000
AXPZ20 KNHC 160338
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED OCT 15 2008

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 
0300 UTC.

...TROPICAL WAVES...
NONE.

...ITCZ...
AXIS ALONG 09N84W TO 11N100W TO 08N115W TO 09N129W TO 08N140W. 
SCATTERED MODERATE CONVECTION WITHIN 180 NM S OF WAVE AXIS 
BETWEEN 85W AND 96W. AN ORGANIZED CLUSTER OF MODERATE CONVECTION 
COVERS AN AREA WITHIN 30 NM OF 10.5N124W. SCATTERED MODERATE 
CONVECTION IS WITHIN 90 NM S OF AXIS BETWEEN 134W AND 137W AND 
IS WITHIN 90 NM EITHER SIDE OF AXIS W OF 137W. 

...DISCUSSION...
A PERSISTENT SURFACE RIDGE OVER THE NE PACIFIC BUBBLES SOUTHWARD 
INTO THE NW PART OF THE DISCUSSION AREA. WITH THE UPPER-LEVEL 
PATTERN EXPECTED TO BE RATHER PROGRESSIVE OVER THE NEXT COUPLE 
DAYS...THE SURFACE RIDGE SHOULD MOVE EASTWARD AND WILL APPROACH 
THE W COAST OF THE CONUS AND BAJA CALIFORNIA. THE ENHANCED 
PRESSURE GRADIENT BETWEEN THE SURFACE RIDGE AND RELATIVE LOW 
PRESSURE TO THE E WILL GENERATE STRONG SURFACE WINDS AND N 
SWELLS OF UP TO 9 FT OVER THE FAR NW PORTIONS OF THE AREA OVER 
THE NEXT DAY. AS THE SURFACE RIDGE CONTINUES TO SPREAD EASTWARD 
...THE RESULTING PRESSURE GRADIENT OVER THE FORECAST AREA SHOULD 
EVENTUALLY DIMINISH...LEADING TO DECREASING WINDS AND SUBSIDING 
WAVE HEIGHTS. THE ONLY EXCEPTION WILL BE OVER FAR SW PORTIONS OF 
THE AREA LATE FRIDAY...WHERE SEA HEIGHTS OF 8 TO 9 FT IN SW TO W 
SWELL WILL PROPAGATE NORTHWARD FROM A SOUTHERN HEMISPHERIC STORM 
SYSTEM.

ELSEWHERE ACROSS THE REGION...A SURFACE RIDGE WILL CONTINUE TO 
BUILD S INTO MEXICO IN THE WAKE OF A WEAKENED SURFACE FRONT. 
WITH A PRE-EXISTING...BROAD SURFACE PRESSURE TROUGH S OF THE 
GULF OF TEHUANTEPEC...ENHANCED BY PRESSURE FALLS WITH THE 
APPROACH OF TROPICAL DEPRESSION 16...NW TO N WINDS OF 20 TO 30 
KT WILL CONTINUE TO DEVELOP OVER THE GULF OF TEHUANTEPEC OVER 
THE NEXT COUPLE DAYS AND WILL LIKELY PEAK IN 48 HOURS. ALSO OF 
NOTE...NW WINDS OVER THE GULF OF CALIFORNIA FROM YESTERDAY HAVE 
SUBSIDED BELOW 20 KT NOW THAT THE SURFACE FRONT WHICH PASSED THE 
NORTHERN GULF OF CALIFORNIA HAS WEAKENED.

FINALLY...A 1010 MB SURFACE LOW NEAR 10.9N126.5W IS EXPECTED TO 
WEAKEN OVER THE NEXT DAY AS IT MEANDERS SLOWLY WESTWARD. AN 
ORGANIZED CLUSTER OF MODERATE CONVECTION COVERS AN AREA WITHIN 
30 NM OF 10.5N124W WITH SOME ENHANCEMENT FROM THE ITCZ...WHICH 
IS DISPLACED WELL TO THE E OF THE LOW CENTER IN RESPONSE TO 
STRONG SOUTHWESTERLY SHEAR. ALSO...A WEAK SURFACE TROUGH 
AXIS...THE REMNANTS OF A PREVIOUS TROPICAL WAVE...IS LOCATED 
FROM 9N TO 12N ALONG 103W...AND IS RATHER CONVECTIVELY INACTIVE 
IN ONLY A WEAKLY UNSTABLE ENVIRONMENT.

$$
COHEN/KIMBERLAIN