000
AXPZ20 KNHC 240317
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE JUL 24 2007

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 
0300 UTC.

...SPECIAL FEATURE...

TROPICAL STORM DALILA CENTERED NEAR 16.1N 109.3W...OR ABOUT 185 
NM SSE OF SOCORRO ISLAND...AT 24/0300 UTC MOVING NNW AT 7 KT. 
MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. 
ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB. THE LARGE UPPER 
HIGH OVER THE BAJA PENINSULA AND UPPER TROUGH OVER THE GULF OF 
MEXICO CONTINUE TO PRODUCE 20 KT OF ENE SHEAR OVER DALILA YET 
THE SYSTEM IS STILL PRODUCING SIGNIFICANT CONVECTION ON ITS SW 
PERIPHERY. A LARGE BLOW-UP OF CONVECTION BEGAN JUST BEFORE 00 
UTC AND HAS BEEN MAINTAINED FOR THE PAST FEW HOURS EVEN WITH THE 
SHEAR SCALPING IT OFF TO THE SW. NUMEROUS STRONG CONVECTION IS 
WITHIN 180 NM SW QUADRANT...AND SCATTERED MODERATE IS ELSEWHERE 
FROM 12N-18N BETWEEN 110W-115W. SEE LATEST NHC FORECAST/ADVISORY 
UNDER AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC FOR MORE DETAILS.

...TROPICAL WAVES...

TROPICAL WAVE EXTENDING S OF GUATEMALA ALONG 90W N OF 5N MOVING 
W 15 KT. THE WAVE IS ASSOCIATED WITH A LARGE CLUSTER OF TSTMS 
OVER THE YUCATAN PENINSULA. EXCEPT FOR A BROAD CIRCULATION LYING 
ALONG THE ITCZ...THERE IS NO SIGNIFICANT REFLECTION OF THE WAVE 
OVER THE PACIFIC WATERS.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 8N77W 7N84W 15N105W THEN 14N110W 
12N124W 8N135W 8N140W. SCATTERED MODERATE/ISOLATED STRONG 
CONVECTION FROM 10N-15N BETWEEN 101W-107W. SCATTERED MODERATE 
WITHIN 60 NM OF AXIS BETWEEN 114W-123W. SCATTERED MODERATE 
WITHIN 60 NM OF AXIS W OF 135W.

...DISCUSSION...

MEXICO...
A DEEP UPPER LEVEL TROUGH OVER THE GULF OF MEXICO...WITH ITS 
AXIS STRETCHING W ACROSS MEXICO FROM NEAR MEXICO CITY TO THE 
GULF OF CALIFORNIA...CONTINUES TO PRODUCE STRONG NORTHERLY FLOW 
OVER MUCH OF THE COUNTRY. TSTMS DEVELOPED OVER THE SIERRA MADRE 
OCCIDENTALS...AND THIS FLOW PUSHED THE ACTIVITY TOWARDS THE 
PACIFIC COAST AND GULF OF CALIFORNIA AS HAS BEEN OCCURRING THE 
PAST FEW DAYS. CURRENTLY THE STRONGEST AND MOST WIDESPREAD 
ACTIVITY IS LOCATED OVER THE STATE OF SONORA EXTENDING N INTO 
ARIZONA.

E OF 110W...
THE SHARP AND DEEP MID TO UPPER LEVEL TROUGH EXTENDING SW ACROSS 
THE GULF OF MEXICO HAS SOMEWHAT BRIDGED THE ISTHMUS OF 
TEHUANTEPEC AND MERGED WITH AN INVERTED TROUGH LOCATED S OF 
MEXICO ALONG 100W. THE TROUGH IS EMBEDDED IN THE DEEP EASTERLIES 
AND IS MOVING W AT ABOUT 10 KT. AN UPPER RIDGE EXTENDING FROM A 
HIGH NEAR THE CAYMAN ISLANDS SW ACROSS GUATEMALA TO 12N98W IS 
PRODUCING WEAK DIFFLUENCE WHERE THE FLOW DIVERGES FROM THE 
EASTERLIES...AND THIS IS HELPING TO PRODUCE SCATTERED TSTMS OVER 
SRN MEXICO...GUATEMALA...AND EL SALVADOR. ADDITIONAL SHOWERS/ 
TSTMS ARE LOCATED ALONG THE COASTS OF NICARAGUA...COSTA RICA... 
AND PANAMA.

W OF 110W...
A LONG UPPER LEVEL RIDGE AXIS EXTENDS FROM FAR NW MEXICO SW TO 
NEAR 20N135W...SEPARATING DEEP TROPICAL MOISTURE TO ITS SE FROM 
STRONG SUBSIDENCE NEAR IT AND TO ITS NW. THE FLOW TO ITS SE IS 
PRIMARILY EASTERLY AND IS RESPONSIBLE FOR PRODUCING THE STRONG 
SHEAR OVER T.S. DALILA. THIS FLOW IS ALSO ADVECTING MUCH OF THE 
MOISTURE OVER THE ERN PARTS WWD TO ABOUT 130W. HOWEVER... 
LOW-LEVEL CONVERGENCE ALONG THE ITCZ IS STRONGEST E OF 120W AND 
THAT IS WHERE MOST OF THE DEEP CONVECTION LIES. A SHARP UPPER 
TROUGH AND ASSOCIATED FRONTAL BOUNDARY HAVE STALLED JUST NW OF 
THE REGION WITH THE SUBTROPICAL RIDGE SUPPRESSED...KEEPING THE 
EASTERLY TRADES LARGELY BELOW 20 KT.
 
$$
BERG