000
AXPZ20 KNHC 231554
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC MON JUL 23 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 
1545 UTC.

...SPECIAL FEATURE...

TROPICAL STORM DALILA CENTERED NEAR 14.8N 108.9W...OR ABOUT 
420 MILES...675 KM...SOUTHWEST OF MANZANILLO MEXICO AND
565 MILES...905 KM SOUTH OF THE SOUTHERN TIP OF BAJA CALIFORNIA. 
AT 23/1500 UTC MOVING NW AT 9 KT. MAXIMUM SUSTAINED WIND SPEED 
IS 35 KT WITH GUSTS TO 45 KT. ESTIMATED MINIMUM CENTRAL PRESSURE 
IS 1005 MB. FIRST VISIBLE IMAGES SHOW AN EXPOSED LOW LEVEL 
CENTER TO THE NORTHEAST OF A BAND OF SCATTERED STRONG CONVECTION 
WHICH EXTENDS OUT TO 210-240 NM IN THE SOUTHWEST QUADRANT OF THE 
SYSTEM. NORTHEASTERLY SHEAR OF 30 KT HAS KEPT THE DEEP 
CONVECTION DISPLACED TO THE SOUTHWEST OF THE LOW LEVEL CENTER 
FOR SEVERAL DAYS WITH THE END RESULT BEING A VERY SLOW 
INTENSIFICATION OF THE STORM. ADDITIONAL SCATTERED MODERATE TO 
STRONG CONVECTION WAS NOTED WITHIN 60-75 NM OF BAND ALONG 
17N107W 15N103W 13N102W WELL REMOVED FROM THE LOW LEVEL CENTER. 
SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS 
MIATCMEP2/WTPZ22 KNHC FOR MORE DETAILS. 

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 8N78W 10N92W 16N104W 14N120W 10N130W 
8N140W. SCATTERED MODERATE ISOLATED STRONG WITHIN 90 NM OF THE 
AXIS BETWEEN 95W AND 102W. SCATTERED MODERATE ISOLATED STRONG 
WITHIN 60-75 NM OF THE AXIS BETWEEN 115W AND 119W...AND W OF 
124W. SCATTERED MODERATE WITHIN 90 NM OF THE COAST OF CENTRAL 
AMERICA BETWEEN 84W AND 89W.

...DISCUSSION...

E OF 110W...
AN EXTENSION OF A DEEP MID TO UPPER LEVEL TROUGH OVER THE ERN 
CONUS EXTENDS WELL SOUTH INTO AN UPPER LOW CENTERED OVER THE BAY 
OF CAMPECHE NEAR 22N95W. A STRONG UPPER HIGH IS OVER THE SEA OF 
CORTEZ/CENTRAL BAJA CALIFORNIA. STEADY BUT DIFLUENT NORTHERLY 
FLOW EXISTS BETWEEN THE TWO FEATURES ACROSS MUCH OF MEXICO AND 
EXTENDING S AND TURNING W OVER THE PACIFIC WATERS. THIS STRONG 
FLOW IS PRODUCING 30-35 KT OF NORTHEASTERLY SHEAR OVER T.S 
DALILA AND ALLOWING ONLY FOR SLOW INTENSIFICATION AT THIS TIME.  
AN INVERTED UPPER TROUGH LIES S OF THE GULF OF TEHUANTEPEC ALONG 
98W WITH A COL REGION NOTED JUST W OF THE GULF OF TEHUANTEPEC. 
SOMEWHAT DIFLUENT FLOW SE OF THE INVERTED TROUGH IS RESULTING 
IN THUNDERSTORM ACTIVITY FROM GULF OF TEHUANTEPEC EASTWARD TO 
THE COAST OF GUATEMALA. UPPER LEVEL ANTICYCLONE W OF JAMAICA IS 
PRODUCING BROAD AND DEEP EASTERLY FLOW OUT OF COLOMBIA INTO THE 
E PACIFIC BASIN...AND THE HIGH MOISTURE VALUES ARE ALLOWING 
SCATTERED TSTMS TO DEVELOP ALONG THE ITCZ AS WELL AS INLAND FROM 
PANAMA TO NICARAGUA.

W OF 110W...
THE PREVAILING UPPER LEVEL FEATURE OVER THE W PART OF THE AREA 
IS A NE-SW ORIENTED UPPER HIGH LOCATED OVER THE SEA OF CORTEZ 
NEAR 29N113W WITH ANOTHER CENTER NEAR 24N121W WITH THE 
CIRCULATION DOMINATING MOST OF THE AREA W OF 110W. THE HIGH IS 
ADVECTING DEEP TROPICAL MOISTURE FROM THE E PART OF THE BASIN 
WWD TO ABOUT 130W WHERE IT THINS OUT CONSIDERABLY IN THE FACE OF 
LARGE-SCALE SUBSIDENCE TO THE NW. A SHEARING MID/UPPER TROUGH IS 
LOCATED JUST NW OF 30N140W JUST W OF THE UPPER HIGH/RIDGE SYSTEM 
WITH THE ASSOCIATED SURFACE FRONT JUST TO THE NW OF THE AREA. 
AS A RESULT OF THE PRESENCE OF THE FRONT THE SUBTROPICAL RIDGE 
IS WEAKER THAN NORMAL WITH SUBNORMAL EASTERLY TRADES MAINLY W OF 
130W. OVERALL PATTERN IS NOT EXPECTED TO CHANGE OVER THE NEXT 
FEW DAYS.
 
$$
COBB