000
AXPZ20 KNHC 161513
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC FRI APR 16 2010

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 
1530 UTC.

...ITCZ...

THE ITCZ AXIS EXTENDS FROM 05N77W TO 07N97W TO  05N120W TO 
05N140W. SCATTERED MODERATE FROM 04N TO 07N BETWEEN  87W AND 
96W. SCATTERED MODERATE TO STRONG FROM 01N TO 04N  BETWEEN 118W 
AND 124W...AND FROM 02N TO 05N BETWEEN 126W AND  133W.  
 
...DISCUSSION...

AN UPPER LEVEL CYCLONE IS POSITIONED E OF THE AREA NEAR 32N146W 
WITH AN UPPER TROUGH EXTENDING FROM THE CYCLONE TO 20N150W. A 
110-130 KT JETSTREAM IS OVER THE SUBTROPICS FROM 20N-30N BETWEEN 
140W TO NORTHERN BAJA CALIFORNIA MOVING E. FURTHER E...ANOTHER 
LARGER UPPER LEVEL TROUGH EXTENDS OVER THE EASTERN PORTION OF 
THE AREA FROM THE WESTERN GULF OF MEXICO ACROSS SE OLD MEXICO 
NEAR THE GULF OF TEHUANTEPEC TO NEAR 10N96W. 

TO THE S BETWEEN THE UPPER LEVEL TROUGHS...AN UPPER LEVEL 
ANTICYCLONE IS CENTERED NEAR 14N123W. ANTICYCLONIC FLOW IS N OF 
THE EQUATOR BETWEEN 105W AND 145W. ITCZ CONVECTION IS 
MAINTAINING THIS UPPER LEVEL ANTICYCLONE FROM THE EQUATOR TO 10N.

AT THE SURFACE...THE ABOVE MENTIONED UPPER LEVEL CYCLONE AND 
TROUGH ARE SUPPORTING A 1005 MB LOW NEAR 34N136W WITH A COLD 
FRONT EXTENDING FROM THE LOW CENTER TO 30N144W TO 26N150W TO N 
OF THE HAWAIIAN ISLANDS NEAR 23N160W. S-SW WINDS OF 20 TO 30 KT 
PREVAIL N OF 25N WITHIN 210 NM E OF THE FRONT. EXPECT...THIS 
FRONT TO MOVE E INTO THE AREA AT 140W WITHIN 12 HOURS WITH 
ASSOCIATED SUB GALE FORCE WINDS.

THE PRESSURE GRADIENT BETWEEN THE ITCZ AND 1020 MB HIGH 
POSITIONED NEAR 25N125W IS MAINTAINING NE TRADES OF 20 KT FROM 
08N TO 13N BETWEEN 115W AND 135W. RESULTANT SHORT PERIOD NE WIND 
WAVES ARE COMMINGLING WITH LONG PERIOD NW SWELL AND CROSS 
EQUATORIAL LONG PERIOD SW SWELL THAT HAS BEEN PROPAGATING N 
ACROSS THE DISCUSSION AREA FOR SEVERAL DAYS RESULTING IN 
CONFUSED SEAS WHERE THE DIFFERENT WAVE GROUPS ARE INTERSECTING.

$$
FORMOSA