000
AXPZ20 KNHC 120921
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC THU JUL 12 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 
0845 UTC.

...TROPICAL WAVES...

TROPICAL WAVE IS ALONG 90W N OF 7N MOVING W 10 TO 15 KT. 
ISOLATED CONVECTION NEAR AXIS BUT NO ORGANIZATION.

TROPICAL WAVE IS ALONG 103W N OF 7N MOVING W 10 TO 15 KT. 
SCATTERED CONVECTION NEAR AXIS BUT NO ORGANIZATION. 
  
TROPICAL WAVE IS ALONG 117W FROM 6N TO 14N MOVING W 10 TO 15 KT. 
SCATTERED STRONG CONVECTION JUST AHEAD OF AXIS BUT NOT ORGANIZED.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 10N83W 7N90W 12N103W 11N111W 12N117W 
9N123W 12N133W 9N140W. SCATTERED MODERATE CONVECTION WITHIN 45 
NM EITHER SIDE OF A LINE FROM 8N79W TO 8N85W TO 6N89W TO 8N94W. 
ISOLATED STRONG NEAR 12N105W. SCATTERED MODERATE FROM 10N TO 14N 
BETWEEN 108W AND 113W. SCATTERED STRONG WITHIN 30 NM OF A LINE 
FROM 11N118W TO 9N125W AND FROM 12N129W TO 9N140W. 

.SCATTERED STRONG CONVECTION NEAR 13N94W AND ALONG THE MEXICAN 
COAST FROM 15N98W TO 17N102W.

...DISCUSSION...

A LARGE CYCLONIC CIRCULATION ALONG 130W CENTERED NEAR 37N HAS 
BEEN STATIONARY THE PAST SEVERAL HRS. MID LEVEL RIDGING 
CONTINUES OVER THE SW CONUS EXTENDING SE BUT WEAKER THAN IN 
PREVIOUS DAYS. AN INVERTED TROUGH WAS ALONG 109W S OF 30N 
DRIFTING W. ON THE SURFACE TONIGHT THE PACIFIC RIDGE HAS 
SEPARATED INTO TWO CENTERS..ONE NEAR 29N123W AND THE OTHER NW OF 
THE AREA. IN BETWEEN LIES A TROUGH ALONG 130W. AN INVERTED 
TROUGH ALONG 125W WAS DRIFTING W AND IS FORECAST TO DISSIPATE. 
WINDS ALONG THE BAJA COAST HAVE INCREASED SOME AND QUIKSCAT AND 
SSMI SHOW 15 TO 20 KT FROM THE NW. GAP WINDS W OF NICARAGUA WERE 
MOSTLY LIGHT WHILE CROSS EQUATORIAL SLY WINDS WERE MOSTLY 15 TO 
20 KT S OF 10N. 

LATER DAY 1 LITTLE CHANGE TO THE OVERALL PICTURE AT MID LEVELS. 
THE STRONG TROUGH ALONG 130W TRIES TO MOVE EWD BUT A MID LEVEL 
RIDGE OVER THE SW CONUS REFUSES TO BUDGE. THE INVERTED TROUGH 
ALONG 109W EARLIER DRIFTS TO 111W WHILE A SECOND INVERTED TROUGH 
ALONG 130W IS MOVING SLOWLY WWD. ON THE SURFACE LATER DAY 1 THE 
TROUGH ALONG 130W LIFTS NE AND DISSIPATES. WEAK HIGH PRES NEAR 
30N122W WILL PRODUCE A LIGHT TO MODERATE NW WINDS ALONG THE BAJA 
COAST. GAP WINDS INCREASE W OF NICARAGUA WITH THE GFS MODEL 
SHOWING ELY WINDS 20 TO 25 KT WITH SEAS TO 9 FT. CROSS 
EQUATORIAL SLY WINDS WILL CHANGE LITTLE..REMAINING 15 TO 20 KT.

FOR DAY 2 THE STRONG MID LEVEL TROUGH N OF THE AREA APPEARS TO 
RETROGRADE WWD TO ALONG 135W. THE MID LEVEL RIDGE OVER THE SW 
CONUS STRENGTHENS SOME AND REFUSES TO GIVE GROUND. WEAKENING 
INVERTED TROUGH ALONG 115W DRIFTING W. ON THE SURFACE DAY 2 A 
WEAK RIDGE WILL EXTEND FROM 24N140W TO 30N124W WITH LITTLE 
CHANGE TO WINDS ALONG THE BAJA COAST. THE USUAL NE TRADES WILL 
BE CONFINED TO S OF 20N W OF 110W TO 20 KT. A COLD FRONT APPEARS 
ON THE HORIZON MOVING TO 140W WITH WINDS TO 20 KT. GAP WINDS 
BETWEEN 10N TO 15N EXTEND W TO 100W..ENHANCED BY ACTIVITY ON THE 
ITCZ. WINDS WILL CONTINUE ELY 15 TO 20 KT. CROSS EQUATORIAL SLY 
WINDS WILL REMAIN ABOUT THE SAME..ALTHOUGH THE GFS MODEL SHOWS 
SOME INCREASE E OF 95W TO 20 TO 25 KT. 

$$
RRG