000
AXPZ20 KNHC 312205
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON MAR 31 2008

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 2115 UTC.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 06N77W 03N100W 08N121W 04N140W.  
SCATTERED MODERATE WITHIN 90 NM EITHER SIDE OF AXIS BETWEEN 102W 
AND 108W AND WITHIN 240 NM S OF AXIS BETWEEN 108W AND 118W.

...DISCUSSION...
A SHARP MID TO UPPER SHORTWAVE TROUGH HAS MOVED EASTWARD ALONG 
138W SUPPORTING A COLD FRONT THAT IS ALONG THE NW PORTION OF THE 
DISCUSSION AREA FROM 30N139W TO 29140W. ALL OF THE ASSOCIATED 
CONVECTION LIES N OF THE REGION...WHERE THE GREATEST LIFT AND 
DIVERGENCE ALOFT EXISTS. A LARGE UPPER HIGH IS SITUATED IN THE 
TROPICAL EPAC NEAR 15N103W AND A WEAKER HIGH IS LOCATED NEAR 
5N136W. STRONG SW FLOW ALOFT...REACHING 100 KT AT BAJA 
CALIFORNIA...BETWEEN THE HIGHS AND THE TROUGH IS ADVECTING A 
PLUME OF MOISTURE...MAINLY IN THE FORM OF MID-HIGH LEVEL 
CLOUDS...ACROSS SOUTHERN BAJA CALIFORNIA AND INTO NORTHWESTERN 
MAINLAND MEXICO.  SUBSIDENCE PREVAILS ELSEWHERE...ESPECIALLY N 
OF 10N E OF 110W DUE TO UPPER CONVERGENCE.  THIS CORRESPONDS 
WITH THE RATHER ANEMIC CONVECTION WITH THE ITCZ THROUGHOUT MOST 
OF THE REGION EXCEPT BETWEEN 102 AND 118W. 

AT THE SFC...SUBTROPICAL RIDGING IS WEAKENING DUE TO A 
SOUTHEASTWARD MOVING 1011 MB LOW NEAR 38N138W. THIS 
HAS ALLOWED NE/E TRADES TO SLACKEN ACROSS THE REGION WITH 20 KT 
WINDS MAINLY CONFINED FROM 7N-18N W OF 125W.  THE MAIN WIND 
EVENT IN THE AREA DURING THE NEXT THREE DAYS WILL BE ASSOCIATED 
WITH THE AFOREMENTIONED COLD FRONT. AS THE FRONT PUSHES FARTHER 
INTO THE REGION...WINDS AROUND 20 TO POSSIBLY 25 KT ARE EXPECTED 
ON EITHER SIDE OF THE FRONT N OF 25N. NW SWELLS WILL BUILD IN 
BEHIND THE FRONT LATE TOMORROW UP TO ABOUT 8 FT.

GULF OF PAPAGAYO...AS SUGGESTED IN THE PREVIOUS DISCUSSION...IT 
APPEARS THAT THE WINDS HAVE DROPPED BELOW 20 KT IN THE AREA...SO 
THIS HAS BEEN REMOVED FROM THE HIGH SEAS FORECAST.

$$
LANDSEA