000
AXPZ20 KNHC 270338
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED MAR 27 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0315 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 
THE MONSOON TROUGH EXTENDS W FROM THE COAST OF COLOMBIA AT 08N78W TO
04N85W. THE ITCZ FORMS AT 01N109W AND WIGGLES W TO BEYOND 01N140W.
SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED IN CLUSTERS
WITHIN 120 NM OF 05.5N85W...05N93W...05.5N115.5W AND 02N132W.

...DISCUSSION...

GULF OF TEHUANTEPEC...A N TO S ORIENTATED SURFACE RIDGE EXTENDS 
FROM S TEXAS TO THE WESTERN BAY OF CAMPECHE WITH N WINDS SURGING
THROUGH THE CHIVELA PASS INTO AND DOWNSTREAM OF THE GULF OF
TEHUANTEPEC AT 30 TO 40 KT...WITH MAXIMUM SEAS OF 17 FT NEAR 14N96W.
THE GRADIENT WILL BEGIN TO RELAX AFTER SUNRISE ON WED WITH WINDS
DIMINISHING TO A MINIMAL GALE WHICH WILL PERSIST THROUGH SUNRISE THU
THEN QUICKLY DIMINISH TO 20 TO 25 KT THU AFTERNOON. ALTHOUGH THE 
NORTHERLY WINDS WILL FURTHER DIMINISH TO 10 TO 15 KT THU EVENING...
EXPECT ANOTHER N SURGE TO 20 TO 25 KT LATE THU NIGHT CONTINUING
THROUGH SUNRISE FRI. ONE LAST NORTHERLY SURGE...BUT AT ONLY 10 TO
15 KT IS EXPECTED LATE FRI NIGHT INTO MID MORNING ON SAT.  
  
GULF OF PAPAGAYO...ENE WINDS ARE CURRENTLY INCREASING TO 20 TO 25 KT
IN AND JUST DOWNSTREAM OF THE GULF OF PAPAGAYO...WITH THESE CONDITIONS 
EXTENDING AS FAR W AS 10N88W. THE TIGHT GRADIENT WILL CONTINUE THESE
CONDITIONS WITH THE WESTERN EXTENT NEAR 09N92W ON WED AND NEAR 08N93W
ON THU AS SEAS GRADUALLY BUILD TO 10 FT. LITTLE CHANGE EXPECTED THROUGH
THE WEEKEND.

GULF OF PANAMA...NORTHERLY WINDS WILL INCREASE TO 15 TO 20 KT LATE
TONIGHT AND CONTINUE THROUGH LATE FRI.

THE LARGE SWELLS GENERATED IN AND DOWNSTREAM OF THE GULFS OF TEHUANTEPEC
AND PAPAGAYO WILL MERGE COVERING THE TROPICAL WATERS FROM 03N TO 11N 
BETWEEN 93W AND 110W ON THU WITH COMBINED SEAS OF 7 TO 10 FT. THE AFFECTED
AREA WILL SHIFT W COVERING THE WATERS FROM 03N TO 10N BETWEEN 88W AND 117W
BY LATE FRI.

THE UPPER FLOW IS ZONAL ACROSS THE DISCUSSION AREA N OF 10N BETWEEN 110W
AND 140W AND IS ADVECTING UPPER MOISTURE ACROSS THE AREA FROM 15N TO 32N
BETWEEN 115W AND 123W. OTHERWISE THE UPPER LEVELS APPEAR DRY ACROSS THE
SUBTROPICS...N OF 23N. ANOTHER MOISTURE PLUME IS STREAMING W IN THE UPPER
ZONAL FLOW ACROSS THE AREA FROM 17N TO 21N BETWEEN 115W AND 140W. AN UPPER
TROUGH IS NOTED S OF 10N ALONG 118W...AND IS EFFECTIVELY SEPARATING THE 
UPPER FLOW OVER THE DEEP TROPICS. WEAK UPPER DIFFLUENCE HAS SOMEWHAT
SUPPORTED THE CLUSTERS OF CONVECTION PREVIOUSLY MENTIONED...WITH THE
RESULTANT UPPER MOISTURE ADVECTED NE FROM THE EQUATOR TO 12N BETWEEN 101W
AND 116W. A BROAD UPPER RIDGE DOMINATES THE TROPICS E OF 102W...WITH THE
UPPER RIDGE AXIS ROUGHLY IN PHASE WITH THE PREVIOUSLY DESCRIBED LOWER
LEVEL AXIS OF THE MONSOON TROUGH AND ITCZ...WITH ISOLATED CONVECTIVE
CLUSTERS FLARING ALONG 06N BETWEEN THE COLOMBIAN COAST AND 95W. 

A BROAD SURFACE RIDGE DOMINATES THE NW PORTION OF THE DISCUSSION AREA WITH
HIGH PRESSURE CENTERS ANALYZED AT 26N139W AND 30N126W. THE HIGHS WILL MERGE
AND SHIFT EAST ALLOWING A WEAK COLD FRONT OVER THE NW WATERS TO ADVANCE E...
BUT ONLY BE ACCOMPANIED BY A SW TO W AND TO NW WIND SHIFT. A SECOND STRONGER
COLD FRONT WILL REACH 32N140W ON THU AFTERNOON...AND EXTEND FROM 32N133W
TO 26N135W ON FRI AFTERNOON. THIS FRONT WILL BE ACCOMPANIED BY W TO NW 20
TO 25 KT WINDS AND LARGE SWELLS WHICH WILL DRIVE UP THE COMBINED SEAS TO 8
TO 13 FT OVER THE NW WATERS ON FRI.
 
$$
NELSON