000
AXPZ20 KNHC 042200
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SUN JUL 04 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2145 UTC.

...ITCZ...
AXIS IS ALONG 11N86W TO 09N105W TO 09N125W TO 10N140W. SCATTERED 
MODERATE ISOLATED STRONG WITHIN 120 NM S OF AXIS W OF 131W. 
SCATTERED MODERATE WITHIN 90-120 NM EITHER SIDE OF THE AXIS 
BETWEEN 107W AND 120W...AND WITHIN 120 NM S OF THE AXIS BETWEEN 
94W AND 100W. 

...TROPICAL WAVE...
TROPICAL WAVE N OF 08N ALONG 86W MOVING W AT 15 KT AS AVERAGED 
OVER THE PAST 24 HOURS. SCATTERED MODERATE TO ISOLATED STRONG 
CONVECTION FROM 5N-10N BETWEEN 81W-87W.

...DISCUSSION...
EXPANSIVE UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED NEAR 
24N129W DOMINATED MOST OF THE DISCUSSION AREA W OF 110W. 
ASSOCIATED RIDGE AXIS EXTENDS EWD ACROSS BAJA CALIFORNIA INTO 
NORTHERN MEXICO TO ANOTHER SMALLER ANTICYCLONE OVER CENTRAL 
TEXAS. RIDGE ALSO EXTENDS WWD TO JUST S OF HAWAII. A VAST AREA 
OF STRONG DEEP LAYERED SUBSIDENCE/DRY AIR COVERS THE AREA N OF 
20N W OF 110W. AN AREA OF STRONG CONVECTION WAS ERUPTING NEAR 
THE RIO GRANDE VALLEY AND EXTREME NRN MEXICO IN ASSOCIATION WITH 
THE REMNANTS OF FORMER TROPICAL CYCLONE ALEX. MID TO UPPER LEVEL 
CONVECTIVE DEBRIS MOISTURE WAS BEING ADVECTED TO THE W AND SW 
OVER MEXICO AND THE TROPICAL PACIFIC E OF 130W BY STRONG UPPER 
LEVEL NE TO E WINDS TO THE S OF THE RIDGE AXIS. 

A NARROW UPPER LEVEL TROUGH/SHEAR AXIS EXTENDS FROM THE WRN GULF 
OF MEXICO ACROSS SOUTHERN MEXICO TO 12N105W. UPPER LEVEL 
DIFFLUENT FLOW IS ENHANCING CONVECTIVE ACTIVITY ALONG THE ITCZ 
SE OF THE TROUGH BETWEEN 85W AND 100W IN AN AREA OF MODERATE TO 
STRONG ELY FLOW AT THE UPPER LEVELS. 

AT THE SURFACE A 1035 MB HIGH NEAR 42N140W WITH A WEAK SURFACE 
RIDGE EXTENDING SE ACROSS THE DISCUSSION AREA ALONG 30N133W TO 
20N110W. THE GRADIENT BETWEEN THE RIDGE AND LOWER PRESSURES OVER 
THE INTERMOUNTAIN AND SW CONUS HAS RELAXED TO THE POINT THAT 
WINDS ARE LESS THAN 20 KT OVER THE AREA N OF 20N. THIS OVERALL 
PATTERN IS EXPECTED TO PERSIST THROUGH 48 HOURS.  

LONG PERIOD S-SW SWELL TRAIN FROM SRN HEMISPHERE HAS SPREAD 
NORTHWARD THROUGH NEARLY THE ENTIRE DISCUSSION AREA WITH OVERALL 
WAVE PERIODS DECREASING AND THE THREAT FOR LARGE BREAKING WAVES 
AND DANGEROUS SURF CONDITIONS ALONG EXPOSED SHOALS...REEFS AND 
BEACHES IS GRADUALLY EASING. THE S SWELL IS EXPECTED TO SUBSIDE 
BY TUE WITH N TO NE SWELL ENTERING THE FAR NW PORTION OF THE 
MARINE FORECAST AREA BY THEN. 

$$
COBB