Tropical Weather Discussion
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000
AXNT20 KNHC 041024
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT TUE AUG 04 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1015 UTC.

...SPECIAL FEATURES...

GALE FORCE WINDS ARE FORECAST TO CONTINUE THROUGH THIS MORNING
UNTIL 1800 UTC FROM 11N TO 13N BETWEEN 74W AND 77W. THESE WINDS
ARE ASSOCIATED WITH THE TIGHT PRESSURE GRADIENT BETWEEN THE W
ATLANTIC SURFACE RIDGE AND A 1006 MB LOW CENTERED OVER N
COLOMBIA. PLEASE SEE THE HIGH SEAS FORECAST UNDER AWIPS/WMO
HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS.

...TROPICAL WAVES...

A TROPICAL WAVE IS OVER THE EASTERN ATLANTIC WITH AN AXIS
EXTENDING FROM 18N36W TO 09N37W MOVING W AT AROUND 10 KT OVER
THE PAST 24 HOURS. MODEL GUIDANCE INDICATES 700 MB TROUGHING
FROM 34W TO 39W. SSMI TPW SHOWS THE WAVE AT THE LEADING EDGE OF
A POLEWARD SURGE IN TROPICAL MOISTURE. NO DEEP CONVECTION IS
ASSOCIATED WITH THIS WAVE.

A TROPICAL WAVE IS OVER THE CENTRAL ATLANTIC WITH AXIS EXTENDING
FROM 20N48W TO 10N48W...MOVING W AT 10 TO 15 KT OVER THE PAST 24
HOURS. THIS WAVE COINCIDES WITH BROAD 700 MB TROUGHING BETWEEN
45W AND 53W. SSMI TPW IMAGERY SHOWS A DRY ENVIRONMENT
SURROUNDING THIS WAVE N OF 13N ALONG WITH SAHARAN DUST INDICATED
BY METEOSAT IMAGERY. A MOIST ENVIRONMENT IS INDICATED S OF 13N.
NO DEEP CONVECTION IS NOTED WITH THIS WAVE.

A TROPICAL WAVE IS OVER THE WESTERN CARIBBEAN WITH AN AXIS
EXTENDING FROM THE WINDWARD PASSAGE AT 20N78W TO 10N79W MOVING W
AT 15 KT OVER THE PAST 24 HOURS. THIS WAVE COINCIDES WITH 700 MB
TROUGHING BETWEEN 76W AND 81W. ISOLATED MODERATE CONVECTION IS
FROM 18N TO 22N BETWEEN 75W AND 82W.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA TO THE E TROPICAL
ATLANTIC NEAR 11N15W TO 11N35W AND RESUMES W OF A TROPICAL WAVE
NEAR 11N39W TO 10N46W. THE ITCZ EXTENDS W OF A TROPICAL WAVE
NEAR 10N49W TO S AMERICA NEAR 10N62W. CLUSTERS OF MODERATE
CONVECTION ARE FROM 05N TO 14N BETWEEN 13W AND 21W...WHICH MAY
ALSO BE ASSOCIATED WITH A TROPICAL WAVE ABOUT TO EMERGE OFF THE
AFRICAN COAST. ISOLATED MODERATE CONVECTION IS ELSEWHERE WITHIN
200 NM OF THE MONSOON TROUGH AND ITCZ AXIS.

...DISCUSSION...

GULF OF MEXICO...

AN UPPER RIDGE EXTENDS FROM TX TO THE NW GULF WITH AN AXIS THAT
EXTENDS E ACROSS N FL. THE UPPER LEVEL DIFFLUENCE ASSOCIATED
WITH THE UPPER RIDGE AXIS AND MODERATE MOISTURE SUPPORTS
ISOLATED MODERATE CONVECTION FROM 26N TO 30N BETWEEN 86W AND
93W. AN UPPER TROUGH EXTENDS NE FROM THE NW CARIBBEAN TO CENTRAL
CUBA AND SUPPORTS ISOLATED THUNDERSTORMS OVER THE FL STRAITS. AT
THE SURFACE...A SURFACE RIDGE OVER THE W ATLC EXTENDS AN AXIS
ACROSS S FL AND THE CENTRAL GULF. SE WINDS AROUND 10 KT COVER
THE S GULF. S TO SW WINDS AROUND 10 KT COVER THE N GULF. A
SURFACE TROUGH OVER THE SOUTHERN US WILL NEAR THE NE GULF COAST
TODAY...ENHANCING CHANCES FOR CONVECTION OVER THAT PORTION OF
THE GULF BASIN.

CARIBBEAN SEA...

GALE-FORCE WINDS ARE NEAR THE COAST OF N COLOMBIA. PLEASE SEE
THE SPECIAL FEATURES SECTION FOR MORE DETAILS. STRONG TRADE
WINDS ARE OVER THE REMAINDER OF THE S CENTRAL CARIBBEAN.
MODERATE TO FRESH TRADE WINDS ARE ELSEWHERE OVER THE CARIBBEAN.
A TROPICAL WAVE IS OVER THE WESTERN CARIBBEAN. PLEASE SEE THE
TROPICAL WAVES SECTION FOR MORE DETAILS. AN UPPER TROUGH THAT
EXTENDS ACROSS THE NW CARIBBEAN IS INTERACTING WITH A MODERATELY
MOIST AIRMASS TO SUPPORT ISOLATED MODERATE CONVECTION FROM 15N
TO 21N BETWEEN 82W AND 87W. THE REMAINDER OF THE CARIBBEAN IS
FREE OF DEEP CONVECTION THIS MORNING. CONVECTION WILL CONTINUE
OVER THE NW CARIBBEAN TODAY.

...HISPANIOLA...

DRY AIR AT THE MID TO UPPER LEVELS IS SPREADING ACROSS THE
ISLAND THIS MORNING AS A TROPICAL WAVE AND UPPER TROUGH W OF THE
AREA CONTINUES TO MOVE FARTHER FROM HISPANIOLA. PRECIPITATION
TODAY WILL BE FROM WEAK SHOWERS IN THE TRADE WIND FLOW OVER THE
EASTERN DOMINICAN REPUBLIC...AND ISOLATED THUNDERSTORMS OVER THE
ISLAND DUE TO TERRAIN IN THE AFTERNOON.

ATLANTIC OCEAN...

A MID TO UPPER LEVEL TROUGH EXTENDS FROM THE NW CARIBBEAN TO THE
CENTRAL BAHAMAS. A SURFACE TROUGH IS LOCATED UNDER THE TROUGHING
ALOFT AND EXTENDS FROM 26N76W TO 22N78W. SCATTERED MODERATE
CONVECTION IS FROM 23N TO 27N BETWEEN 72W AND 78W. ANOTHER
SURFACE TROUGH IS OVER THE W ATLC FROM 31N68W TO 28N70W
SUPPORTING ISOLATED MODERATE CONVECTION WITHIN 100 NM OF THE
TROUGH AXIS. SURFACE RIDGING ANCHORED BY A 1027 MB HIGH CENTERED
NEAR 35N53W DOMINATES THE CENTRAL AND EASTERN SUBTROPICAL ATLC.
TWO TROPICAL WAVES ARE OVER THE TROPICAL ATLC. PLEASE REFER TO
THE TROPICAL WAVES SECTION FOR MORE DETAILS. CONVECTION IS
EXPECTED TO CONTINUE THROUGH TODAY FROM THE CENTRAL BAHAMAS
NORTHWARD TO 31N W OF 72W.

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

$$
LATTO


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