000
AXPZ20 KNHC 231602
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU SEP 23 2010

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1545 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 14N107W TO 11N118W TO A 1011 MB LOW
NEAR 11N130W TO 10N140W. SCATTERED MODERATE CONVECTION IS WITHIN
60 NM S OF THE AXIS BETWEEN 114W-117W AND BETWEEN 127W-132W.

...DISCUSSION...

AN UPPER LEVEL ANTICYCLONE IS OVER FAR NE MEXICO WITH A RIDGE SW 
TO 24N130W TO 20N140W. TO THE N OF THE RIDGE...A MID/UPPER LEVEL 
TROUGH IS OVER THE FAR NE PORTION OF THE AREA MOVING INLAND THE 
WESTERN U.S. TO THE S OF THE RIDGE...UPPER LEVEL NE TO E 
MODERATE FLOW IS PRESENT WITH A DIFFLUENT FLOW PATTERN 
SUSTAINING CONVECTION E OF ABOUT 109W. UNDERNEATH THIS FLOW 
PATTERN...AN AREA OF DISTURBED WEATHER CONSISTING OF SCATTERED 
STRONG CONVECTION IS S OF MEXICO FROM 13N TO 16N BETWEEN 
99W-105W WITH DEPICTED AS A 1010 MB SURFACE LOW NEAR 15N101W 
MOVING WNW AT ABOUT 8 KT. WINDS OF 20 KT ARE WITHIN 60 NM IN THE 
SOUTHERN SEMICIRCLE OF THE LOW. MODERATE SUBSIDENCE AND 
ASSOCIATED DRY AIR IS BEING CHANNELED SOUTHWESTWARD BETWEEN THE 
ANTICYCLONE OVER NE MEXICO AND AN UPPER LEVEL LOW OVER THE 
WESTERN GULF OF MEXICO TOWARDS THE FAR EASTERN PACIFIC WATERS N 
OF THE AREA OF DISTURBED WEATHER. DEVELOPMENT WITH THE AREA OF 
DISTURBED WEATHER IS EXPECTED TO BE SLOW TO OCCUR OVER THE NEXT 
48 HOURS AS IT TRACKS WNW.

AT THE SURFACE TO LOW LEVELS BROAD HIGH PRESSURE DOMINATES THE 
SUBTROPICS N OF 19N W OF 125W...WITH A NEARLY STATIONARY HIGH OF 
1020 MB W OF THE AREA NEAR 28N144W WITH ITS ASSOCIATED RIDGE 
EXTENDING ESE TO NEAR 28N126W. THE INTERACTION BETWEEN THE RIDGE 
AND BROAD LOW PRES OVER THE EASTERN PORTION OF THE AREA N OF 
26N BETWEEN 115W-120W TO THE BAJA PENINSULA COAST. THIS GRADIENT
WILL RELAX WITH WINDS DIMINISHING TO LESS THAN 20 KT AND SEAS 
SUBSIDING TO LESS THAN 8 FT IN ABOUT 12 HOURS. A 1011 MB LOW IS 
NEAR 11N129W WITH WINDS OF 20 KT WITHIN 120 NM IN THE SW TO W 
SEMICIRCLE WITH SEAS TO 8 FT. GLOBAL MODELS TEND TO MOVE THIS
LOW ENE THROUGH THE NEXT 48 HOURS...BUT MAINTAIN IT RATHER WEAK.
THE LATEST ECMWF SOLN DEVELOPS A COUPLE OF OTHER WEAK LOWS ALONG
THE FAR WESTERN PORTION OF THE ITCZ WITHIN THE NEXT 48 HOURS 
WITH GENERAL MOTION TO THE E. THIS SEEMS PLAUSIBLE GIVEN THAT 
ALREADY OVER THE PAST FEW DAYS SIMILAR WEAK LOWS HAVE BEEN 
OBSERVED ACROSS THIS SAME AREA. ABUNDANT TROPICAL MOISTURE 
CONVERGING ON THE S SIDE OF THE ITCZ E OF ABOUT 130W IS EXPECTED 
TO REMAIN THROUGH AT LEAST THE NEXT 48 HOURS WHILE SW TO W WINDS 
OF 20 KT ARE OCCURRING FROM 8N TO 12N BETWEEN 105W AND 120W. 
THIS AREA IS FORECAST TO EXPAND FROM 8N TO 11N BETWEEN 102W AND
120W IN 48 HOURS.

THE WAVEWATCH III MODEL IS CONSISTENTLY DEPICTING LONG PERIOD 
SWELLS OF POSSIBLY 12 OR 13 FT THAT WILL MOVE INTO THE NW 
SECTION OF THE DISCUSSION AREA THIS WEEKEND...EXTENDING FROM 
SOUTHERN CALIFORNIA TO ROUGHLY 16N140W BY LATE SUN.

$$
AGUIRRE