000
AXPZ20 KNHC 122224
TWDEP 

TROPICAL WEATHER DISCUSSION NWS 
TPC/NATIONAL HURRICANE CENTER 
2205 UTC TUE SEP 12 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 
2145 UTC.

...TROPICAL WAVES...
TROPICAL WAVE N OF 6N ALONG 101W MOVING W 10 KT.  STRONG 
DIFFLUENT FLOW ALOFT ENHANCING BURST OF MODERATE TO STRONG 
CONVECTION WITHIN 120 NM OF AXIS.  MECHANICAL UPLIFT AND DAYTIME 
HEATING HAS ALSO PROMPTED SCATTERED MODERATE CONVECTION WITHIN 
150 NM W OF AXIS N OF 14N...INCLUDING GULF OF TEHUANTEPEC. 

...ITCZ...
ITCZ AXIS CENTERED ALONG 8N78W  8N85W  13N97W  8N128W  10N140W.  
SCATTERED MODERATE CONVECTION...STRONGER NEAR COAST...N OF 4N
E OF 91W.  SCATTERED MODERATE TO STRONG CONVECTION WITHIN 180 NM 
OF AXIS W OF 93W.

...DISCUSSION...
MID/UPPER LEVEL TROUGH AT THE EDGE OF NW CORNER OF FORECAST AREA 
FINDING STRONG RESISTANCE IN HEALTHY BROAD WELL ANCHORED 
ANTICYCLONE AT 23N130W BLOCKING FURTHER EWD ENCROACHMENT.  
CYCLONIC VORTEX PULLING TROUGH HAS LITTLE CHOICE BUT TO HEAD NE 
STALLING TROUGH AND EVENTUALLY DISSIPATING IT.  

ANTICYCLONE HAS UPPER LEVEL RIDGE EXTEND TO SECOND ANTICYCLONE 
AT 24N104W THEN FURTHER E INTO GULF OF MEXICO.  CYCLONIC VORTEX 
OVER ARIZONA HAS WEAK TROUGH ALONG 114W AND GULF OF CALIFORNIA 
LITERALLY SPLITTING ANTICYCLONES AND BRINGING PATCH OF DRY AIR 
MASS TO AN OTHERWISE VERY MOIST E PAC.

SRN PERIPHERY OF RIDGE HAS PLENTY OF CONVECTIVE ACTIVITY DUE TO 
ABUNDANT MOISTURE...GOOD DIFFLUENT FLOW ALOFT AND HEALTHY UPLIFT
IN TROPICAL WAVE AND LOW PRES CENTERS MENTIONED BELOW.   

LOW PRES 1009 MB...REMNANTS OF KRISTY...AT 10N137W DRIFT W. 
SECOND 1009 MB LOW PRES AT 11N117W MOVING W 10 KT ENHANCING 
ITCZ CONVECTION DUE TO WELL DEFINED UPPER LEVEL DIFFLUENT FLOW. 
ANOTHER LOW PRES...1008 MB...AT 13N97W FORECASTED BY GFDL TO HUG 
MEXICAN COAST ON A NW TRACK AND INTENSIFY AS UPPER CONDITIONS 
BECOMING MORE FAVORABLE WITH WLY DRIFT. 

STRONG CROSS EQUATORIAL LOW LEVEL FLOW S OF 10N W OF 95W.  
SURFACE RIDGE WELL NW OF AREA PRODUCING NE WINDS THROUGH NEXT
48 HOURS FROM 12N-24N W OF 133W...WITH SOME HELP FROM THE 
REMNANTS OF KRISTY.  

$$
WALLY BARNES