000
AXPZ20 KNHC 180948
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC FRI FEB 18 2011

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...ITCZ...
AXIS EXTENDS FROM 00N111W TO 07N132W TO 06N140W. SCATTERED 
MODERATE CONVECTION WAS NOTED WITHIN 60 NM N OF AXIS W OF 129W.

...DISCUSSION...
RELATIVELY QUIET CONDITIONS OVER THE NE PACIFIC THIS MORNING 
WITH NO GALES CURRENTLY PRESENT AND NONE ANTICIPATED OVER THE 
NEXT FEW DAYS.
  
A NEW COLD FRONT HAS ENTERED NORTHERN PORTIONS OVERNIGHT... 
LOCATED FROM 30N127W TO 26N138W. SURFACE WINDS ARE FORECAST TO 
PEAK AT 20 TO 25 KT FROM THE S TO SW WINDS AHEAD OF THE FRONT 
AND NW TO N WINDS BEHIND IT DURING THE NEXT TWO DAYS AS THE 
FRONT SHIFTS E INTO SOUTHERN CALIFORNIA AND N PORTIONS OF BAJA 
CALIFORNIA. AS THE FRONT APPROACHES BAJA TONIGHT FRESH SWLY 
WINDS ARE EXPECTED IN THE N GULF OF CALIFORNIA. NW SWELL 
ASSOCIATED WITH THIS CURRENT COOL AIR OUTBREAK IS REINFORCING 
THE PRE-EXISTING NW SWELL OVER MUCH OF THE AREA.  PEAK 
SIGNIFICANT WAVE HEIGHTS ARE REACHING 14 TO 16 FT N OF 25N W OF 
120W.  THESE WILL DIMINISH SOME BY SATURDAY NIGHT...BUT STILL 
REMAIN OVER 12 FT FOR MOST OF THE AREA N OF 20N. A VERY SMALL 
AREA OF FRESH TRADEWINDS REMAINS CONFINED NEAR 10N W OF 135W.  
WHILE THE PRESSURE GRADIENT REMAINS MODEST...FRESH TRADE WINDS 
WILL CONTINUE ACROSS THIS AREA WITH LITTLE CHANGE THROUGH 
SATURDAY NIGHT. E OF 110W...WINDS REMAIN LIGHT TO MODERATE 
ACROSS THE AREA WITH ONLY GAP WINDS REACHING NEAR 20 KT. 

IN THE UPPER LEVELS...A HIGH AMPLITUDE TROUGH IS SEEN IN THE 
WATER VAPOR IMAGERY ALONG 24N125W TO 06N142W. RIDING ALONG THE 
WESTERN FLANK OF THIS TROUGH IS A VIGOROUS SHORT-WAVE TROUGH 
THAT HAS SWEPT SE INTO THE DISCUSSION AREA FROM 30N131W TO 
25N133W.  THIS SHORT-WAVE TROUGH IS PROVIDING UPPER LEVEL 
SUPPORT FOR THE COLD FRONT.  EAST OF 110W SOUTH OF 20N...ZONAL 
WESTERLY FLOW PREVAILS ALOFT.

GAP WINDS...
A 0328 UTC ASCAT PASS SHOWS THE PAPAGAYO GAP WIND EVENT WEST OF 
NICARAGUA CONTINUING TO PRODUCE NE TO E WINDS OF 20 TO 25 KT.  
THESE WINDS SHOULD CONTINUE DUE TO TRADEWIND FORCING FROM THE 
CARIBBEAN SEA THROUGH THE NEXT TWO DAYS...WITH HIGHEST WINDS AND 
SEAS IN LATE NIGHT AND MORNING HOURS AND LOWER WINDS AND SEAS IN 
THE AFTERNOON AND EARLY EVENING.

A GULF OF TEHAUNTEPEC WIND EVENT SHOULD BEGIN LATE FRIDAY NIGHT 
WITH FORCING DUE TO A NE WIND SURGE ACROSS NORTHERN CENTRAL 
AMERICA.  THIS WILL LIKELY LAST THROUGH LATE SUNDAY...BUT SHOULD 
STAY JUST BELOW GALE FORCE CONDITIONS.

$$
STRIPLING