000
AXPZ20 KNHC 092206
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED FEB 09 2011

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...
THE AXIS OF THE ITCZ IS CENTERED FROM 08N84W TO 03N108W TO 
09N120W TO 07N130W TO 06N140W. NO SIGNIFICANT CONVECTION.

...DISCUSSION...
THE REX BLOCK PATTERN IN PLACE OVER THE PAST WEEK HAS FINALLY 
BROKEN DOWN AS THE RIDGE HAS SHIFTED TO THE WEST IN RESPONSE TO 
AN AMPLIFYING CYCLONE WELL NW OF THE AREA NEAR 45N150W. UPPER 
LEVEL TROUGHING DIGGING DOWN THE E SIDE OF THE RIDGE IS IN THE PROCESS
OF CAPTURING THE WELL DEFINED CYCLONIC VORTEX CENTERED NEAR 
25N132W AND ATTEMPTS TO SLOWLY EJECT IT SLOWLY EWD NEXT FEW 
DAYS. THIS APPEARS TEMPORARY AS MODEL GUIDANCE SUGGESTS A NEW 
UPPER LOW FORMS AT EDGE OF BASIN NEAR 18N138W KEEPING TROUGH IN 
PLACE IN NW CORNER OF E PAC WITH ANOTHER BLOCKING RIDGE OFF THE 
CALIFORNIA COAST. 

AXIS OF SUBTROPICAL JET E OF THE VORTEX/TROUGH IS ADVECTING
ABUNDANT MOISTURE INTO SOUTHERN BAJA CALIFORNIA PENINSULA AND NW 
MEXICO WITH CORE SPEEDS OF 85-100 KT. EMBEDDED WEAK SHORTWAVE 
TROUGH RACING EWD ALONG 111W IS FURTHER S THAN 00Z GUIDANCE 
SOLUTION AND SHOULD BRING FRESH NW WINDS ON BOTH SIDES OF 
PENINSULA FURTHER SOUTH THAN EARLIER FORECAST. 

AT THE SURFACE...
HIGH PRES 1037 MB NEAR 46N130W IS DRIFTING EAST 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 16 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 NW WINDS OF 20-25 KT 
FUNNELING INTO THE GULF BUT DIMINISH THU AS BOTH...HIGH PRES AND 
SHORTWAVE ALOFT...MOVE FURTHER E. 

$$
COBB