000
AXPZ20 KNHC 172129
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC FRI SEP 17 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2130 UTC.

...ITCZ...
INTERTROPICAL CONVERGENCE ZONE...FROM 11N127W TO 10N140W. A 
MONSOON TROUGH AXIS EXTENDS FROM 17N105W TO 15N113W TO 11N127W 
...WITH EMBEDDED LOW PRES AS DESCRIBED ABOVE. SCATTERED MODERATE 
TO STRONG EXISTS FROM 12N TO 17N BETWEEN 102W AND 109W. SCATTERED
MODERATE ISOLATED STRONG IS WITHIN 180 NM S OF THE AXIS BETWEEN 
118W AND 123W.

...DISCUSSION...

A SHEARED UPPER TROUGH EXTENDS FROM 30N132W TO JUST NE OF THE 
HAWAIIAN ISLANDS. THIS UPPER TROUGH CONTINUED TO SHEAR OUT TO 
THE NE IN THE FACE OF A RATHER EXTENSIVE ANTICYCLONE AND RIDGE 
WHICH DOMINATED MOST OF THE EAST PACIFIC AND MEXICO WITH THE 
AXIS GENERALLY ALONG 20N. DRY DEEP LAYERED AIR PERSISTS N OF 
20N. ONLY WEAK SHOWERS ARE NOTED ALONG THE ITCZ IN THIS AREA DUE 
TO THE DRY SUBSIDENT AIR ALOFT.

DIFFLUENT NORTHEASTERLY FLOW ALOFT ON THE SOUTH SIDE OF THE 
ANTICYCLONE/RIDGE NOTED ABOVE IS ENHANCING SCATTERED CONVECTION 
ALONG THE MONSOON TROUGH AXIS...FROM 12N TO 17N BETWEEN 100W AND 
110W.  

LATEST SHIP...TAU ARRAY BUOY AND SCATTEROMETER DATA DEPICT A 
WELL DEVELOPED MONSOON TROUGH AXIS EXTENDING FROM OFF THE COAST 
OF MEXICO NEAR 13N100W TO 15N114W TO 11N127W WITH WINDSAT AND 
ASCAT DATA SHOWING 15 TO 20 KT SW WINDS BETWEEN 100W AND 115W. 
THERE WERE SEVERAL WEAK SURFACE LOWS NOTED ALONG THE MONSOON 
TROUGH NEAR 13N105W...14N115W AND 11N127W WITH THE MOST 
SIGNIFICANT LOW NEAR 14N115W. GFS AND ECMWF MODELS MAINTAIN THE 
LOW NEAR 14N115W AS A WEAK SYSTEM THROUGH THE NEXT SEVERAL DAYS 
WITH SPORADIC CONVECTION. LONG PERIOD SW SWELL OF 14 TO 17 
SECONDS WILL ADD TO LOCALLY DEVELOPED SEAS IN THE AREA OF THE 20 
KT SW WINDS S OF MONSOON TROUGH TO PRODUCE SEAS UP TO 12 FT 
THROUGH THE NEXT 48 HOURS.

$$
COBB