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Atlantic Tropical Weather Discussion (Text)

000
AXNT20 KNHC 300541
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0515 UTC.

...SPECIAL FEATURES...                                          
A 1012 MB LOW IS CENTERED NEAR 10N41W 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 07N-10N BETWEEN 42W-46W. PLEASE READ THE LATEST NHC 
TROPICAL WEATHER OUTLOOK UNDER AWIPS/WMO HEADERS MIATWOAT/ABNT20 
KNHC FOR MORE DETAILS.

...TROPICAL WAVES...                                     
TROPICAL WAVE EXTENDS FROM 06N23W TO 16N23W MOVING W AT 10-15 
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. CONVECTION REMAINS LIMITED DUE TO THE 
SAHARAN AIR LAYER COVERING MUCH OF THE TROPICAL ATLC...HOWEVER 
ISOLATED MODERATE CONVECTION IS FROM 04N-08N BETWEEN 22W-26W.

TROPICAL WAVE EXTENDS FROM 08N44W TO 18N44W MOVING W 15-20 KT. 
THE WAVE REMAINS TO THE WEST OF A 1012 MB SURFACE LOW CENTERED 
ALONG THE MONSOON TROUGH NEAR 09N41W. SATELLITE IMAGERY AND 
GLOBAL MODEL DATA AT 700 MB SEEM TO INDICATE THE WAVE MAY BE 
LOCATED A FEW DEGREES FARTHER WEST AND THIS IS NOTED ON THE 
METEOSAT SAHARAN AIR LAYER PRODUCT FROM CIMSS.

TROPICAL WAVE EXTENDS FROM 12N98W TO 22N97W MOVING W 15-20 KT. 
SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 15N-
19N BETWEEN 97W-100W. ISOLATED MODERATE CONVECTION IS FROM 20N-
22N BETWEEN 97W-99W.

...ITCZ/MONSOON TROUGH...                                     
THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 14N17W TO 
09N23W TO 10N38W TO A 1012 MB LOW PRES NEAR 10N41W TO 07N49W. 
ISOLATED MODERATE CONVECTION IS FROM 05N-09N BETWEEN 28W-32W.

...DISCUSSION...

GULF OF MEXICO...                                              
AN UPPER LEVEL TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER THE 
EASTERN CONUS THAT SUPPORTS A 1012 MB LOW CENTERED IN THE SW 
NORTH ATLC AND A COLD FRONT ANALYZED FROM THE LOW SW ACROSS THE 
NORTHERN FLORIDA PENINSULA AND INTO THE GULF NEAR 29N83W. THE 
COLD FRONT EXTENDS WESTWARD ALONG 29N 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 ALONG 27N IS PROVIDING FOCUS FOR ISOLATED 
SHOWERS AND TSTMS WITHIN 45 NM EITHER SIDE OF THE SURFACE 
TROUGH...AND FROM 24N-27N BETWEEN 82W-86W. OTHERWISE...A SURFACE 
RIDGE ANCHORED BY A 1018 MB HIGH CENTERED NEAR 27N95W PREVAILS 
ACROSS THE WESTERN GULF AND A NARROW EAST-WEST CORRIDOR FROM THE 
FLORIDA STRAITS TO THE SW GULF. LOOKING AHEAD...THE FRONTAL 
BOUNDARY IS FORECAST TO DRIFT SOUTH ACROSS THE EASTERN GULF 
WATERS THROUGH LATE WEDNESDAY 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 EVENING FOCUSED ON BOTH SIDES OF AN UPPER 
LEVEL LOW CENTERED OVER THE CENTRAL CARIBBEAN NEAR 16N80W. 
LINGERING WIDELY SCATTERED AFTERNOON AND EVENING SHOWERS AND  
TSTMS CONTINUE IN THE VICINITY OF THE WINDWARD PASSAGE. 
OTHERWISE...THE ONLY OTHER CONVECTION OCCURRING IS SCATTERED 
SHOWERS AND TSTMS ALONG THE COASTS OF COLOMBIA...PANAMA...AND 
COSTA RICA BETWEEN 75W-84W...DUE TO THE CLOSE PROXIMITY OF THE 
MONSOON TROUGH ANALYZED ALONG 07N/08N IN THE EAST PACIFIC 
REGION. 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 LINGERING ISOLATED SHOWERS AND TSTMS ARE OCCURRING 
ACROSS WESTERN PORTIONS OF THE ISLAND AND THE ADJACENT COASTAL 
WINDWARD PASSAGE WATERS. THIS ACTIVITY IS EXPECTED TO CONTINUE 
DIMINISHING DURING THE NEXT FEW HOURS. OTHERWISE...THE ISLAND 
REMAINS WITHIN SOUTHWESTERLY FLOW ALOFT AS AN UPPER LEVEL LOW IS 
CENTERED TO THE SW NEAR 16N80W. 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 
1012 MB LOW CENTERED OFF THE SE U.S. COAST NEAR 32N77W. A COLD 
FRONT EXTENDS SW FROM THE LOW CENTER TO THE NORTHERN FLORIDA 
PENINSULA NEAR 29N81W. TO THE SE OF THE FRONT...A PRE-FRONTAL 
SURFACE TROUGH EXTENDS FROM 31N75W TO 28N81W AND INTO THE GULF 
OF MEXICO. ISOLATED SHOWERS AND TSTMS ARE OCCURRING FROM 25N-31N 
BETWEEN 75W-80W. 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 ISOLATED SHOWERS AND TSTMS 
FROM 23N-28N BETWEEN 62W-67W. 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 36N54W. THE RIDGE 
AXIS EXTENDS SE FROM THE HIGH TO 30N50W TO 20N22W.

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

$$
HUFFMAN