000
AXPZ20 KNHC 250924
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SAT AUG 25 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 MOVING W 10-15 KT. CLUSTER OF STRONG 
CONVECTION WITHIN 90 NM OF 8N86W HAS BEEN MAINTAINING ITSELF THE 
PAST SEVERAL HOURS. INDICATIONS OF A POSSIBLE MID LEVEL 
CIRCULATION FROM LATEST SATELLITE PICTURES.  

...ITCZ...
ITCZ AXIS IS ALONG 9N83W 14N96W 14N114W 9N134W 9N140W. CLUSTER 
OF STRONG CONVECTION WITHIN 90 NM OF 8N86W. SCATTERED MODERATE 
FROM 10N TO 16N BETWEEN 94W AND 118W. SCATTERED MODERATE WITHIN 
20 NM EITHER SIDE OF A LINE FROM 11N122W TO 8N136W.

...DISCUSSION...
 
MID LEVEL RIDGE OVER THE SW CONUS TONIGHT BEING SQUEEZED BY A 
TROUGH OVER THE W CENTRAL CONUS. THE RIDGE STILL PRODUCING A 
MODERATE NE AND E WINDS ALOFT OVER THE ERN PACIFIC TO 124W 
TONIGHT. W OF 124W THE MID AND UPPER ATMOSPHERE DRIES OUT AND 
THE MID LEVEL PATTERN WEAKENS. WEAK VORTICITY IMPULSES ARE 
EMBEDDED IN THIS AREA AND DRIFTING W. ONE IS NEAR 27N120W AND 
ANOTHER WEAKER ONE NEAR 28N137W. ON THE SURFACE TONIGHT THE 
PACIFIC RIDGE REMAINS CENTERED NW OF THE AREA AND IS PRODUCING 
WEAK NE TRADES OVER THE AREA N OF 15N W OF 130W. WINDS ALONG THE 
BAJA COAST ARE ALSO LIGHT AS WELL AS GAP WINDS. CROSS EQUATORIAL 
SLY WINDS TO 20 KT ARE EVIDENT S OF 12N E OF 130W ACCORDING TO 
SSMI AND QUIKSCAT IMAGERY. SLY SWELL TO 9 FT CONTINUES TO 
PROPOGATE NWD TO 12N FROM THE SRN HEMISPHERE. 

LATER DAY 1 A WEAKNESS IN THE PRES FIELD AT MID LEVELS WILL 
CONTINUE ALONG 130W. THE MID LEVEL RIDGE OVER THE SW CONUS WILL 
REMAIN STATIONARY. ON THE SURFACE LATER DAY 1 THE PRES GRADIENT 
WILL REMAIN WEAK WITH MIGRATING TRPL WAVES NONE OF WHICH SHOW 
ANY SIGNS OF DEVELOPING. CROSS EQUATORIAL SLY WINDS TO 20 KT 
WITH SLY SWELL TO 9 FT WILL CONTINUE S OF 10N.

FOR DAY 2 THE MID LEVEL WEAKNESS BETWEEN 120W AND 130W CONTINUES 
AND WEAK VORTICITY IMPULSES WILL TRY TO EXPLOIT THE WEAKNESS BY 
MOVING AROUND THE SW CONUS RIDGE THAN HEADING NW. MID LEVEL 
RIDGING JUST NW OF THE AREA SHOWS SIGNS OF STRENGTHENING 
SLIGHTLY. ON THE SURFACE DAY 2 THIS WILL HELP THE PACIFIC RIDGE 
BUT MOST OF IT'S GRADIENT STAYS NW OF THE REGION THUS NE TRADES 
WILL BE MOSTLY LIGHT OVER THE REGION N OF 18N W OF 115W. WINDS 
ALONG THE BAJA COAST WILL REMAIN NWLY AND LIGHT. GAP WINDS 
MOSTLY 10 TO 15 KT. CROSS EQUATORIAL SLY WINDS TO 20 KT WILL 
CONTINUE S OF 10N OVER THE ENTIRE AREA ALONG WITH SLY SWELL TO 9 
FT.












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RRG