000
AXPZ20 KNHC 061015
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC WED AUG 06 2008

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 
0915 UTC.

...SPECIAL FEATURE...
LOW PRES 1007 MB AT 12N109W IS EMBEDDED IN TROPICAL WAVE MOVING 
W AT 10 KT.  SYSTEM ABLE TO MAINTAIN DEEP CONVECTION GOING EVEN 
AGAINST ADVERSE UPPER ENVIRONMENT AND MODERATE ELY WIND SHEAR.  
MORE FAVORABLE CONDITIONS FOR DEVELOPMENT AHEAD WITH MODEL 
GUIDANCE SUGGESTING MODERATE DIFFLUENT FLOW ALOFT AND DECREASED 
SHEAR.  SYSTEM UNDER MONITORING AS SIGNS OF CYCLONIC TURNING ARE 
EXPECTED WITHIN NEXT 24-36 HRS.  BURST OF DEEP CONVECTION IN NW 
QUADRANT WITHIN LAST 4 HR MIGHT BE PRECURSOR OF INTENSIFICATION.

...TROPICAL WAVES... 
TROPICAL WAVE N OF 5N ALONG 93W MOVING W 15 KT.  LITTLE OR NO 
CYCLONIC ORGANIZATION ASSOCIATED WITH WAVE AND ENVIRONMENT ALOFT 
NOT FAVORABLE FOR DEVELOPMENT AS CYCLONIC VORTEX FORCES DRY AIR 
MASS ON NW QUADRANT OF AXIS.  BURST OF CONVECTION OVER GULF OF 
TEHUANTEPEC EXPECTED TO BE SHORT LIVED.

TROPICAL WAVE ALONG 127W FROM 3N-17N MOVING W 15 KT.  ADVERSE 
UPPER ENVIRONMENT APPEARS TO HAVE ARRESTED DEVELOPMENT OF SYSTEM 
DESPITE PLENTY OF AVAILABLE MOISTURE.  MORE FAVORABLE CONDITIONS 
ALOFT IN PATH OF WAVE SO INCREASE OF CONVECTION ALONG ITCZ IS 
EXPECTED.

...ITCZ...
ITCZ AXIS ALONG 09N84W TO 12N109W TO 09N119W 11N126W 09N132N TO 
10N140W.  SCATTERED MODERATE/ISOLATED STRONG CONVECTION WITHIN 
300 NM OF AXIS FROM 95W-100W AND 150 NM OF AXIS FROM 110W-115W.  
SCATTERED MODERATE CONVECTION WITHIN 120 NM OF AXIS W OF 130W. 

...DISCUSSION...
LARGE AMPLITUDE UPPER LEVEL TROUGH ENTERS E PAC 32N130W TO 
CYCLONIC VORTEX AT 18N133W COMBINE WITH BROAD RIDGE CENTERED 
22N113W TO CREATE LARGE AREA OF CONFLUENT FLOW ALOFT.  MODERATE 
TO STRONG SUBSIDENCE MAINTAINS DRY AIR MASS N OF 20N W OF 115W.
ABUNDANT TROPICAL MOISTURE FROM 05N-20N RUNS ALONG ITCZ AXIS 
WITH DEEP CONVECTION SPROUTING ALONG TROPICAL WAVES. 

ELSEWHERE AT THE SURFACE...HIGH PRES CENTER 1028 MB AT 36N146W 
HAS BROAD RIDGE EXTEND TO 17N116W CAPPING DRY STABLE AIR MASS 
WITH LOW STRATIFIED CLOUD OVER LARGE PART OF E PAC.  MODERATE 
TRADES FROM 10N-20N W OF 130W THROUGH FORECAST PERIOD.  
SCATTERED SHOWERS ALONG GULF OF CALIFORNIA E COAST TO 20N 
DECREASING IN COVERAGE AND INTENSITY LAST 3-4 HRS. 

GULF OF PAPAGAYO WINDS HAVE INCREASED WITH THE STRENGTHENING OF 
EQUATORIAL TROUGH RUNNING JUST ALONG 08N-09N E OF 90W.  WIND 
BARELY REACH 20 KT BUT EXPECTED TO LAST THROUGH FORECAST PERIOD. 
TROUGH ENHANCES SLY FLOW WITH LONG PERIOD LARGE BUT SUBSIDING S 
SWELLS IMPACTING S OF 10N.

$$
WALLY BARNES