000
AXPZ20 KNHC 162149
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC TUE MAY 17 2006

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2115 UTC.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 6N77W 8N100W 6N120W 6N140W. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION WITHIN 150 NM EITHER SIDE OF 
AXIS FROM 77W TO 85W AND WITHIN 60 NM EITHER SIDE OF AXIS FROM 95W 
TO 100W.  WIDELY SCATTERED MODERATE CONVECTION WITHIN 175 NM EITHER 
SIDE OF AXIS FROM 100W TO 117W.

...DISCUSSION...

N OF 20N...
MIDDLE TO UPPER LEVEL TROUGH...RIDGE...TROUGH PATTERN COVERS THE 
NORTHERN PORTION OF THE DISCUSSION AREA.  FROM W TO E...A LARGE AND 
VIGOROUS MID/UPPER LEVEL TROUGH LIES W OF 130W WITH ASSOCIATED MOIST 
SWLY MID/UPPER LEVEL FLOW COVERING MUST OF THE W PART OF THE AREA. A 
WEAK AND NARROW RIDGE EXTENDS N ALONG 125N.  FARTHER E...SMALL UPPER 
LEVEL LOW IS SEEN OVER N BAJA WITH ASSOCIATED TROUGH EXTENDING SWD 
TO S BAJA. DIFFLUENT FLOW IS OBSERVED E OF THE TROUGH GENERATING 
CLOUDINESS AND SHOWERS/TSTMS OVER THE HIGHER TERRAIN OF INTERIOR 
MEXICO N OF 20N.  AT THE SURFACE...COLD FRONT PREVIOUSLY OVER THE NW 
PART OF THE DISCUSSION AREA HAS DISSIPATED WITH THE SUBTROPICAL 
RIDGE BEGINNING TO BUILD BACK ACROSS THE AREA FROM 32N130W 18N110W. 
ELSEWHERE...A COLD FRONT IS LOCATED W OF THE AREA AND IS EXPECTED TO 
MOVE INTO THE NW PART OF THE DISCUSSION WITHIN 24 HOURS AS THE LARGE 
UPPER TROUGH SHARPENS AND A CUT-OFF LOW FORMS JUST NW OF THE AREA. 
THE RIDGE AND SOUTHERN CALIFORNIA TROUGH ARE FORECAST TO REMAIN NEAR 
STATIONARY. 

S OF 20N...
THE MAIN FEATURE OVER THE TROPICAL PACIFIC IS AN E/W ORIENTED 
RIDGE EXTENDING FROM 12N140W TO 16N110W.  MODERATE SUBSIDENCE IS 
OBSERVED ALONG THE RIDGE AXIS TO 10N CREATING MOSTLY FAIR CONDITIONS 
N OF THE ITCZ. ISOLATED TO WIDELY SCATTERED CLUSTERS OF CONVECTION 
ARE LOCATED ALONG THE ITCZ BUT THERE IS NO SIGNIFICANT UPPER SUPPORT 
FOR ENHANCED ACTIVITY.  FURTHER E...A SHARP MID/UPPER LEVEL TROUGH 
AXIS EXTENDS FROM THE SW COAST OF MEXICO JUST W OF ACAPULCO INTO THE 
PACIFIC ALONG 18N102W TO 11N108W. EAST OF THE TROUGH A MOIST SWLY 
FLOW IS ADVECTING MID/HIGH LEVEL MOISTURE NWD ACROSS EASTERN 
MEXICO...CENTRAL AMERICA...NW CARIBBEAN AND INTO EASTERN GULF OF 
MEXICO. SOME OF THIS MOISTURE IS BEING ADVECTED FARTHER N AHEAD OF A 
STRONG TROUGH THAT IS MOVING SE ACROSS WRN GULF OF MEXICO.  
ADDITIONALLY...DIFFLUENT FLOW ON THE EQUATORWARD SIDE OF THE TROUGH 
AXIS CONTINUES TO ENHANCE ITCZ CONVECTION BETWEEN 95W AND 105W. THE 
AREA OF LOW PRESSURE PREVIOUSLY EMBEDDED WITHIN THIS REGION OF 
ENHANCED CONVECTION OVER THE WEEKEND HAS SINCE DISSIPATED WITH NO 
SIGNS OF REGENERATION.  A SECOND AREA OF ENHANCED ITCZ CONVECTION IS 
LOCATED E OF 85W WHERE A MID/UPPER LEVEL HIGH IS CENTERED OVER NW 
COLOMBIA NEAR 9N74W. ASSOCIATED RIDGE AXIS EXTENDS W ALONG 9N TO 
NEAR 100W. THE STRONGEST AND MOST NUMEROUS ACTIVITY CURRENTLY 
EXTENDS FROM THE COAST OF COLOMBIA TO 85W AND IS AFFECT MOST OF 
PANAMA AND PORTIONS OF COSTA RICA.

$$
RHOME