000
AXPZ20 KNHC 130328
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC FRI JUL 13 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 
0315 UTC.

...TROPICAL WAVES...

TROPICAL WAVE ALONG 82W N OF 3N IS MOVING W 12 KT. SLIGHT 
CYCLONIC TURNING NOTED OVER LAND NEAR 8N82W WITH SHOWERS AND 
TSTMS NOTED ALONG BOTH COASTS OF COSTA RICA.  

TROPICAL WAVE IS ALONG 94W N OF 5N MOVING W AT 10 KT. THE WAVE 
ALTHOUGH BROAD CYCLONIC TURNING IS NOTED THERE IS LITTLE 
CONVECTIVE ACTIVITY.

TROPICAL WAVE IS ALONG 108W N OF 6N. BROAD CYCLONIC TURNING IS 
NOTED AND THE WAVE AXIS WAS ANALYZED A LITTLE FURTHER W WITH A 
WEAK SURFACE LOW NEAR 12N ALONG THE WAVE. CONVECTION IS ENHANCED 
N OF 10N WITHIN 60 NM EITHER SIDE OF THE WAVE AXIS. THE LOW PRES 
ASSOCIATED WITH THIS WAVE COULD CONTINUE TO ORGANIZE AND CYCLONE 
FORMATION IS POSSIBLE OVER THE NEXT FEW DAYS.   

TROPICAL WAVE IS ALONG 121W FROM 5N TO 15N IS MOVING W 12 KT. 
WEAK CYCLONIC TURNING NOTED MAINLY ALONG THE AXIS AT 11N WHERE 
THE DEEPEST CONVECTION CONTINUES TO FLARE.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 9N77W 9N85W 7N90W 12N108W 10N140W. 
SCATTERED MODERATE ISOLATED STRONG WITHIN 90NM EITHER SIDE LINE 
7N87W 7N97W AND LINE 11N107W 12N120W 8N125W 12N131W.

...DISCUSSION...

A MID TO UPPER LEVEL TROUGH IS OVER THE NW PORTION WITH MEAN 
AXIS ALONG 32N128W 23N125W...WITH A SURFACE COLD FRONT 
APPROACHING THE NW PORTION. THE UPPER TROUGH IS EXPECTED TO LIFT 
NE AND THE SURFACE FRONT WILL LOSE ITS SE PUSH STALLING AND 
DISSIPATING OVER THE NW WATERS WITHIN TWO DAYS. 

UPPER MOISTURE IS SPREADING SE OVER THE AREA OF N OF 24N W OF 
130W. OTHERWISE DRY UPPER AIR IS INDICATED N OF 14N W OF 121W. 
AN UPPER ANTICYCLONE IS OVER THE GULF OF MEXICO NEAR 27N92W WITH 
A RIDGE EXTENDING W ACROSS OLD MEXICO TO A CREST NEAR 26N120W. 
UPPER DEBRIS MOISTURE...MAINLY FROM ITCZ CONVECTION BETWEEN 99W 
AND 110W...CONTINUES TO SPREAD N ALONG THE W PERIPHERY OF THE 
RIDGE OVER THE UPPER LEVELS OF THE CONUS DESERT SW. 

ELSEWHERE AT THE SURFACE...HIGH PRES IS CENTERED NEAR 31N128W 
1018 MB...BUT OVERALL RIDGING IN THE EPAC REMAINS WEAK. 

GAP WINDS...ELY WINDS 20 TO 25 KT IN THE GULF OF PAPAGAYO 
EXPECTED TO PERSIST THROUGH FRI THEN RELAX INTO SAT. 

$$
NELSON