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Atlantic Tropical Weather Discussion (Text)

000
AXNT20 KNHC 301045
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT WED JUL 30 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 
1015 UTC.

...SPECIAL FEATURES...                                          
A 1012 MB LOW IS CENTERED NEAR 10N43W MOVING W-NW AT 15 KT. THE 
LOW LIES WITHIN THE MONSOON TROUGH AXIS AND CONTINUES TO SHOW AN 
IMPRESSIVE SATELLITE PRESENTATION...HOWEVER LACKS ANY ORGANIZED 
SIGNIFICANT DEEP CONVECTION. ISOLATED MODERATE CONVECTION IS 
FROM 06N-10N BETWEEN 43W-47W. PLEASE SEE THE LATEST NHC TROPICAL 
WEATHER OUTLOOK UNDER AWIPS/WMO HEADERS MIATWOAT/ABNT20 KNHC FOR 
MORE DETAILS.

...TROPICAL WAVES...                                     
TROPICAL WAVE EXTENDS FROM 10N25W TO 17N26W MOVING W AT 15 KT. A 
BROAD LOW-LEVEL...850 MB-700 MB...CYCLONIC CIRCULATION IS NOTED 
IN THE VICINITY OF THE WAVE AND ACROSS AN AREA TO THE WEST OF 
THE WAVE AXIS ALONG THE MONSOON TROUGH. THIS AREA ALSO COINCIDES 
WITH A BROAD AREA OF 850 MB RELATIVE VORTICITY FROM 08N-11N 
BETWEEN 20W-29W. IN ADDITION...A 1012 MB LOW IS CENTERED AT THE 
SOUTHERN EXTENT OF THE WAVE WHICH REMAINS EMBEDDED WITHIN THE 
MONSOON TROUGH. CONVECTION REMAINS LIMITED DUE TO THE SAHARAN 
AIR LAYER COVERING MUCH OF THE TROPICAL ATLC...HOWEVER ISOLATED 
MODERATE CONVECTION IS FROM 05N-08N BETWEEN 23W-27W.

TROPICAL WAVE EXTENDS FROM 10N48W TO 19N51W MOVING W AT 15-20 
KT. THE WAVE REMAINS TO THE W-NW OF A 1012 MB SURFACE LOW 
CENTERED ALONG THE MONSOON TROUGH NEAR 10N43W. SATELLITE IMAGERY 
AND GLOBAL MODEL DATA INDICATE THE WAVE IS WITHIN A 700 MB 
TROUGH THAT HAS MOVED WEST OF THE LOW EMBEDDED WITHIN THE 
MONSOON TROUGH. THE WAVE REMAINS WITHIN THE SAHARAN AIR LAYER 
AND STABLE CONDITIONS ALOFT ARE INHIBITING ANY SIGNIFICANT DEEP 
CONVECTION AT THIS TIME.

...ITCZ/MONSOON TROUGH...                                     
THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 18N16W TO 
14N19W TO 1012 MB LOW PRES NEAR 10N25W TO 09N29W TO 11N39W TO A 
1012 MB LOW PRES NEAR 10N43W TO 07N47W. THE INTERTROPICAL 
CONVERGENGE ZONE AXIS EXTENDS FROM 07N47W TO 06N54W. WIDELY 
SCATTERED MODERATE CONVECTION IS FROM 06N-09N BETWEEN 11W-
15W...AND FROM 05N-08N BETWEEN 29W-34W.

...DISCUSSION...

GULF OF MEXICO...                                              
AN UPPER LEVEL TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER THE 
EASTERN CONUS THAT SUPPORTS A COLD FRONT ANALYZED ACROSS THE 
NORTHERN FLORIDA PENINSULA AND INTO THE GULF NEAR 29N83W. THE 
COLD FRONT EXTENDS SW TO 27N87W TO 28N91W AND BECOMES STATIONARY 
TO THE TEXAS COAST NEAR GALVESTON BAY. THE FRONT REMAINS FAIRLY 
PRECIPITATION FREE...HOWEVER A PRE-FRONTAL SURFACE TROUGH 
ANALYZED TO THE SOUTH OF THE FRONT FROM THE TAMPA BAY REGION 
NEAR 28N82W TO 26N89W IS PROVIDING FOCUS FOR ISOLATED SHOWERS 
AND TSTMS WITHIN 45 NM EITHER SIDE OF THE COLD FRONT AND SURFACE 
TROUGH. OTHERWISE...A SURFACE RIDGE ANCHORED BY A PAIR OF 1018 
MB HIGHS CENTERED NEAR 27N94W AND 23N84W PREVAIL ACROSS THE 
WESTERN AND SE GULF MAINTAINING FAIR CONDITIONS AND MOSTLY CLEAR 
SKIES THIS MORNING. LOOKING AHEAD...THE FRONTAL BOUNDARY IS 
FORECAST TO DRIFT SOUTH ACROSS THE EASTERN GULF WATERS TODAY AND 
GRADUALLY BECOME DIFFUSE ON THURSDAY. MEANWHILE...WEAK RIDGING 
IS EXPECTED TO REMAIN ACROSS THE WESTERN AND CENTRAL GULF 
THROUGH FRIDAY.

CARIBBEAN SEA...                                       
RELATIVELY DRY AND STABLE CONDITIONS ALOFT ARE NOTED OVER MUCH 
OF THE CARIBBEAN THIS MORNING FOCUSED ON BOTH SIDES OF AN UPPER 
LEVEL LOW CENTERED OVER THE CENTRAL CARIBBEAN NEAR 18N78W. A FEW 
ISOLATED SHOWERS AND TSTMS ARE OCCURRING ACROSS THE ADJACENT 
COASTAL WATERS BETWEEN EASTERN CUBA AND JAMAICA...OTHERWISE... 
THE ONLY OTHER CONVECTION OCCURRING IS SCATTERED SHOWERS AND 
TSTMS ALONG THE COASTS OF COLOMBIA...PANAMA...AND COSTA RICA 
BETWEEN 76W-84W...AND WIDELY SCATTERED SHOWERS AND TSTMS 
OCCURRING EAST OF THE LEEWARD ISLANDS FROM 12N-17N BETWEEN 58W-
62W. FINALLY...MODERATE TO FRESH TRADES PERSIST WITH SLIGHTLY 
STRONGER WINDS IN THE RANGE OF 20-25 KT IN CLOSE PROXIMITY TO 
THE COAST OF COLOMBIA.

...HISPANIOLA...                                        
CURRENTLY...THE ISLAND REMAINS WITHIN SOUTHWESTERLY FLOW ALOFT 
AS AN UPPER LEVEL LOW IS CENTERED TO THE W-SW NEAR 18N78W. GIVEN 
THE OVERALL DIFFLUENT ENVIRONMENT IN PLACE...SCATTERED SHOWERS 
AND TSTMS ARE FORECAST WEDNESDAY AFTERNOON INTO THE EVENING WITH 
PEAK DAYTIME HEATING AND INSTABILITY.

ATLANTIC OCEAN...                                              
AN UPPER LEVEL TROUGH IS OVER THE EASTERN CONUS THAT SUPPORTS A 
COLD FRONT EXTENDING INTO THE DISCUSSION AREA NEAR 32N76W THEN 
SW TO THE NORTHERN FLORIDA PENINSULA NEAR 29N81W. TO THE SE OF 
THE FRONT...A PRE-FRONTAL SURFACE TROUGH EXTENDS FROM 29N79W TO 
THE FLORIDA STRAITS NEAR 24N81W. SCATTERED SHOWERS AND TSTMS ARE 
OCCURRING PRIMARILY SOUTH OF THE FRONTAL BOUNDARY AND EAST OF 
THE SURFACE TROUGH FROM 25N-32N BETWEEN 73W-79W. FARTHER EAST... 
AN UPPER LEVEL LOW IS CENTERED NEAR 25N66W WITH MID-LEVEL ENERGY 
FOCUSED NEARLY IN THE SAME LOCATION THAT SUPPORTS AN AREA OF 
WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS FROM 22N-28N BETWEEN 
62W-68W. OTHERWISE...THE REMAINDER OF THE CENTRAL AND EASTERN 
ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 
1028 MB HIGH CENTERED NEAR 37N54W. THE RIDGE AXIS EXTENDS SE 
FROM THE HIGH TO 30N50W TO 22N30W.

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

$$
HUFFMAN