000
AXPZ20 KNHC 180343
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON AUG 18 2008

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0315 UTC.

...TROPICAL WAVES...
NONE.

...ITCZ...
ITCZ ALONG 09N84W TO 11N108W TO 10N118W TO 11N130W TO 09N140W. 
SCATTERED MODERATE CONVECTION WITHIN 120 NM N OF AXIS FROM 
89W-93W.  SCATTERED MODERATE CONVECTION WITHIN 90 NM S OF AXIS 
FROM 89W-96W AND 107W-111W.  SCATTERED MODERATE ISOLATED STRONG 
CONVECTION WITHIN 240 NM N OF AXIS FROM 112W-130W AND WITHIN 60 
NM S OF AXIS W OF 130.

...DISCUSSION...
UPPER LEVEL TROUGH ENTERS E PAC AT 32N131W TO 28N140W MOVING NE 
AS REBUILT MID-UPPER LEVEL BROAD RIDGE BLOCKS ANY FURTHER EWD 
INTRUSION.  LARGE DRY AIR MASS SWATH AS MUCH AS 10 DEG WIDE 
AHEAD OF TROUGH AXIS MAINTAINS CONVECTION-FREE REGION N OF 16N W 
OF 120W.  BROAD RIDGE MAINTAINS MOIST ANTICYCLONIC FLOW E OF 
120W BUT WITH MODERATE TO STRONG ELY WIND SHEAR OVER ITS 
DOMAIN.  NO SURFACE SYSTEMS TO ACTIVATE DEEP CONVECTION N OF 
ITCZ EXCEPT LOW PRES REMNANTS OF ISELLE NOW NEAR 19N115W.

AT THE SURFACE...
ITCZ FAIRLY MOIST BUT LACK UPLIFTING MECHANISMS FOR DEEPER 
CONVECTION.  HIGH PRES COVERS MOST OF REGION N OF ITCZ BUT WEAK 
STATIONARY FRONT SUPPORTED BY ABOVE-MENTIONED UPPER LEVEL TROUGH 
DENTS NW CORNER OF E PAC FROM 32N137W TO 29N140W.  FRONT TO 
DISSIPATE WITHIN NEXT 24 HRS WITH SIGNIFICANT IMPACT ON WIND OR 
SEAS IN FORECAST WATERS. 

$$
WALLY BARNES