000
AXPZ20 KNHC 301547
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED JUN 30 2010

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...TROPICAL LOWS....

THE REMNANT LOW PRES OF CELIA IS ANALYZED NEAR 16N124W ON THE 
1200 UTC SURFACE MAP WITH AN ESTIMATED CENTRAL PRES OF 1010 MB. 
WINDS ARE 20 TO 25 KT WITHIN ABOUT 150 NM NW OF CENTER. A SWIRL 
OF LOW CLOUDS IS ASSOCIATED WITH THIS LOW WHICH IS FORECAST TO 
GRADUALLY WEAKEN DURING THE NEXT 36-48 HOURS. 

...TROPICAL WAVES...

A TROPICAL WAVE IS ALONG 89W N OF 3N. ISOLATED TO SCATTERED 
MODERATE CONVECTION IS NOTED WITHIN 180 NM AHEAD OF THE AXIS 
FROM 4N TO 7N. 

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG AXIS 08N78W TO 09N88W THEN 
RESUMES AT 13N104W TO 08N125W TO 07N140W. CLUSTER OF MODERATE TO 
ISOLATED STRONG CONVECTION IS N OF 05N BETWEEN 78W AND 82W. NO 
SIGNIFICANT CONVECTION ELSEWHERE.

...DISCUSSION...

AN UPPER LEVEL TROUGH STRETCHES OVER ARIZONA AND NW MEXICO INTO 
THE PAC WATERS TO NEAR 22N120W. BEHIND THE TROUGH...AN UPPER 
ANTICYCLONE CENTERED NEAR 18N135W HAS A RIDGE EXTENDING NE 
BEYOND 13N118W. A RIDGE ALSO EXTENDS SW TO OVER THE ITCZ WELL W 
OF AREA. OTHERWISE...THE UPPER LEVELS ARE VERY DRY N OF 15N AND 
W OF LINE FROM 24N107W TO 15N120W. UPPER NELY WINDS DOMINATES 
THE EPAC MAINLY E OF 110W WHERE ABUNDANT MID/UPPER LEVEL 
MOISTURE IS NOTED...INCLUDING CONVECTION ASSOCIATED WITH ALEX'S 
RAINBANDS AND THE PRESENCE OF A CLUSTER JUST S OF WESTERN PANAMA.

AT THE SURFACE...STRONG HIGH PRES LOCATED NW OF AREA EXTENDS A 
RIDGE SE OVER THE FORECAST WATERS COVERING ROUGHLY THE AREA N OF 
15N W OF 110W WITH THE EXCEPTION OF THE REMNANT LOW PRES OF 
CELIA WHICH REMAINS NEAR 16N124W. THE PRES GRADIENT BETWEEN THIS 
RIDGE AND THE REMNANT LOW OF CELIA IS PRODUCING N TO NE WINDS OF 
20 KT ESPECIALLY N OF 25N BETWEEN 122W AND 135W. THE AREA OF NLY 
WINDS ARE EXPECTED TO EXPAND OVER THE N WATERS N OF 20N AS THE 
HIGH PRES MOVES EWD. THE SAME HIGH PRES IS PRODUCING NW WINDS OF 
20 KT AND SEAS TO 8 FT WITHIN AROUND 120 NM OF THE SOUTHERN BAJA 
CALIFORNIA. THESE CONDITIONS ARE FORECAST TO PERSIST DURING AT 
LEAST THE NEXT 24 HOURS.  

ORGANIZED BANDS OF MODERATE CONVECTION...ASSOCIATED WITH THE 
OVERALL CIRCULATION OF HURRICANE ALEX LOCATED IN THE GULF OF 
MEXICO...ARE NOTED OVER THE PAC WATERS PARTICULARLY N OF 10N 
BETWEEN 90W AND 105W IN A SW WIND FLOW. UNDER THIS PATTERN... 
LOCALLY HEAVY RAIN MAY OCCUR ON THE LEEWARD SIDE OF THE SIERRA 
MADRE MOUNTAINS BETWEEN CHIAPAS AND JALISCO. 

THE REMNANT TROUGH OF FORMER TROPICAL CYCLONE DARBY EXTENDS 
18N104W TO 10N113W. SW WINDS OF 15 TO 20 KT CONTINUE WITHIN 
ABOUT 360 NM SE OF THE TROUGH. S SWELL...DRIVING SEAS TO 10 
FT...COVER THE REMAINDER OF THE AREA S OF 15N BETWEEN 80W AND 
115W. AS HURRICANE ALEX CONTINUES TO MOVE ACROSS THE WESTERN 
PORTION OF THE GULF OF MEXICO...THE DARBY REMNANT TROUGH WILL 
SHIFT NW ALONG THE COAST OF MEXICO WITH WINDS AND SEAS ENHANCED 
WITHIN ABOUT 300 NM SE OF THE TROUGH. IN THE MEANTIME...THE PAC 
WATERS AFFECTED BY THE CROSS EQUATORIAL SOUTHERLY SWELLS IS 
EXPECTED TO INCREASE TO COVER THE ENTIRE AREA W OF 79W AND TO 
THE SE OF A LINE FROM 17N104W TO 00N140W BY THU MORNING.

LARGE SWELLS FROM THE SOUTHERN HEMISPHERE WILL CONTINUE TO CROSS 
THE EQUATOR OVER THE SOUTH PORTION OF THE DISCUSSION AREA. A NEW 
BATCH OF S SWELLS SHOULD REACH THE EQUATOR BY THU BUILDING SEAS 
TO 12 FT S OF 03N BETWEEN 105W AND 124W BY FRI.  
 
LOOKING AHEAD...THE MARINE GUIDANCE SUGGESTS AN INCREASE IN 
WINDS AND SEAS ACROSS THE GULF OF CALIFORNIA FRI EVENING INTO 
SAT ASSOCIATED WITH A LOW PRES SITUATED OVER ARIZONA AND NW 
MEXICO. 

$$
GR