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Atlantic Tropical Weather Discussion (Text)

000
AXNT20 KNHC 241204
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT THU JUL 24 2014

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1115 UTC.

...SPECIAL FEATURES...                                          
A STRENGTHENING PRESSURE GRADIENT ACROSS THE SW CARIBBEAN SEA IS 
PRODUCING MINIMAL GALE FORCE NE TO E WINDS FROM 11N-13N BETWEEN 
73W-77W. WINDS ARE EXPECTED DROP BELOW GALE FORCE BY LATER THIS 
MORNING. SEE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO 
HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS.

...TROPICAL WAVES...                                     
TROPICAL WAVE EXTENDS FROM 3N45W TO 12N44W MOVING W AT 15-20 KT. 
THE WAVE APPEARS TO BE A POTENTIAL VORTICITY MAX ALONG A BROADER 
700 MB TROUGH AXIS. THE WAVE REMAINS SOUTH OF LOW LEVEL EASTERLY 
JET N OF 9N LARGELY EMBEDDED WITHIN THE SAHARAN AIR LAYER ACROSS 
THE TROPICAL ATLC. AS A RESULT...CONVECTION REMAINS SUPPRESSED N 
OF 10N WITH ISOLATED MODERATE CONVECTION OCCURRING FROM 5N-10N 
BETWEEN 45W-49W.

TROPICAL WAVE EXTENDS FROM 12N62W TO 19N59W MOVING W AT 20-25 
KT. THE WAVE ALSO THE REMNANTS OF TROPICAL DEPRESSION TWO AND 
INCORPORATES THE NORTHERN POTENTIAL VORTICITY MAX OF A 700 MB 
TROUGH. WIDELY SCATTERED MODERATE CONVECTION IS FROM 14N-16N 
BETWEEN 58W-67W...INCLUDING A PORTION OF THE LESSER ANTILLES. A 
LARGE AREA OF SAHARAN DUST FOLLOWS E OF THE WAVE WITH LEADING 
EDGE NOTED E OF 57W.

TROPICAL WAVE MOVING THROUGH S MEXICO EXTENDS S OF 20N ALONG 
96W. SCATTERED MODERATE CONVECTION FROM 18N-20N BETWEEN 93W-96W.

...ITCZ/MONSOON TROUGH...                                     
MONSOON TROUGH EXTENDS FROM LOW PRESSURE ALONG THE AFRICAN COAST 
NEAR 20N16W TO 10N24W. INTERTROPICAL CONVERGENCE ZONE AXIS 
EXTENDS FROM 10N24W TO 09N39W TO 02N51W. EXCEPT FOR CONVECTION 
ASSOCIATED WITH TROPICAL WAVES...THERE IS MINIMAL CONVECTION 
ALONG THE BOUNDARY THIS MORNING.

...DISCUSSION...

GULF OF MEXICO...                                               
A WEAKENING UPPER LEVEL LOW IS CENTERED OVER SOUTHERN LOUISIANA 
NEAR 30N92W. STATIONARY FRONT AND AN EMBEDDED SURFACE LOW ALONG 
THE NORTHERN GULF COAST ANALYZED EARLIER IS NO LONGER EVIDENT. A 
BROAD SURFACE RIDGE EXTENDS FROM CENTRAL FLORIDA W-SW TO 25N90W 
TO EAST-CENTRAL MEXICO NEAR 22N98W. LITTLE CHANGE IS EXPECTED 
DURING THE NEXT 24 HOURS. THE RIDGE WILL SLOWLY SHIFT NORTHWARD 
TO ANCHOR ROUGHLY ALONG 27N THROUGH THE WEEKEND.

CARIBBEAN SEA...                                               A 
A WEAK UPPER LEVEL LOW CENTERED OVER NW CUBA NEAR 21N84W. MOST 
OF THE MIDDLE TO UPPER LEVEL MOISTURE REMAINS OVER THE WESTERN 
CARIBBEAN. AN UPPER LEVEL RIDGE IS CENTERED NEAR 18N71W. WATER 
VAPOR IMAGERY INDICATES THIS UPPER LEVEL FEATURE REMAINS DRY AND 
SUBSIDENT PROVIDING MOSTLY FAIR CONDITIONS ACROSS NE CARIBBEAN 
INCLUDING HISPANIOLA...PUERTO RICO...AND THE LEEWARD ISLANDS. ON 
SOUTHERN PERIPHERY OF THE RIDGE...A NARROW BAND OF SHOWERS AND 
THUNDERSTORMS IS OCCURRING FROM 14N-16N BETWEEN 60W-70W. MOST OF 
THIS IS A WESTWARD EXTENSION OF REMNANTS OF TROPICAL DEPRESSION 
TWO NOW CLASSIFIED AS A TROPICAL WAVE ALONG 60W. THE WAVE WILL 
MOVE WEST AND INCREASE RAIN CHANCES IN THE LESSER ANTILLES THIS 
MORNING. FRESH TO STRONG TRADES ARE EXPECTED TO PERSIST ACROSS 
MUCH OF THE CARIBBEAN S OF 17N THROUGH THE REMAINDER OF THE WEEK.

...HISPANIOLA...                                                
CURRENT CONDITIONS REMAIN FAIR THIS EVENING FROM MODERATELY DRY 
AIR ALOFT RELATED TO UPPER LEVEL RIDGE CENTERED OVER THE ISLAND 
NEAR 18N71W. MOSTLY FAIR CONDITIONS ARE EAST OF THE ISLAND AS 
WELL. A TROPICAL WAVE THE REMNANTS OF T.D. TWO IS EXPECTED TO 
BRING WIDESPREAD PRECIPITATION LATE TONIGHT AND EARLY FRIDAY.

ATLANTIC OCEAN...                                              
UPPER LEVEL ANTICYCLONE IS CENTERED OVER THE SW NORTH ATLC NEAR 
30N75W. SURFACE RIDGE AXIS EXTENDS FROM PAIR OF 1024 MB HIGHS 
NEAR 30N33W AND 29N47W ALONG 28N TO CENTRAL FLORIDA NEAR 27N80W. 
MOSTLY FAIR SKIES AND FAIRLY BENIGN CONDITIONS PREVAIL ACROSS 
NEARLY ALL OF THE OCEANIC AREA EXCEPT IN IMMEDIATE VICINITY OF 
THE TROPICAL WAVES NOTED ABOVE NEAR THE LESSER ANTILLES AND IN 
CENTRAL ATLC ALONG 44W. A LARGE PORTION OF CENTRAL AND EASTERN 
TROPICAL ATLC IS UNDER THE INFLUENCE OF SAHARAN DUST STRETCHING 
MOSTLY NORTH OF 10N AND EAST OF 55W.

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

$$
MUNDELL