000
AXNT20 KNHC 261135
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT THU JUL 26 2012

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.

...TROPICAL WAVES...

A 1012 MB LOW IS SW OF THE CAPE VERDE ISLANDS NEAR 13N29W MOVING 
W NEAR 20 KT. LOW IS EMBEDDED WITHIN AN AREA OF DEEP LAYER 
MOISTURE AS DEPICTED ON TOTAL PRECIPITABLE WATER IMAGERY. 
ISOLATED SHOWERS ARE WITHIN 90 NM OF THE LOW OVER THE NE 
SEMICIRCLE.  

MID ATLC TROPICAL WAVE EXTENDS FROM 23N43W TO 12N46W MOVING W 
NEAR 10 KT. WAVE IS ALONG THE LEADING EDGE OF A SURGE OF DEEP 
LAYER MOISTURE AS DEPICTED ON TOTAL PRECIPITABLE WATER IMAGERY. 
NO ASSOCIATED DEEP CONVECTION.

TROPICAL WAVE IS IN THE W CARIBBEAN EXTENDING FROM 21N83W TO 
13N84W MOVING W 20-25 KT. WAVE IS ALONG THE LEADING EDGE OF LOW 
AMPLITUDE SURGE OF DEEP LAYER MOISTURE AS DEPICTED ON TOTAL 
PRECIPITABLE WATER IMAGERY. SCATTERED SHOWERS/ISOLATED 
THUNDERSTORMS ARE WITHIN 75 NM OF LINE FROM 18N80W TO THE COAST 
OF HONDURAS NEAR 16N85W. 

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS W AFRICA INTO THE E TROPICAL 
ATLC NEAR 17N16W ALONG 15N23W THROUGH THE 1012 MB LOW CONTINUING 
TO 11N41W WHERE THE ITCZ CONTINUES ALONG 8N50W TO INLAND OVER 
SOUTH AMERICA NEAR 6N58W. CLUSTERS OF SCATTERED MODERATE/ 
ISOLATED STRONG CONVECTION ARE FROM 7N-10N BETWEEN 30W-37W AND 
WITHIN 120 NM N OF THE ITCZ BETWEEN 50W-59W. CLUSTERS OF 
SCATTERED MODERATE CONVECTION ARE WITHIN 120 NM ALONG THE COAST 
OF AFRICA FROM 9N-11N. 

...DISCUSSION...

GULF OF MEXICO...
AN UPPER RIDGE AXIS EXTENDS FROM NEAR TUXPAN MEXICO THROUGH AN 
UPPER HIGH NEAR 26N93W TO THE N GULF COAST NEAR THE FLORIDA/ 
ALABAMA BORDER. AN INVERTED UPPER TROUGH EXTENDS FROM THE 
CARIBBEAN THROUGH THE YUCATAN CHANNEL TO THE FLORIDA COAST NEAR 
CEDAR KEY SUPPORTING SURFACE TROUGH THAT EXTENDS FROM S GEORGIA 
ALONG 30N83W INTO THE GULF WATERS TO 27N84W WITH SCATTERED 
SHOWERS/ISOLATED THUNDERSTORMS N OF 28N BETWEEN 83W-85W. A 
SURFACE RIDGE EXTENDS FROM THE W ATLC ACROSS S FLORIDA TO NEAR 
25N90W. ISOLATED SHOWERS WITH POSSIBLE ISOLATED THUNDERSTORMS 
ARE OVER THE NW GULF N OF 24N W OF 91W LEAVING THE REMAINDER OF 
THE GULF WITH CLEAR SKIES THIS MORNING. SURFACE TROUGH WILL 
DISSIPATE TODAY AS THE ATLC SURFACE RIDGE BUILDS ACROSS THE GULF 
FROM CENTRAL FLORIDA TO NE TEXAS. THE W CARIBBEAN TROPICAL WAVE 
WILL MOVE W THROUGH THE BAY OF CAMPECHE FRI NIGHT/SAT.

CARIBBEAN SEA...
AN INVERTED UPPER TROUGH EXTENDS OVER THE NW CARIBBEAN FROM 
HONDURAS NEAR 16N88W THROUGH THE YUCATAN CHANNEL INTO THE GULF 
OF MEXICO. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE FROM 
18N-20N BETWEEN 74W-82W INCLUDING THE CAYMAN ISLANDS. AN UPPER 
RIDGE EXTENDS FROM THE TROPICAL ATLC OVER THE E CARIBBEAN E OF 
80W WITH DRY STABLE AIR E OF 70W LEAVING THE REMAINDER OF THE 
CARIBBEAN UNDER MOSTLY CLEAR SKIES THIS MORNING. SURFACE RIDGE 
OVER THE ATLC BASIN WILL CONTINUE TO PRODUCE FRESH TO STRONG 
EASTERLY TRADE WINDS ACROSS THE CENTRAL CARIBBEAN THROUGH MON. 
TROPICAL WAVE WILL MOVE THROUGH THE W CARIBBEAN BY FRI MORNING 
THEN OVER THE YUCATAN PENINSULA. MID ATLC TROPICAL WAVE WILL 
MOVE INTO NE CARIBBEAN SAT AND SUN. 

ATLANTIC OCEAN...
AN UPPER RIDGE COVERS THE FAR W ATLC ANCHORED OFF THE COAST OF 
THE CAROLINAS COVERING THE AREA W OF 70W. AN UPPER TROUGH COVERS 
THE REMAINDER OF THE W ATLC INTO THE CENTRAL ATLC SUPPORTING A 
COLD FRONT THAT ENTERS THE REGION AT 26/0900 UTC E OF BERMUDA 
NEAR 32N62W ALONG 29N68W TO 30N70W WHERE IT PULLS UP STATIONARY 
AS IT CONTINUES OUT OF THE REGION NEAR 32N75W. SCATTERED 
SHOWERS/THUNDERSTORMS ARE WITHIN 120 NM SE OF THE COLD FRONT E 
OF 70W WITH ISOLATED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS 
OVER THE REMAINDER OF THE AREA N OF 26N BETWEEN 52W-70W AND N OF 
28N BETWEEN 70W-77W. AN UPPER LOW IS OVER THE NE ATLC NEAR THE 
AZORES WITH A COLD FRONT N OF THE DISCUSSION AREA AND A SURFACE 
TROUGH EXTENDING THROUGH 32N28W TO 29N34W. THE REMAINDER OF THE 
ATLC IS DOMINATED BY SURFACE RIDGE AXIS EXTENDING FROM THE 
E/CENTRAL ATLC NEAR 32N43W ALONG 24N64W THEN W ACROSS S FLORIDA 
INTO THE GULF OF MEXICO. W ATLC COLD FRONT WILL WEAKEN TONIGHT 
THEN DISSIPATE BY FRI EVENING. SURFACE RIDGE WILL SHIFT N FRI 
THROUGH SUN REACHING ALONG 28N BY MON.

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

$$
PAW