000
AXPZ20 KNHC 290954
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC FRI MAR 29 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 
0900 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
MONSOON TROUGH AXIS EXTENDS FROM 07N77W TO 05N87W THEN ITCZ
AXIS TO 03N110W TO 04N116W TO 02N131W TO 02N140W.  SCATTERED
MODERATE WITHIN 90 NM OF AXIS FROM 118W TO 130W.

...DISCUSSION...
DEEP LAYERED CYCLONE JUST N OF AREA AT 32N135W HAS TROUGH EXTEND
SW TO 20N147W ACROSS NW OF BASIN.  SYSTEM SUPPORTS COLD FRONT
CURRENTLY FROM 32N132W TO 26N140W.  STRONG NW WINDS AND SEAS TO
14 FT ARE ASSOCIATED WITH FRONT AS IT SHIFT NE LATER TODAY AND 
ALLOWS WINDS TO DIMINISH.  NW SWELLS LINGER AS FAR S AS 22N BY
EARLY SUN.  ONCE CYCLONE HAS SHIFTED NE...UPPER PATTERN BECOMES
QUITE TAME WITH BROAD RIDGE E OF 120W AND REMNANTS OF TROUGH
ALONG 135W.

ONE FLY IN THE OINTMENT IS ENORMOUS AMOUNT OF MOISTURE ADVECTED
ON 95 KT JET CORE SE OF TROUGH.  POSSIBILITY OF SHORT WAVE 
SLIDING UNDER CYCLONE AND USING ALL THAT MOISTURE TO GIVE WINTER
ONE MORE GASP.  

...ELSEWHERE AT THE LOWER LEVELS...
GULF OF TEHUANTEPEC...HIGH PRES CENTER OVER GULF OF MEXICO SHIFT
E VEERING WINDS OVER BAY OF CAMPECHE AND EFFECTIVELY CUTTING OFF
FLOW ACROSS CHIVELAS PASS INTO GULF OF TEHUANTEPEC. STRONG WINDS
DIMINISH TO FRESH FLOW LATE TODAY AND TO A MODERATE BREEZE SUN.
  
GULF OF PAPAGAYO...COLD FRONT ACROSS WESTERN CARIBBEAN THAT 
MAINTAINED TIGHT PRES GRADIENT AND STRONG WINDS CROSSING 
MOUNTAIN GAPS OVER NICARAGUA HAS BEGUN TO DISSIPATE.  WINDS OVER
GULF OF PAPAGAYO EXPECTED TO CONTINUE TODAY AND WEAKEN TONIGHT
AND SUN.  ALTHOUGH DOWNSLOPE DRAINAGE ON W SIDE OF MOUNTAIN
RANGE IS STILL CAPABLE OF PRODUCING FRESH OUTFLOW IN LATE NIGHTS
AND EARLY MORNING HOURS ACROSS REGION...SEAS SHOULD REMAIN BELOW
8 FT.  

GULF OF PANAMA...SIMILARLY TO GULF OF PAPAGAYO...FRESH N BREEZE
SEEPS ACROSS PANAMA BUT NOT ENOUGH BUILD SEAS ABOVE 7 FT.  WINDS
DIMINISH LATER TODAY AS CARIBBEAN WINDS DIE DOWN. 

LARGE SWELLS GENERATED BY GULFS OF TEHUANTEPEC AND PAPAGAYO
MERGED WELL DOWNSTREAM S OF 10N FROM 94W TO 130W...WITH COMBINED
SEAS TO 10 FT.  SUBSIDING SWELLS EXPECTED TO PROPAGATE W THROUGH
SUN.    

SURFACE HIGH PRES AT 26N116W WEAKENS BUT IS ABLE TO HOLD ITS 
GROUND AGAINST APPROACHING COLD FRONT ENTERING NW PORTION OF 
BASIN TODAY.  

...LOOKING AHEAD...
SECOND COLD FRONT ENTERS NW CORNER OF BASIN LATE WED BUT FOLLOWS
SAME FATE OF PREVIOUS FRONT...DEVIATE NE WITH ONLY SHORT-LIVED
INCREASE OF WINDS.  NEVERTHELESS...SEAS MAY ADD TO ALREADY HIGH
SWELL LINGERING FROM PREVIOUS FRONT. 

$$ WALLY BARNES