000
AXPZ20 KNHC 211638
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT NOV 21 2009

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 
1445 UTC.

...ITCZ...
AXIS EXTENDS FROM 06N77W TO 05N112W TO 08N123W TO 07N140W.  
SCATTERED MODERATE TO STRONG CONVECTION WITHIN 150 NM N AND 90 
NM S OF AXIS W OF 122W.  SCATTERED MODERATE CONVECTION WITHIN 90 
NM S OF AXIS E OF 81W.

...DISCUSSION...
VERY BROAD MID-UPPER LEVEL RIDGE CENTERED AT 09N118W ALMOST 
COVER THE ENTIRETY OF BASIN WITH MOST OF AIR MASS E OF 120W 
BEING VERY DRY.  DEEP LAYER TROUGH MOVING INTO NW CORNER OF E 
PAC DOES NOT REACH MUCH FURTHER S AS RIDGE BLOCK PREVENTS IT.  
SECOND UPPER LEVEL TROUGH S OF GULF OF TEHUANTEPEC REACHES 
00N106W AMID DRY AIR MASS.  

AT THE SURFACE...
HIGH PRES 1028 MB CENTERED AT 38N142W HAS RIDGE EXTEND SE TO 
15N105W MAINTAINING FRESH TO STRONG TRADES W OF 120W.  LARGE 
LONG PERIOD NW SWELL SPREAD SE COVERING MOST OF E PAC EXCEPT 
ALONG TRADE BELT AND S OF 10N WHERE CROSS EQUATORIAL SWELL 
INVADE N OF THE EQUATOR.

GAP WINDS CONTINUE THEIR MODERATE BREEZE IN GULF OF PAPAGAYO.
WEAK COLD FRONT CROSSING GULF OF MEXICO PICK UP AGAIN WITHIN 18 
HRS BUT QUICKLY DIMINISH MON.   

$$
WALLY BARNES