000
AXPZ20 KNHC 262224
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC TUE DEC 26 2006

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2115 UTC.

...ITCZ...
AXIS 6N77W 5N97W 5N117W 5N140W. SCATTERED MODERATE WITHIN 90 NM OF 
AXIS BETWEEN 77W AND 86W. ISOLATED MODERATE CONVECTION FROM 6N TO 9N 
BETWEEN 112W AND 118W WEAKENING. 

...DISCUSSION...
UPPER TROUGH...THE TRAILING END OF AN UPPER LOW MOVING INTO THE 
OREGON COAST...IS STALLING ALONG 138W MAINLY N OF 20N. BLOCKING 
UPPER RIDGE TO THE E OF THIS ALONG 120W. FURTHER E...UPPER TROUGH 
OVER THE CENTRAL GULF OF MEXICO EXTENDS SW ACROSS SRN 
MEXICO...BRINGING DRY AND STABLE AIRMASS OVER COASTAL MEXICO. BROAD 
1027 MB SURFACE HIGH PRES IS CENTERED NEAR 25N132W...AHEAD OF WEAK 
COLD FRONT ASSOCIATED WITH UPPER TROUGH TO THE NW. QUIKSCAT AND SHIP 
OBSERVATIONS ARE SHOWING PERSISTENT FRESH TO STRONG TRADES S OF THE 
RIDGE AXIS GENERALLY BETWEEN 5N AND 20N W OF 110W. LIGHT 
ANTICYCLONIC FLOW IS EVIDENT ALONG THE SURFACE RIDGE AXIS AT 25N. 
MEANWHILE...MORNING QUIKSCAT SHOWED STRONG GALE CONDITIONS 
CONTINUING OVER GULF OF TEHUANTEPEC IN RESPONSE TO 1029 MB HIGH OVER 
S TEXAS. UPPER RIDGE CENTERED NEAR 10N115W IS ENHANCING CONVECTION 
OVER THE ITCZ AS NOTED ABOVE. TIGHT GRADIENT ON THE EASTERN SIDE OF 
THE HIGH PRES IS PROMOTING FRESH NLY WINDS ALONG SRN GULF OF 
CALIFORNIA...ALTHOUGH THIS WILL DIMINISH TONIGHT AS HIGH PRES 
WEAKENS AND GRADIENT RELAXES.

LOOKING AHEAD...UPPER TROUGH ALONG 138W WILL LIFT OUT WITH 
ASSOCIATED SURFACE FRONT RETREATING NWD. RIDGE AXIS OVER 120W WILL 
ERODE IN RESPONSE TO THE TROUGH LIFTING TO THE N. HOWEVER...RIDGE 
WILL BUILD ALONG 135W AHEAD OF DEEPENING TROUGH IN THE CENTRAL 
PACIFIC...MAINTAINING SURFACE HIGH PRES W OF 118W. THIS WILL KEEP 
FRESH TO STRONG TRADE WIND FLOW S OF THE RIDGE OVER THE NEXT COUPLE 
OF DAYS. GALES OVER TEHUANTEPEC WILL DIMINISH OVER THE NEXT 24 HOURS 
AS RIDGE OVER THE GULF OF MEXICO WEAKENS AND SHIFTS E...AND RETURN 
FLOW BECOMES ESTABLISHED OVER THE WESTERN GULF OF MEXICO. SURGE OVER 
THE CARIBBEAN WILL BRING FRESH ELY FLOW INTO THE GULF OF 
PAPAGAYO...EXTENDING ALONG GENERALLY ALONG 10N TO 100W.

$$
CHRISTENSEN