000
AXPZ20 KNHC 091551
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED FEB 09 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 08N82W TO 03N94W TO 09N117W TO 07N129W TO 04N140W. 
SCATTERED MODERATE CONVECTION WITHIN 60 NM N OF AXIS FROM 125W 
TO 129W.

...DISCUSSION...
BREAKDOWN OF REX BLOCK PATTERN SHIFTED UPPER LEVEL RIDGE AXIS 
ALONG 95W KEEPING VERY DRY AIR MASS S OF 20W E OF 110W DUE TO 
MODERATE TO STRONG SUBSIDENCE.  WELL DEFINED CYCLONIC VORTEX AT 
25N132W DIGS SE ADVECTING ABUNDANT MOISTURE INTO SOUTHERN TIP 
OF BAJA CALIFORNIA PENINSULA AND NW MEXICO RIDING IN 75-80 KT 
JET CORE.  WEAK SHORTWAVE TROUGH RACING ALONG 113W IS FURTHER S 
THAN 00Z GUIDANCE SOLUTION AND SHOULD BRING STRONG NW BREEZE ON 
BOTH SIDES OF PENINSULA DOWN TO LOWER LATITUDES THAN ANTICIPATED.
MODEL GUIDANCE OPENS VORTEX INTO SHARP NE-SW TROUGH THU BUT NEW 
CYCLONE FORMS AT EDGE OF BASIN NEAR 19N140W KEEPING TROUGH IN 
PLACE IN NW CORNER OF E PAC WITH BLOCKING STATIONARY RIDGE E OF 
120W.  THIS PATTERN HOLDS THROUGH END OF FORECAST PERIOD. 

AT THE SURFACE...
HEALTHY HIGH PRES 1040 MB AT 46N130W DRIFT E TODAY AND TIGHTENS 
GRADIENT AGAINST TROUGH EXTENDING FROM CENTRAL CALIFORNIA TO 
27N117W INCREASING STRONG N WINDS.  WINDS REACH GALE FORCE JUST  
N OF 30N E OF 130W WITH ASSOCIATED SWELLS AS HIGH AS 18 FT 
ENCROACHING INTO E PAC N OF 20N.  GALE WINDS ARE SHORT LIVED AS 
ABOVE MENTIONED SHORT WAVE SPEEDS NE OUT OF REGION LATER TODAY 
AND RIDGE EDGES E.  AREA OF FRESH NE TRADE WIND OVER W WATERS 
SHRINK THU AS HIGH PRES MOVES.

GAP WINDS...
COLD FRONT ASSOCIATED WITH AFOREMENTIONED UPPER TROUGH DIPPING 
ACROSS NW MEXICO SEND ANOTHER BATCH OF DENSE...COLD AND DRY AIR 
INTO WESTERN GULF OF MEXICO AND THROUGH ISTHMUS OF TEHUANTEPEC 
EARLY THU.  N-NE WINDS INCREASE TO GALE FORCE LATE THU. 

GULF OF PAPAGAYO...STRONG SOUTHWESTERN CARIBBEAN NE TRADES SPILL 
ACROSS COSTA RICA MOUNTAINS WITH FRESH BREEZE IN GULF OF 
PAPAGAYO.  WINDS QUICKLY DIMINISH BELOW 20 KT TODAY ALTHOUGH ARE 
LIKELY TO INCREASE AGAIN LATE IN PERIOD AS COLD FRONT CROSSES 
WESTERN CARIBBEAN.

GULF OF CALIFORNIA...SHORTWAVE SUPPORT ALOFT AND TIGHT GRADIENT 
BETWEEN HIGH PRES TO THE NW AND WEAK SURFACE TROUGH JUST 
OFFSHORE ALONG BAJA PENINSULA BRING FRESH TO STRONG NW BREEZE 
FUNNELING INTO GULF EARLY TODAY BUT DIMINISH THU AS BOTH...HIGH 
PRES AND SHORTWAVE ALOFT...MOVE FURTHER E. 

$$
WALLY BARNES