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Eastern Pacific Tropical Weather Discussion (Text)

000
AXPZ20 KNHC 250912
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC FRI APR 25 2014

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 
0830 UTC. 

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
A MONSOONAL CIRCULATION IS STILL NOT YET PRESENT ACROSS THE 
REGION...ALTHOUGH RECENT SCATTEROMETER DATA HAS BEGUN TO SHOW 
VERY WEAK S TO W WINDS S OF THE ITCZ E OF 100W. THE ITCZ AXIS 
EXTENDS FROM COLOMBIA NEAR 09N76W TO 09N87W TO 04N127W TO BEYOND 
03.5N140W. SCATTERED STRONG CONVECTION NOTED OVER SE PORTIONS OF 
GULF OF PANAMA FROM 08.5N79W EAST AND SOUTHEASTWARD INTO 
COLOMBIA. ISOLATED TO SCATTERED MODERATE ISOLATED STRONG 
CONVECTION NOTED WITHIN 120 NM N AND 210 NM S OF ITCZ BETWEEN 
84W AND 105W. 

...DISCUSSION...                                       
ALOFT...NEARLY ZONAL FLOW COVERS MUCH OF THE AREA N OF 10N W OF 
110W. AN UPPER LEVEL TROUGH IS SWEEPING ACROSS N PORTIONS OF THE 
AREA...EXTENDING FROM A CYCLONIC VORTEX MOVING SLOWLY E ACROSS 
THE FAR NE PACIFIC...SOUTHWARD TO NEAR 34N127W THEN SW TO 
24N144W THEN CONTINUING W AS A WEAK TUTT AXIS.  A WEAK SHORTWAVE 
RIDGE IS LOCATED JUST E OF THIS TROUGH AND N OF 20N...AND IS 
APPROACHING BAJA CALIFORNIA. OVERNIGHT...A MIDDLE TO UPPER LEVEL 
CYCLONIC VORTEX E OF THIS RIDGE HAS SHIFTED NE ACROSS THE S TIP 
OF BAJA CALIFORNIA AND INTO THE SINALOA REGION OF MEXICO. 
SUFFICIENT LOW AND MID LEVEL MOISTURE WAS PRESENT TO GENERATE 
SCATTERED MODERATE TSTORMS EXTENDING FROM NEAR 20N112W 
NORTHEASTWARD ACROSS SINALOA AND NAYARIT STATES. THIS CONVECTION 
HAS SINCE MOVED INLAND AND NEARLY ENDED. SOUTHEAST OF THIS UPPER 
FEATURE...AN UPPER RIDGE RESIDES BETWEEN 90W AND 110W...WHILE 
THE WEAKENING TAIL OF AN UPPER TROUGH EXTENDS SW ACROSS CENTRAL 
AMERICA TO NEAR 10N90W. 

AT THE SURFACE...THE UPPER TROUGH ACROSS THE NE PACIFIC IS 
SUPPORTING A COLD FRONT APPROACHING NW PORTIONS THIS 
MORNING...EXTENDING FROM NORTHERN CALIFORNIA TO NEAR 30N142W. 
HIGH PRES TO THE S OF THIS FRONT HAS COLLAPSED...WHILE A 1030 MB 
HIGH WAS BEHIND THE FRONT NEAR 35N150W AND BRIDGING ACROSS THE 
FRONT TO NEAR 23N114W. THE PRESSURE GRADIENT BETWEEN THE RIDGE 
AND LOWER PRESSURE ASSOCIATED WITH THE ITCZ IS SUPPORTING FRESH 
TRADES OVER THE WESTERN WATERS FROM 09N TO 19N W OF 120W WITH 
SEAS THERE RUNNING 8 TO 9 FT IN MIXED SWELL. THESE CONDITIONS 
WILL GENERALLY PREVAIL ACROSS THIS AREA THROUGH THE WEEKEND. THE 
REMNANTS OF THE COLLAPSED HIGH SE OF THE FRONT AND THE CURRENT 
RIDGE ARE PRODUCING GRADIENT INDUCED NW WINDS 20-25 KT OFF THE 
COAST OF SOUTHERN CALIFORNIA...WITH 15-20 KT NW WINDS EXTENDING 
S AND SE TO CENTRAL PORTIONS OF BAJA CALIFORNIA. RECENT 
ALTIMETER PASSES SHOW SEAS ACROSS THIS REGION RUNNING 8-10 FT IN 
PREDOMINANTLY NW SWELL. THIS FRONTAL SYSTEM IS FORECAST TO MOVE 
SE AND INTO N PORTIONS OF BAJA CALIFORNIA LATE TONIGHT THROUGH 
EARLY SATURDAY...BRINGING NW TO W WINDS 20-25 KT INTO THE OUTER 
WATERS N OF 28N AND ACROSS INTERIOR WATERS OF GULF OF CALIFORNIA 
N OF 29N DURING SAT AFTERNOON. THE FRONTAL SYSTEM WILL LIFT OUT 
AND INTO TEXAS THROUGH SUNDAY WITH WINDS AND SEAS GRADUALLY 
DIMINISHING ACROSS THE GULF OF CALIFORNIA...BUT NW WINDS 20-25 
KT ARE EXPECTED TO PERSIST ACROSS THE OUTSIDE WATERS N OF 25N 
THROUGH MON.

A VERY SIGNIFICANT SOUTHERN HEMI S SWELL IS MOVING THROUGH THE 
REGIONAL WATERS THIS MORNING. GLOBAL WAVE MODELS FORECAST THIS 
SWELL TO BEGIN REACHING THE PACIFIC COASTS FROM ECUADOR TO BAJA 
CALIFORNIA ANY MOMENT AND PEAK LATE TONIGHT THROUGH SUNDAY AT 6 
TO 8 FT. THIS VERY LONG PERIOD SWELL AT THAT SIZE WILL PRODUCE 
VERY LARGE AND POWERFUL SURF ALONG THE PACIFIC COASTS AND 
REEFLINES STARTING THIS AFTERNOON THROUGH SUNDAY. VERY DANGEROUS 
SURF CONDITIONS...STRONG AND WIDESPREAD RIP CURRENTS...AND 
COASTAL EROSION SHOULD BE EXPECTED THROUGH THE WEEKEND WITH THIS 
EVENT. 

OTHERWISE...EXPECT FAIRLY TRANQUIL WIND CONDITIONS ACROSS THE 
GULFS OF TEHUANTEPEC...PAPAGAYO...AND PANAMA THROUGH THE NEXT 
FEW DAYS...AS LIGHT TO MODERATE WINDS PREVAIL E OF 100W...AND 
THE EASTERN PACIFIC MONSOONAL CIRCULATION BEGINS TO BECOME 
ESTABLISHED DURING THE UPCOMING WEEK. 

$$ 
STRIPLING