000
AXPZ20 KNHC 240324
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC THU SEP 23 2010

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 
0245 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 12N96W TO 10N140W. SCATTERED 
MODERATE CONVECTION IS NOTED N OF 06N BETWEEN 82W AND 92W...AND 
ALSO WITHIN 60 NM EITHER SIDE OF A LINE FROM 10N104W TO 13N111W 
TO 10N115W...AND ALSO A LINE FROM 09N124W TO 11N132W.

...DISCUSSION...

AN UPPER LEVEL ANTICYCLONE IS OVER THE OLD MEXICO AND TEXAS 
BORDER AT 30N102W WITH A RIDGE EXTENDING SW TO 25N115W. A SECOND 
ANTICYCLONE IS NEAR 29N128W. A CYCLONIC SHEAR AXIS SEPARATES 
THESE ANTICYCLONES ALONG A LINE FROM 32N110W TO 19N140W. AN 
UPPER LEVEL TROUGH IS APPROACHING THE FAR NW CORNER. THE UPPER 
LEVELS APPEAR DRY NW OF LINE 32N104W TO 12N124W. TO THE SE OF 
THE SAME LINE THE UPPER LEVEL NE TO E DIFFLUENT FLOW SUPPORTED 
CONVECTION OVER CENTRAL AMERICA THU AFTERNOON. THE RESULTANT 
DEBRIS MOISTURE NOW IS SPREADING SW COVERING THE UPPER LEVELS E 
OF 115W.  

AT THE LOW LEVELS A SURFACE HIGH IS NEAR 28N143W 1020 MB WITH A 
BROAD RIDGE DOMINATING THE SUBTROPICS N OF 15N W OF 120W. A 
TROPICAL LOW PRES IS 15.5N 102W AND IS MOVING W. CONVECTION 
APPEARED TO BE ORGANIZING INTO BANDS ON THU...BUT THE CONVECTION 
HAS SINCE DIMINISHED. MONSOONAL SW FLOW CONTINUES S OF A LINE 
ALONG 15N95W TO 12N115W TO 10N140W WITH WINDS AT 15 TO 20 KT 
WITHIN ABOUT 480 NM S OF THE LINE. A SECOND SURFACE LOW 
CONTINUES TO SPIN ALONG THIS BOUNDARY NEAR 11N131W WITH A 180 NM 
ENVELOPE OF CYCLONIC FLOW AT 20 KT. 

THE WAVEWATCH III MODEL INDICATES LONG PERIOD SWELLS DRIVING 
COMBINED SEAS HEIGHTS TO 12 FT WILL MOVE INTO THE FAR NW WATERS 
LATE THIS WEEKEND REACHING THE NORTHERN BAJA PENINSULA MON 
NIGHT.

$$
NELSON