000
AXPZ20 KNHC 170946
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC WED APR 17 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0945 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS NW FROM THE COAST OF COLOMBIA AT 
04N77W TO 09N86W TO 05N95W TO 07N114W TO 00N123W WHERE 
SCATTEROMETER WINDS SUGGEST A TRANSITION  TO AN ITCZ WHICH
CONTINUES SW ACROSS THE EQUATOR TO BEYOND 03S140W. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION IS OBSERVED WITHIN 30 NM
OF 02.5N79W. ISOLATED MODERATE TO STRONG CONVECTION IS NOTED 
ALONG THE MONSOON TROUGH FROM 02N TO 09N BETWEEN 98W AND
116W. 

...DISCUSSION... 
GULF OF CALIFORNIA...A TROUGH HAS MOVED INTO THE GULF WATERS
N OF 29N ACCOMPANIED BY NW WINDS AT 15 TO 20 KT TO THE N OF
THE BOUNDARY. SW TO W WINDS AT 5 TO 15 KT ARE OBSERVED S OF
THE TROUGH. AS THE TROUGH PASSES E OF THE AREA TODAY THE N
WINDS AT 15 TO 20 KT WILL SPREAD S REACHING ACROSS THE ENTIRE
GULF OF CALIFORNIA WATERS BY EARLY THIS EVENING...THEN 
INCREASE TO 20 TO 25 KT ON THU...EXCEPT 25 TO 30 KT ACROSS
THE CENTRAL WATERS. SEAS ARE EXPECTED TO BUILD TO A MAX OF 7 
TO 10 FT S OF THE AREAS OF LONGEST NW TO SE FETCH...ROUGHLY
NEAR ALONG 26N. THE GRADIENT WILL RELAX ON FRI NIGHT WITH THE
NORTHERLY FLOW DIMINISHING TO 15 TO 20 KT...THEN FURTHER
DIMINISHING TO 5 TO 10 KT ON SAT AS THE SEAS SUBSIDE TO 2 TO
3 FT. WINDS WILL BECOME LIGHT AND VARIABLE ACROSS THE ENTIRE
GULF OF CALIFORNIA ON SAT NIGHT...THEN BECOME SE AT 10 TO 15
KT ON SUN...AND SE AT 5 TO 10 KT ON MON.
 
GULF OF TEHUANTEPEC...SOUTHERLY WINDS AT 5 TO 15 KT ARE
EXPECTED ACROSS THE GULF OF TEHUANTEPEC...AND JUST TO THE S OF 
THE GULF THROUGH LATE FRI AFTERNOON. NORTHERLY WINDS WILL SURGE
THROUGH THE CHEVILA PASS ON FRI EVENING INITIALLY AT 15 TO 20
KT...BUT QUICKLY INCREASE TO 20 TO 30 KT LATE FRI NIGHT AND 
CONTINUE THROUGH SUNRISE SAT...WITH SEAS BUILDING TO A MAX OF 11
FT NEAR 15N95W. THE N WINDS WILL DIMINISH TO 20 TO 25 KT BY SAT
AFTERNOON WITH THE SOUTHERN EXTENT OF THESE N WINDS REACHING 
13N95W SAT EVENING. LITTLE CHANGE EXPECTED THROUGH SUNRISE SUN
THEN WINDS WILL QUICKLY DIMINISH TO 15 TO 20 KT BY MID MORNING
SUN...AND 10 TO 15 KT BY SUN EVENING. THE RESULTANT N SWELL WILL
BUILD SEAS TO 8 FT...WITH THESE CONDITIONS PROPAGATING SW TO
NEAR 10N99W LATE SUN WHILE CONTINUING TO MIX WITH CROSS EQUATORIAL
S SWELL AND SUBSIDE BELOW 8 FT ON SUN NIGHT. 

GULF OF PAPAGAYO...ENE WINDS AT 15 TO 20 KT WILL CONTINUE THROUGH 
SUNRISE TODAY THEN DIMINISH TO 5 TO 10 KT THIS AFTERNOON. THE
PATTERN WILL REPEAT TONIGHT AND THU. THE GRADIENT IS EXPECTED
TO RELAX THU AFTERNOON THROUGH MON...WITH LIGHT AND VARIABLE WINDS
EXPECTED EACH AFTERNOON THROUGH LATE EVENING...WITH THE LATE NIGHT
THROUGH SUNRISE ENE DRAINAGE FLOW AT ONLY 10 TO 15 KT.

GULF OF PANAMA...LIGHT AND VARIABLE WINDS AT 5 TO 10 KT ARE
EXPECTED THROUGH SUN.

SURFACE HIGH PRESSURE IS ANALYZED NW OF THE AREA WITH A RIDGE 
AXIS EXTENDING SE INTO THE DISCUSSION AREA FROM 32N138W TO 
12N102W. THE GRADIENT NE OF THE RIDGE AXIS IS SUPPORTING N 
WINDS AT 15 TO 20 KT ACROSS THE WATERS N OF 25N BETWEEN 116W
AND 133W...WITH LONG PERIOD N SWELL RESULTING IN COMBINED SEAS
OF 7 TO 11 IN MIXED N SWELL. NE WINDS CONTINUE AT 15 TO 20 KT 
ACROSS THE TROPICAL WATERS SW OF THE RIDGE...GENERALLY W OF 
125W...AND NE AT 10 TO 15 KT BETWEEN 105W AND 125W. THE 
AFFECTED AREA NE OF THE RIDGE WILL GRADUALLY SHRINK TONIGHT
AND THU WITH SEAS SUBSIDING BELOW 8 FT. THE NE TRADES SW OF
THE RIDGE WILL CONTINUE RESULTING IN SEAS BUILDING 7 TO 8 FT
ACROSS THE WATERS FROM 10N TO 18N W OF 122W ON FRI. THE
GRADIENT SW OF THE RIDGE WILL RELAX OVER THE WEEKEND WITH SEAS
SUBSIDING TO 6 TO 7 FT. 

W TO NW WINDS AT 15 TO 20 KT...WITH SEAS 5 TO 8 FT IN NW 
SWELL...ARE CURRENTLY OBSERVED ALONG THE W COAST OF THE BAJA
CALIFORNIA PENINSULA TO THE N OF 26N WHILE 10 TO 15 KT WINDS
ARE OBSERVED S OF 26N WITH SEAS OF 4 TO 6 FT. EXPECT THE
GRADIENT TO TIGHTEN A LITTLE TODAY WITH NW WINDS AT 15 TO 20
KT SPREADING S ACROSS THE PACIFIC WATERS ALONG THE ENTIRE
PENINSULA. THE GRADIENT WILL RELAX ON THU AND FRI AS THE
WINDS CLOCK TO ALMOST DUE N AT 10 TO 15 KT...WITH SEAS
SUBSIDING TO 4 TO 5 FT. NW WINDS AT 5 TO 15 KT ARE EXPECTED
ALONG THE ENTIRE PENINSULA ON SAT THROUGH MON WITH SEAS 3 TO
5 FT IN MIXED NW AND S SWELL.
  
$$
NELSON