000
AXPZ20 KNHC 100938
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC TUE JUL 10 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 DEPRESSION 4-E 1006 MB AT 117.7N 119.3W AT 0300 UTC 
MOVING NW AT 7 KT.  MAXIMUM SUSTAINED WINDS 30 WITH GUSTS TO 40 
KT.  SYSTEM LOST MOST OF ITS DEEP CONVECTION SINCE 0000 UTC ONLY 
TO START NEW CLUSTER ON NW QUADRANT IN LAST TWO HRS.  LOW SHEAR 
ALOFT POSSIBLY EXTENDING SLOW DEMISE OF T.D. 4-E AS IT 
APPROACHES DRIER AIR MASS AND COOLER SST...MODELS FORECAST 
SYSTEM TO WEAKEN NEXT 36 HOURS.

...TROPICAL WAVES...
TROPICAL WAVE N OF 7N ALONG 90W MOVING W 10-15 KT.  NO 
ORGANIZATION NOTED AND LITTLE SIGNIFICANT ASSOCIATED CONVECTION.

...ITCZ...
INTERTROPICAL CONVERGENCE ZONE...9N84W  9N95W  11N100W  9N111W 
11N124W  9N140W.  SCATTERED MODERATE/ISOLATED STRONG CONVECTION 
WITHIN 210 NM OF ITCZ AXIS E OF 117W AND WITHIN 120 NM S OF AXIS 
W OF 132W. 

...DISCUSSION...
BROAD UPPER LEVEL RIDGE WITH CENTER AT 15N136W BRINGS NEW LOAD 
OF TROPICAL MOISTURE INTO E PAC BASIN N OF 22 W OF 130W.  UPPER 
LEVEL NEGATIVELY TILTED TROUGH EMERGES FROM CYCLONIC VORTEX AT 
35N129W TO REACH 32N125W THEN TO 28N115W.  DRY AIR MASS WITHIN 
300 NM OF TROUGH AXIS AND W OF 122W N OF ITCZ.

DOWNSTREAM ANTICYCLONIC CIRCULATION AT 20N114W...PREVIOUSLY 
SUPPORTING DEVELOPMENT OF T.D. 4-E...NOW ONLY ADVECTING MOISTURE 
DEBRIS FROM SYSTEM NE TOWARDS BAJA CALIFORNIA.  RIDGE EXTEND E 
TO REACH COLOMBIA ALLOWING MOISTURE INTO E PAC MAINTAINING VERY 
ACTIVE ITCZ E OF T.D. 4-E.   

AT THE SURFACE...
HIGH PRES 1031 MB AT 41N140W HAS RIDGE EXTEND TO 25N110W AND 
CAUSING MODERATE NE TRADES N OF 20N W OF 130W.

...GAP WINDS...
STRONG TRADES OVER WRN CARIBBEAN CROSS OVER INTO E PAC ALONG 
GULF OF PAPAGAYO WITH 20 KT E WIND LIKELY TO PERSIST NEXT 48 HRS.

$$
WALLY BARNES