000
AXPZ20 KNHC 192152
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON MAY 19 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 2100 UTC.

...TROPICAL WAVES...
TROPICAL WAVE ALONG 92W FROM 04N-12N MOVING W 15 KT WITH 
SCATTERED CONVECTION WITHIN 150 NM OF INTERSECTION WITH ITCZ.
LITTLE DEVELOPMENT EXPECTED OF SYSTEM AS UPPER ENVIRONMENT DOES 
NOT LOOK FAVORABLE WITHIN NEXT 24-36 HRS. 

...ITCZ ALONG...
08N77W TO 08N82W TO 09N88W TO 09N97W TO 12N103W 10N118W TO 
05N140W.  SCATTERED MODERATE CONVECTION WITHIN 150 NM OF AXIS
E OF 92W.  SCATTERED TO NUMEROUS MODERATE ISOLATED STRONG 
CONVECTION WITHIN 180 NM OF AXIS FROM 100W TO 103W. 

...DISCUSSION...
MID TO UPPER LEVEL TROUGH EXTENDS FROM 32N135W TO CYCLONIC 
VORTEX AT 25N139W THEN W OF AREA AT 16N140W.  LARGE SWATH OF 
TRPCL MOISTURE 6-8 DEG WIDE ADVECTED N-NE BY 85 KT JET STREAM 
FROM 08N140W TO 32N128W.  NARROW RIDGE DOWNSTREAM WITH 
ANTICYCLONE NEAR 11N122W SITS AHEAD ON PATH OF WEAK SURFACE 
TROUGH PRODUCING UPPER LEVEL DIFFLUENCE AND ENHANCING SCATTERED 
DEEP CONVECTION ALONG INTERSECTION OF ITCZ AND TROUGH.  NO 
ORGANIZED CONVECTION OBSERVED AT THIS TIME...BUT STRENGTHENING 
IS PROBABLE DUE TO THE FAVORABLE CONDITIONS ALOFT. 

MID TO UPPER LEVEL TROUGH EXTENDS FROM CYCLONIC VORTEX OVER TIP 
OF SRN BAJA CALIFORNIA TO 15N117W.  MODERATE TO STRONG 
SUBSIDENCE AROUND BASE OF TROUGH CAUSING DRY AIR MASS FROM RIDGE 
AXIS AT 123W TO W COAST OF MEXICO.  JUST S OF TROUGH BASE...WEAK 
DEFORMATION ZONE AT THE WRN EDGE OF CARIBBEAN RIDGE SUPPLIES 
GOOD DIFFLUENCE ALOFT ENOUGH TO ENHANCE DEEP CONVECTION ALONG 
SURFACE TROUGH ALONG 104W FROM 06N-15N.  NO ORGANIZATION 
OBSERVED AT THIS TIME...BUT STRENGTHENING IS PROBABLE DUE TO THE 
FAVORABLE CONDITIONS ALOFT. 

ELSEWHERE AT THE SURFACE...
WEAK HIGH PRES CENTER 1021 MB AT 31N132W HAS RIDGE EXTENDING TO 
15N105W.  WITH HIGH PRES DISSIPATING WITHIN 24 HRS...NE TRADES 
DIMINISH BELOW 20 KT AND SEAS SUBSIDE UNDER 8 FT.  LONG NLY 
FETCH OF HIGH PRES EVENTUALLY PRODUCE LONG PERIOD SWELLS 
REACHING BASIN N OF 28N W OF 128W BY END OF FORECAST PERIOD.    

$$
WALLY BARNES