000
AXPZ20 KNHC 251549
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED JUL 25 2007

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 
1500 UTC.

...SPECIAL FEATURE...
TROPICAL STORM DALILA AT 19.7N 111.9W AT 25/0900 UTC MOVING NW 
AT 6 KT.  MAXIMUM SUSTAINED WIND SPEED 45 GUSTS TO 55 KT.  
ESTIMATED MINIMUM CENTRAL PRESSURE IS 1000 MB.  CONTINUOUS NE 
SHEAR HAS CURTAILED ANY SIGNIFICANT DEVELOPMENT OF SYSTEM WHICH 
APPEARS TO HAVE PEAKED SINCE IT NOW ENTERS ADVERSE UPPER AND 
SURFACE ENVIRONS.  COOL SSTS...STABLE AIR MASS AND INCREASING NE 
SHEAR SHOULD DRAIN DALILA ENERGY.  FORECAST TO BECOME A 
TROPICAL DEPRESSION WITHIN NEXT 48 HRS.  SCATTERED MODERATE 
ISOLATED STRONG CONVECTION REMAINING CONFINED TO 300 NM S 
QUADRANT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO 
HEADERS MIATCMEP2/WTPZ22 KNHC FOR MORE DETAILS.

...TROPICAL WAVES...
TROPICAL WAVE ALONG 88W N OF 4N MOVING W 15 KT.  ISOLATED 
MODERATE CONVECTION WITHIN 60 NM OF WAVE AXIS FROM 5N-8N.
NO ORGANIZATION OR SIGNS OF DEVELOPMENT ASSOCIATED WITH WAVE.  

TROPICAL WAVE EXTENDS ALONG 98W N OF 5N MOVING W 15 KT.  
SCATTERED CONVECTION WITHIN 30 NM OF AXIS N OF 8N.  NO 
ORGANIZATION OR SIGNS OF DEVELOPMENT ASSOCIATED WITH WAVE.  

...ITCZ...
ITCZ AXIS ALONG...7N78W 9N102W 15N109W 10N140W.  SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WITHIN 90 NM OF AXIS FROM 
94W TO 102W.

...DISCUSSION...
UPPER LEVEL TROUGH OFF NW CORNER OF E PAC HAS BEEN UNABLE TO 
ENCROACH INTO BASIN DUE TO STRENGTH OF WELL ANCHORED MID-UPPER 
LEVEL ANTICYCLONE CENTERED AT 28N123W.  RIDGE EXTEND SW TO ITCZ 
CURTAILING ANY DEVELOPMENT W OF 130W AND MAINTAINING VERY DRY 
AIR MASS N OF 17N W OF 120W.  SECOND UPPER LEVEL ANTICYCLONE 
OVER YUCATAN PASSAGE MAINTAINS STEADY FLOW OF MOISTURE INTO E 
PAC ACROSS HONDURAS AND GUATEMALA FEEDING INTO ITCZ...BUT 
HOSTILE UPPER LEVEL ENVIRON SUPPORTS LITTLE CONVECTION ALONG 
TROPICAL WAVES MENTIONED ABOVE.  SOME ACTIVITY OVER BAY OF 
CAMPECHE NOTED UNDER DIFFLUENT PATTERN ALOFT. 

AT THE SURFACE...LITTLE SIGNIFICANT FEATURES IN E PAC EXCEPT 
T.S. DALILA DISCUSSED ABOVE. 
 
$$
WALLY BARNES