000
AXPZ20 KNHC 250918
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC WED JUL 25 2007

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.

...SPECIAL FEATURE...

TROPICAL STORM DALILA CENTERED NEAR 19.0N 111.0W...NEAR SOCORRO 
ISLAND...AT 25/0900 UTC MOVING NW AT 6 KT.  MAXIMUM SUSTAINED 
WIND SPEED IS 50 KT WITH GUSTS TO 60 KT.  ESTIMATED MINIMUM 
CENTRAL PRESSURE IS 997 MB. IR SATELLITE ENHANCEMENT REVEALED 
THAT THE LOW-LEVEL CENTER IS ABOUT 90 NM N OF THE DEEPEST 
CONVECTION. THERE IS STILL JUST ENOUGH NORTHEASTERLY SHEAR TO 
KEEP THE MOST SIGNIFICANT CONVECTIVE BANDING OVER THE SRN 
SEMICIRCLE AND OTHER SCATTERED SHOWERS/TSTMS FARTHER N AND NEAR 
THE MEXICAN COAST. SCATTERED MODERATE TO STRONG CONVECTION IS 
WITHIN 240 NM OF THE CENTER OVER THE SOUTH QUADRANT. SEE LATEST 
NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 
KNHC FOR MORE DETAILS.

...TROPICAL WAVES...

TROPICAL WAVE EXTENDS S OF WESTERNMOST COSTA RICA ALONG 85W N OF 
4N MOVING W 15-20 KT. THE WAVE IS MOST PROMINENT OVER THE WRN 
CARIBBEAN WITH NO SIGNIFICANT CIRCULATION NOTED OVER THE PACIFIC 
WATERS.  

TROPICAL WAVE EXTENDS S OF MEXICO ALONG 98W N OF 5N MOVING W 15 
KT. THE DEEP CONVECTION OVER THE PACIFIC WATERS EARLIER IN THE 
DAY HAS MOSTLY DISSIPATED.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG THE LINE...5N77W 5N90W 10N105W THEN 
12N115W 12N130W 9N140W. THERE IS NO SIGNIFICANT CONVECTION.

...DISCUSSION...

E OF 110W...
A STAGNANT UPPER LEVEL PATTERN PERSISTS ACROSS THE CENTRAL PART 
OF THE AMERICAS WITH AN UPPER HIGH CENTERED JUST E OF COZUMEL 
MEXICO AND A SHARP UPPER TROUGH STILL POSITIONED ACROSS THE NW 
GULF INTO CENTRAL MEXICO. A SRN EXTENSION OF THE TROUGH ALSO 
STRETCHES FROM NEAR VERACRUZ MEXICO SWD 12N98W OVER THE PACIFIC. 
E OF THE TROUGH...FAIRLY STRONG E/NE FLOW IS BEING DRIVEN BY THE 
UPPER HIGH OVER THE W CARIBBEAN RESULTING IN SHEAR THAT IS TOO 
HIGH FOR ANY TROPICAL DEVELOPMENT. W OF THE TROUGH...T.S. DALILA 
IS PRODUCING ITS OWN UPPER LEVEL ANTICYCLONE WITH AN AXIS ALONG 
16N.

TSTMS OVER THE SIERRA MADRE OCCIDENTALS OF MEXICO HAVE 
DIMINISHED AS THE NIGHTTIME COOLING OF THE SURFACE TAKES PLACE.  
SOME OF THE ACTIVITY OFF THE COAST IS  IN ASSOCIATION WITH THE 
OUTER BANDS OF T.S. DALILA.  

W OF 110W...
A LARGE UPPER HIGH IS CENTERED W OF BAJA CALIFORNIA NEAR 27N124W 
WITH A RIDGE AXIS EXTENDING SW TO 13N140W. WIDESPREAD DRY AIR 
AND LARGE-SCALE SUBSIDENCE LIE GENERALLY N OF 18N W OF 115W. S 
OF THE RIDGE...BROAD NE/E FLOW EXTENDS FROM T.S. DALILA AND THE 
SURROUNDING WATERS ALL THE WAY TO 140W. AS A RESULT...THE ITCZ W 
OF DALILA IS QUITE LINEAR AT THE MOMENT WITH VERY FEW ORGANIZED 
CONVECTIVE CLUSTERS.
 
$$
LL