000
AXPZ20 KNHC 071554
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC MON MAR 07 2011

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.

...ITCZ...
AXIS FROM 02N78W TO 01N98W TO 04N86W TO 02N99W TO 05N105W TO 
05N130W TO 03N140W.  ISOLATED MODERATE CONVECTION WITHIN 60 NM S 
OF AXIS FROM 88W TO 99W AND WITHIN 180 NM OF AXIS FROM 101 TO 
123W.  WEAK TROUGH EMBEDDED IN ITCZ 04N-08W ALONG 129W HAS 
SCATTERED MODERATE CONVECTION WITHIN 180 NM W OF TROUGH AXIS.

...DISCUSSION...
LARGE FLATTENED UPPER LEVEL RIDGE COVER MOST OF E PAC E OF 120W 
WITH DRY AND STABLE SUBSIDING AIR MASS THAT CURTAILS CONVECTION 
EXCEPT SOME ISOLATED DEBRIS LEFT OVER FROM PRIOR TSTMS.  

SHARP POSITIVELY TILTED UPPER TROUGH EXTEND FROM NORTHERN BAJA 
CALIFORNIA TO 05N137W FOLLOWED UPSTREAM BY SMALL AND WEAK RIDGE 
CREST ALONG 140W.  W SIDE OF RIDGE ADVECTS ABUNDANT MOISTURE 
INTO NW CORNER OF BASIN ON 60 KT JET CORE.  GUIDANCE HAS TROUGH 
RIDING QUICKLY OVER FLATTENED RIDGE CREST AND REPLACED BY SECOND 
DEEPER TROUGH OVER NW CORNER OF REGION.  SECOND TROUGH USHERS 
COLD FRONT INTO BASIN BUT STUBBORNLY ANCHORED FLAT RIDGE REFUSES 
TO BUDGE AND WILL STEER SECOND TROUGH NE OUT OF AREA. 

AT THE SURFACE...WEAK DISSIPATING COLD FRONT FROM 32N117W TO 
27N119W SUPPORTED BY ABOVE MENTIONED POSITIVELY TILTED UPPER 
TROUGH MOVES INLAND WITHIN NEXT 12 HR.  FRESH N WINDS WITH SEAS 
TO 8 FT ASSOCIATED WITH FRONT LINGER ADDITIONAL 24 HR LATER.
GALE CONDITIONS N OF 30N ALONG CALIFORNIA COAST AS HIGH PRES 
1030 MB BEHIND DISSIPATING COLD FRONT APPROACHES MAINLAND TUE.  
GRADIENT EASES AND ALLOW WINDS TO DROP BELOW ADVISORY CRITERIA 
BUT NW SWELL TO 9 FT LINGER E OF 123W N OF 22N.

GAP WINDS...
GULF OF CALIFORNIA...COLD FRONT MOVE THROUGH NORTHERN GULF OF 
CALIFORNIA TUE AND NORTHERLY WINDS EXPECTED TO INCREASE TO 20 KT.

GULF OF TEHUANTEPEC...FRESH N WINDS QUICKLY DIMINISH BELOW 20 KT 
TONIGHT AS FRONT AND HIGH PRES BEHIND OVER GULF OF MEXICO MOVE E 
AWAY FROM AREA.

GULF OF PAPAGAYO...WINDS EXPECTED TO PULSE DURING MORNING HRS 
TODAY AND TUE AS PRES GRADIENT INCREASES BEHIND AFOREMENTIONED 
COLD FRONT ENTERING NORTHWESTERN CARIBBEAN.

GULF OF PANAMA...FRESH N WINDS EXPECTED TO BECOME A MODERATE 
BREEZE THIS AFTERNOON.

$$
WALLY BARNES