000
AXPZ20 KNHC 131002
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON SEP 13 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...ITCZ...
AXIS FROM 11N86W TO 11N114W TO 101N127W TO 12N132W TO 12N140W. 
SCATTERED MODERATE CONVECTION WITHIN 120 NM S OF AXIS E OF 95W.  
SCATTERED MODERATE TO STRONG CONVECTION WITHIN 90 NM OF AXIS 
FROM 120W TO 134W.

...DISCUSSION...
LARGE UPPER LEVEL ANTICYCLONE CENTERED OVER E TEXAS EXTENDS  
RIDGE SOUTHWEST TO 22N110W BEING FORCED E BY SHARP DEEP 
AMPLITUDE TROUGH MOVING NE FROM 32N115W TO CUTOFF CYCLONE AT 
19N125W.  CONVERGING WIND FLOW PROMPTING MODERATE TO STRONG 
SUBSIDENCE N OF 14N W OF 112W. SECOND LARGE UPSTREAM ANTICYCLONE 
AT 25N126W EXTEND DRY AND STABLE SUBSIDING AIR MASS W TO 140W N 
OF ITCZ.  

TEXAS ANTICYCLONE PROVIDE ITCZ WITH STEADY FLOW OF STRONG 
EASTERLIES WHICH PRESENT ADVERSE ENVIRONMENT ALOFT FOR SUSTAINED 
DEEP CONVECTION ALTHOUGH ABUNDANT TROPICAL MOISTURE IS ADVECTED 
ALONG ITCZ ALL THE WAY TO 135W.  MODERATE DIFFLUENT FLOW AT BASE 
OF UPPER LEVEL CYCLONE ENHANCES CONVECTION ALONG ITCZ AS 
MENTIONED IN PARAGRAPH BELOW.  

AT THE SURFACE...
STRING OF EMBEDDED LOW PRES CENTERS DOT ITCZ MAINLY W OF 112W.
CENTERS W OF 110W COMING UNDER UPPER DIFFLUENCE ABLE TO ENHANCE 
DEEP CONVECTION AND FRESH TO STRONG BREEZE.  

WEAK TROUGH APPROACHING ISTHMUS OF TEHAUNTEPEC EXPECTED FUNNEL N 
WIND FLOW ACROSS INTO ITS SOUTHERN WATERS INCREASING TO STRONG 
BREEZE.

HIGH PRES CENTER 1024 MB MOVES E PRESSING GRADIENT AGAINST LOW 
PRES TROUGH ALONG CALIFORNIA RESULTING IN STRONG N WINDS ALONG 
COAST WHICH EXTEND S OF 28N. 

$$
WALLY BARNES