WAVE IS IN THE EAST TROPICAL ATLC ANALYZED FROM
16N20W TO 9N23W MOVING W AT ABOUT 10 KT. THE WAVE AND ASSOCIATED
CONVECTION IS EMBEDDED IN A REGION OF DEEP MOISTURE ASSOCIATED
TO THE MONSOON TROUGH.

A TROPICAL WAVE IS APPROACHING THE LESSER ANTILLES ISLANDS...
ANALYZED FROM 19N54W TO 11N55W MOVING W AT 10-15 KT. VISIBLE
SATELLITE IMAGERY AND DERIVED WINDS INDICATE BROAD CYCLONIC
LOW-LEVEL FLOW IN THE VICINITY OF THE WAVE AXIS. THIS WAVE IS
EMBEDDED WITHIN A DEEP MOISTURE SURGE ON TOTAL PRECIPITABLE
WATER IMAGERY. SCATTERED WEAK SHOWERS ARE WITHIN 150-300 NM ON
EITHER SIDE OF THE AXIS.

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

THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST OF MAURITANIA
NEAR 18N16W TO 16N19W. THEN...IT RESUMES SW OF A TROPICAL WAVE
NEAR 9N25W TO 7N30W TO 7N36W. THE ITCZ AXIS CONTINUES FROM THIS
POINT TO 9N43W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION
IS FROM 7N-15N E OF 28W. THIS AREA OF CONVECTION IS ALSO
ASSOCIATED WITH THE TROPICAL WAVE DISCUSSED ABOVE. A SURFACE
TROUGH IS EMBEDDED IN THE EXTREME WEST PORTION OF THE ITCZ
ANALYZED FROM 11N44W TO 5N45W. SCATTERED WEAK TO MODERATE
CONVECTION IS WITHIN 60 NM ON EITHER SIDE OF THE TROUGH AXIS.

...DISCUSSION...

THE GULF OF MEXICO...
NE FLOW ALOFT WITH LIMITED MOISTURE IN THE MID LEVELS OF THE
ATMOSPHERE COVER MUCH OF THE GULF ON WATER VAPOR IMAGERY...
EXCEPT OVER THE BAY OF CAMPECHE WHERE AN UPPER CYCLONIC
CIRCULATION LINGER NEAR 21N94W. THE LOWER LEVELS REMAIN FAIRLY
DRY ON TOTAL PRECIPITABLE WATER PRODUCT. THIS ENVIRONMENT ONLY
ALLOWS FOR ISOLATED LOW TOP SHOWERS DOTTING THE GULF THIS
AFTERNOON. STRONGER CONVECTION IS FOUND OVER THE NORTHERN
GULF...AFFECTING THE COASTAL WATERS FROM TEXAS TO THE FLORIDA
PANHANDLE INDICATED BY DOPPLER RADAR IMAGERY SHOWING SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS WITHIN 40-70 NM ALONG THE
NORTHERN COAST STATES BETWEEN 83W-94W. THIS AREA OF CONVECTION
IS ASSOCIATED TO A MID LEVEL TROUGH EXTENDING ACROSS THE SE
CONUS. THE ACTIVITY IS EXPECTED TO LINGER OVER THE NEXT 24
HOURS. THE NORTHERN EXTENSION OF A TROPICAL WAVE REACHES THE SE
GULF WITH NO CONVECTION AT THE TIME. HOWEVER...COMPUTER MODELS
INDICATE THIS SYSTEM WILL BEGIN TO BRING CONVECTION TO THE
FLORIDA STRAITS AND SE GULF INCLUDING THE YUCATAN CHANNEL
WITHIN THE NEXT 6 HOURS.

THE CARIBBEAN SEA...
A TROPICAL WAVE IS MOVING ACROSS THE NW CARIBBEAN WITH AXIS
CROSSING WESTERN CUBA INTO EASTERN HONDURAS. THIS WAVE IS
GENERATING SCATTERED HEAVY SHOWERS AND THUNDERSTORMS OVER THE
WATERS N OF 17N BETWEEN 79W-85W INCLUDING INLAND PORTIONS CUBA.
BRIEF PERIODS OF LOCALLY HEAVY RAINFALL AND GUSTY WINDS ARE
EXPECTED AS THE SYSTEM MOVES WNW OVER THE NEXT 24 HOURS...WITH
THE CONVECTION EXPECTED TO REACH THE YUCATAN CHANNEL WITHIN THE
NEXT 6 HOURS. THIS ACTIVITY COULD GENERATE FLASH FLOODING AND
MUDSLIDES OVER SATURATED-HIGH TERRAIN AND RIVERS DURING THE
FORECAST PERIOD. SIMILAR ACTIVITY IS OVER THE FAR SW BASIN...
WITHIN 70 NM OFF THE COAST OF COSTA RICA AND PANAMA...DUE TO
CLOSE PROXIMITY TO THE MONSOON TROUGH ANALYZED ACROSS CENTRAL
AMERICA THROUGH SOUTHERN NICARAGUA INTO NORTHERN COLOMBIA. A
SURFACE TROUGH MOVES ACROSS THE EASTERN BASIN WITH AXIS ANALYZED
FROM 17N64W TO 13N65W. SCATTERED WEAK SHOWERS ARE WITHIN 60-120
NM ON EITHER SIDE OF THE TROUGH AXIS. FAIR WEATHER CONDITIONS
ARE ELSEWHERE ACROSS THE REMAINDER OF THE CARIBBEAN WITH
EASTERLY 10-20 KT TRADE WINDS.

THE ATLANTIC OCEAN...
A BROAD SURFACE RIDGE DOMINATES THE ATLC DISCUSSION AREA WITH
MOSTLY FAIR WEATHER CONDITIONS...ANCHORED BY A BROAD AND STRONG
1029 MB HIGH CENTERED N OF THE AZORES NEAR 40N27W. THIS HIGH
PRESSURE SYSTEM EXTENDS A RIDGE AXIS WEST-SOUTHWEST ACROSS THE
DISCUSSION AREA REACHING THE FAR W ATLC TO THE NORTHERN BAHAMAS.
HOWEVER...SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE
WITHIN 100-130 NM OFF THE EASTERN COAST OF THE FLORIDA PENINSULA
GENERATED BY DIFFLUENCE FLOW IN THE UPPER LEVELS...BETWEEN THE
UPPER TROUGH OVER THE SE CONUS AND THE UPPER ANTICYCLONIC
CIRCULATION OVER THE FAR W ATLC. AN UPPER LEVEL CYCLONIC
CIRCULATION IS OVER THE CENTRAL ATLC NEAR 25N50W WITH NO
ASSOCIATED DEEP CONVECTION.

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

$$

GARCIA




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