000
AXPZ20 KNHC 091602
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC FRI MAY 09 2008

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 
1500 UTC.

...ITCZ...
INTERTROPICAL CONVERGENCE ZONE ALONG THE LINE...08N82W TO 
05N100W TO 08N112W TO 05N112W TO 08N128W TO 02N140W.  SCATTERED 
MODERATE TO ISOLATED STRONG CONVECTION WITHIN 180 NM S OF THE 
ITCZ AXIS BETWEEN 81W AND 115W.  SCATTERED MODERATE CONVECTION 
FROM 10N TO 14N BETWEEN 111W AND 116W. SCATTERED MODERATE 
CONVECTION ALSO WITHIN 120 NM N OF AXIS BETWEEN 138W AND 140W.

...DISCUSSION...

A SERIES OF SHORTWAVE TROUGHS PUSHING INTO THE WESTERN U.S. THE 
NEXT FEW DAYS SHOULD REINFORCE A MEAN LONGWAVE TROUGH POSITION 
EXTENDING FROM THE WEST COAST THROUGH A CLOSED LOW CENTERED NEAR 
24N135W. THIS PATTERN SHOULD ALLOW BRISK NW TO N FLOW TO 
CONTINUE N OF ABOUT 28N BETWEEN 118W AND 132W TODAY BEFORE 
DECREASING OVER THE WEEKEND. EXPECT SEAS OF 8 TO 10 FT IN A MIX 
IN MOSTLY NW SWELL TO CONTINUE ARRIVING WITHIN A FEW HUNDRED 
MILES W OF THE NORTHERN AND CENTRAL BAJA CALIFORNIA PENINSULA. 
PEAK SWELL IS EXPECTED LATE TODAY AND EARLY SAT...WITH SEAS 
GRADUALLY SUBSIDING LATER THIS WEEKEND. EARLY NEXT 
WEEK...ANOTHER SHORTWAVE DISTURBANCE ALOFT SHOULD AGAIN INDUCE N 
WINDS TO 20 KT OVER THE SAME AREA.

NEXT...ENHANCED SURFACE HIGH PRESSURE IN THE WAKE OF THE 
MEAN TROUGH OVER THE WESTERN U.S. SHOULD KEEP ABOVE AVERAGE 
TRADES BLOWING GENERALLY FROM ABOUT 6N TO 27N W OF ABOUT 122W. 
MODEL GUIDANCE SUGGESTS THAT THE COVERAGE AND INTENSITY OF THE 
TRADES SHOULD GRADUALLY DECREASE OVER THE WEEKEND...CAUSING SEAS 
OF 8 TO 10 FT IN MIXED NE WIND WAVES AND S SWELL OVER THE FAR 
SOUTH PART OF THIS AREA TO SLOWLY SUBSIDE TO 6 TO 7 FT BY SUN.

OTHERWISE...A GROUP OF SW SWELL WITH ORIGINS FROM THE SOUTHERN 
HEMISPHERE MID-LATITUDES SHOULD PROPAGATE INTO THE TROPICAL 
EASTERN PACIFIC STARTING FROM TODAY AND LASTING INTO THE 
WEEKEND. SEAS OF SLIGHTLY HIGHER THAN 8 FT SHOULD CROSS THE 
EQUATOR BETWEEN THE COLOMBIAN AND ECUADORAN COASTS AND 130W 
...REACHING AS FAR N AS 10N BY SAT. SW SWELL SHOULD SLOWLY 
SUBSIDE GOING INTO EARLY NEXT WEEK.

ELSEWHERE...SATELLITE IMAGERY SHOWS DISPARATE AREAS OF 
CONVECTION BETWEEN THE ITCZ AND 14N BETWEEN 110W AND 115W. ONE 
AREA BEING PUSHED NORTHWARD BY A STRONG SOUTHERLY MID- TO 
UPPER-LEVEL FLOW IS CONCENTRATED NEAR 13N113W...NEARLY 
COINCIDENT WITH A POORLY-DEFINED MID-LEVEL CYCLONIC CIRCULATION. 
HOWEVER...MORNING QUIKSCAT DATA REVEALS NO CORRESPONDING 
LOW-LEVEL CIRCULATION.  TO THE SOUTH...CHAOTIC CONVECTIVE 
ELEMENTS WITHIN THE ITCZ SURROUND A WEAK...ELONGATED AREA OF
LOW PRESSURE ALONG THE ITCZ.  LITTLE...IF ANY...DEVELOPMENT IS 
EXPECTED OF THIS AREA SINCE AN UPPER-LEVEL CURRENT OF STRONG 
WESTERLY FLOW LIES JUST TO THE W. 

FINALLY...SCATTEROMETER DATA THIS MORNING INDICATE THAT WINDS OF 
20 KT CONTINUE DOWNSTREAM OF THE GULF OF PAPAGAYO. THESE WINDS 
HAVE FLUCTUATED THE LAST FEW DAYS...POSSIBLY A RESULT OF LOCAL 
DIURNAL CIRCULATIONS.  MODEL GUIDANCE SUGGESTS THAT THIS CURRENT 
GAP WIND EVENT SHOULD CONCLUDE...HOWEVER...BY THIS EVENING.


$$
KIMBERLAIN/BELL