000
AXPZ20 KNHC 190331
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SUN AUG 19 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 87.5W HAS BEEN MOVING W AT 15 KT OVER THE 
PAST 24 HOURS. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS 
ENHANCED IN THE E PAC ALONG THE WAVE AXIS AT 10N.

TROPICAL WAVE IS ESTIMATED ALONG 111.5W AND MOVING W AT 8 TO 10 
KT. A NNW TO SSE ORIENTATED TROUGH IS ALSO IN THE AREA FROM 
24N114W TO 15N110W. A SURFACE LOW IS NEAR 19.5N110.5W ESTIMATED 
AT 1007 MB BUT IS DRIFTING WNW TOWARDS COOLER SEA SURFACE 
TEMPERATURES. A LARGE AREA OF MODERATE CONVECTION WITH A FEW 
STRONG CELLS WITHIN 360 NM EITHER SIDE OF LINE 5N102W 22N114W.

A TROPICAL WAVE ALONG 135W FROM 6N TO 16N HAS MOVED W AT 10 KT 
OVER THE PAST 24 HOURS. A WEAK CYCLONIC SWIRL IS NOTED WITHIN 
THE ITCZ WITH SCATTERED MODERATE CONVECTION ENHANCED AT 
10N137W...BUT IS WEAKENING AT THE MOMENT.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 10N85W 9N90W 17N103W 11N120W 
11N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 
120 NM EITHER SIDE OF LINE 10N85W 7N94W...AND WITHIN 360 NM 
EITHER SIDE OF LINE 5N102W 22N114W.

...DISCUSSION...

AN UPPER TROUGH DOMINATES THE E PAC EXTENDING S INTO THE 
DISCUSSION AREA FROM 32N127W TO AN UPPER CYCLONE NEAR 
17N131W...SQUEEZED BETWEEN TWO UPPER RIDGES. THE UPPER 
ANTICYCLONE TO THE W IS NEAR 24N145W WITH A RIDGE EXTENDING E TO 
A CREST NEAR 26N134W. AN UPPER ANTICYCLONE IS OVER OLD MEXICO 
NEAR 30N110W WITH A RIDGE EXTENDING SW TO A GENTLE CREST ALONG 
14N116W 22N123W 32N122W. UPPER DIFFLUENCE FROM THIS RIDGE IS 
ENHANCING THE CONVECTION OVER THE PAC N OF THE ITCZ BETWEEN 100W 
AND 120W WITH THE RESULTANT DEBRIS MOISTURE MOSTLY N OF 7N 
BETWEEN 105W AND 120W...BUT SOME OF THE DEBRIS MOISTURE IS NOW 
ADVECTED SW TO THE EQUATOR BETWEEN 100W AND 120W. 
OTHERWISE...DRY UPPER AIR IS NOTED OVER THE DISCUSSION AREA N OF 
12N W OF 124W. 

AN UPPER TROUGH EXTENDS S FROM A CYCLONE OVER THE EASTERN GULF 
OF MEXICO NEAR 25N86W TO ANOTHER SMALL UPPER CYCLONE AT 16N90W 
WHICH APPEARS TO BE FILLING RAPIDLY. THE UPPER FLOW IS NE OVER 
THE TROPICS E OF 105W.
 
ELSEWHERE AT THE LOW LEVELS A RIDGE EXTENDS ALONG 31N140W 
23N117W. 

$$
NELSON