000
AXPZ20 KNHC 130947
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SAT APR 13 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 W FROM THE COLOMBIA AND PANAMA
BORDER ACROSS SOUTHERN PANAMA TO THE BORDER OF PANAMA AND
COSTA RICA AT 08N83W...THEN TURNS SW TO 05N91W...THEN W TO
08N118W. SCATTEROMETER WINDS INDICATE THE ITCZ FORMS AT
08N118W AND EXTENDS WSW TO BEYOND 03N140W. SMALL CLUSTERS OF
STRONG CONVECTION IS FLARING S OF THE MONSOON TROUGH WITHIN
120 NM EITHER SIDE OF A LINE FROM 06N82W TO 04N105W. SCATTERED
MODERATE ISOLATED STRONG CONVECTION IS OBSERVED WITHIN 60 NM
EITHER SIDE OF A LINE FROM 10N110W TO 09.5N120.5W...AND WITHIN
30 NM OF 05N121W.

...DISCUSSION... 
GULF OF CALIFORNIA...SOUTHERLY 5 TO 10 KT WINDS ARE EXPECTED
ACROSS THE GULF OF CALIFORNIA WATERS THIS MORNING WITH THE
SOUTHERLY FLOW EXPECTED TO INCREASE TO 10 TO 15 KT ACROSS THE
WATERS N OF 28N THIS AFTERNOON AND TONIGHT...THEN INCREASE TO
15 TO 20 KT AROUND SUNRISE ON SUN WITH THESE CONDITIONS
CONTINUING THROUGH LATE MON NIGHT. WINDS WILL CLOCK TO NNW 
ACROSS THE GULF WATERS N OF 28N ON TUE NIGHT AND INCREASE TO 20
TO 25 KT...WITH NW WINDS AT 15 TO 25 KT SPREADING S ACROSS THE
ENTIRE GULF OF CALIFORNIA ON WED. THE NW WINDS WILL DIMINISH TO
15 TO 20 KT ON THU. SEAS ARE EXPECTED TO BUILD TO 7 FT IN AREAS
OF LONG N TO S FETCH ACROSS THE CENTRAL GULF WATERS WED NIGHT
INTO THU MORNING.

GULF OF TEHUANTEPEC...LIGHT AND VARIABLE WINDS SOUTHERLY WINDS
ARE EXPECTED ACROSS THE GULF OF TEHUANTEPEC THROUGH THU.

GULF OF PAPAGAYO...ENE WINDS ARE EXPECTED AT 10 TO 15 KT LATE
EACH NIGHT TILL JUST AFTER SUNRISE EACH MORNING THROUGH MON
NIGHT. INCREASING GRADIENT ACROSS THE CARIBBEAN WILL RESULT
IN ENE 15 TO 20 KT WINDS ACROSS THE GULF OF PAPAGAYO AT 
SUNRISE ON BOTH TUE AND WED WITH SEAS BUILDING TO 7 FT. 
GUIDANCE SUGGESTS THE GRADIENT WILL RELAX SUPPORTING NE TO E
WINDS AT 10 TO 15 KT AROUND SUNRISE ON THU.  

GULF OF PANAMA...NORTHERLY WINDS AT 5 TO 10 KT ARE EXPECTED
TO INCREASE TO 10 TO 15 KT TONIGHT. THE GRADIENT IS EXPECTED
TO RELAX ON SUN SUPPORTING LIGHT AND VARIABLE WINDS AT 5 TO
10 KT THROUGH THU.

SURFACE HIGH PRESSURE IS ANALYZED NW OF THE AREA WITH A RIDGE 
AXIS EXTENDING SE INTO THE DISCUSSION AREA FROM 32N136W TO 
19N114W. THE GRADIENT NE OF THE RIDGE AXIS IS SUPPORTING N 
WINDS AT 15 TO 20 KT ACROSS THE WATERS N OF 25N BETWEEN 115W
AND 132W...WITH COMBINED SEAS OF 8 TO 11 FT IN N SWELL. NE TO
E WINDS ARE OBSERVED SW OF THE RIDGE ACROSS THE WATERS FROM 
16N TO 25N BETWEEN 135W AND 140W...WITH SEAS TO 8 FT. THE AREA 
OF WINDS TO THE NE OF THE RIDGE WILL SHIFT WESTWARD AFFECTING
THE WATERS N OF 27N BETWEEN 122W AND 132W ON SUN AS SEAS
SUBSIDE TO 8 FT. A SECONDARY SURGE OF LONG PERIOD N SWELLS WILL
ARRIVE ON SUN AFTERNOON DRIVING THE COMBINED SEAS UP TO 11 FT
ON SUN EVENING ACROSS THE WATERS N OF 27N BETWEEN 118W AND 130W.
THESE SWELLS WILL CONTINUE S REACHING ALONG 23N MON NIGHT THEN
BEGIN TO GRADUALLY SUBSIDE THROUGH MID WEEK. 

$$
NELSON