000
AXPZ20 KNHC 071553
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN APR 07 2013

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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1545 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 
THE MONSOON TROUGH EXTENDS SW FROM THE COAST OF COSTA RICA AT 
09N84W TO 06N93W WHERE SCATTEROMETER WINDS INDICATE A TRANSITION 
TO AN ITCZ. THE ITCZ THEN CONTINUES WSW TO BEYOND 02N140W. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION...CURRENTLY
ACCOMPANIED BY FREQUENT LIGHTNING...IS OBSERVED OVER AND ALONG
THE PACIFIC COAST OF COLOMBIA WITHIN 30 NM OF 05.5N77.5W. SIMILAR
CLUSTERS OF CONVECTION IS NOTED ALONG THE MONSOON TROUGH WITHIN
90 NM EITHER SIDE OF A LINE FROM 08.5N83W TO 06.5N89W...WITHIN
15 NM OF 06.5N94W...AND ASSOCIATED WITH THE ITCZ WITHIN THE
AREA BOUNDED BY 03N TO 08N BETWEEN 99W AND 134W. 
 
...DISCUSSION... 
GULF OF TEHUANTEPEC...LIGHT AND VARIABLE WINDS EXPECTED ACROSS 
THE GULF OF THROUGH THU EVENING...WITH GUIDANCE SUGGESTING 10 TO
15 KT NORTHERLY DRAINAGE WINDS AT SUNRISE FRI. 

GULF OF PAPAGAYO...ENE WINDS ARE EXPECTED TO PULSE AT 15 TO 20
KT LATE EACH NIGHT TILL JUST AFTER SUNRISE EACH MORNING THROUGH
WED MORNING. THE GRADIENT WILL THEN FURTHER RELAX SUPPORTING LIGHT
AND VARIABLE WINDS...WITH THE LATE NIGHT EASTERLY DRAINAGE FLOW 
ONLY AT 10 TO 15 KT ON THU AND FRI. 

GULF OF PANAMA...NORTHERLY WINDS AT 10 TO 15 KT EXPECTED TO
CONTINUE THROUGH TUE...THEN LIGHT AND VARIABLE WINDS EXPECTED
TUE NIGHT THROUGH FRI.

GULF OF CALIFORNIA...SOUTHERLY 5 TO 10 KT WINDS ARE EXPECTED 
ACROSS THE GULF OF CALIFORNIA WATERS THROUGH EARLY TONIGHT...
THEN INCREASING TO 10 TO 15 KT LATE TONIGHT...EXCEPT 15 TO 20 KT
ACROSS THE WATERS N OF 30N. SW TO W WINDS WILL INCREASE TO 20
TO 25 KT ACROSS THE GULF WATERS N OF 29N ON MON WITH S TO SW 
WINDS AT 10 TO 15 KT S OF 29N. THE GRADIENT WILL WEAKEN MON 
NIGHT AND TUE WITH WINDS CLOCKING TO THE NW ACROSS THE NORTHERN
WATERS TUE NIGHT AND GRADUALLY INCREASING TO 15 TO 20 KT BY
MIDNIGHT...AND 20 TO 25 KT AROUND SUNRISE WED WITH THESE CONDITIONS
SPREADING S ACROSS THE GULF WATERS N OF 25N BY SUNSET WED. NW WINDS
AT 10 TO 15 KT ARE EXPECTED ON THU...WITH VARIABLE WINDS AT 5 TO
10 KT BY EARLY FRI...THEN BECOMING SOUTHERLY AND INCREASING TO 10
TO 15 KT FRI NIGHT.

A SURFACE HIGH PRESSURE IS ANALYZED NEAR 31N142W WITH A RIDGE SE 
15N101W. THE GRADIENT E OF THE RIDGE IS SUPPORTING NW WINDS AT 20
TO 25 KT ACROSS THE PACIFIC WATERS N OF 27N E OF 120W WITH SEAS
9 TO 11 FT IN NW SWELL. THE AREA OF ENHANCED WINDS AND SEAS WILL
SPREAD FURTHER W TO ALONG 122W ON MON AND ALONG 125W ON TUE AS
LONG PERIOD NW SWELL BUILDS SEAS 9 TO 16 FT...WITH SEAS TO 12 FT
REACHING THE NORTHERN BAJA PENINSULA BRIEFLY ON TUE. NE TRADES
SW THE RIDGE ARE AT 20 TO 25 KT ACROSS THE WATERS FROM 07N TO 20N
W OF 130W...BUT ARE EXPECTED TO DIMINISH ON WED. 

$$
NELSON