000
AXPZ20 KNHC 141547
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC FRI MAR 14 2008

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1545 UTC.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 1S81W 4N95W CROSSES EQUATOR AT 103W 
8N119W 6N140W. SCATTERED MODERATE ISOLATED STRONG WITHIN 120 NM 
EITHER SIDE OF 8N BETWEEN 119W AND 125W. SCATTERED MODERATE 
ISOLATED STRONG WITHIN 60NM EITHER SIDE OF 7.5N BETWEEN 131W AND 
134W. SCATTERED MODERATE FROM 9N TO 10N BETWEEN 105W AND 106W.

...DISCUSSION...
A FLAT...MID- TO UPPER-LEVEL RIDGE CENTERED NEAR 23N123W THIS 
MORNING SHOULD ABRUPTLY BREAK DOWN LATER TODAY...AS STRONG 
HEIGHT FALLS ARRIVING FROM THE NORTH INTRODUCE A POTENT NORTHERN 
STREAM SHORTWAVE TO THE WEST COAST SATURDAY. IN RESPONSE...A 
STRONG COLD FRONT SHOULD DROP SOUTHWARD OFF THE CALIFORNIA COAST 
...LYING FROM 33N117W TO 30N122W TO 32N129W SATURDAY MORNING.  
AS THE SHORTWAVE AMPLIFIES FURTHER AND EVENTUALLY CLOSES OFF 
OVER THE DESERT SW...THE ASSOCIATED COLD FRONT SHOULD PRESS 
FARTHER SEWD...REACHING FROM 32N111W TO 24N112W TO 21N119W BY 
SUNDAY EVENING. IN THE WAKE OF THE FRONT...A STRONG 20- TO 30-KT 
NW TO N FLOW SHOULD EXPAND SOUTHWARD OFF THE CALIFORNIA AND BAJA 
CALIFORNIA COAST SATURDAY THROUGH MONDAY...CAUSING WAVE HEIGHTS 
TO RAPIDLY BUILD TO 10 TO 16 FT IN LONG PERIOD NW TO N SWELL 
SUNDAY MORNING AND THEN PEAK AT 11 TO 18 FT EARLY MON NORTH OF 
20N AND EAST OF 128W SUNDAY MORNING. BY MONDAY AND TUESDAY...THE 
COLD FRONT WILL HAVE PASSED THROUGH THE REMAINDER OF THE BAJA 
PENINSULA AS WELL AS MUCH OF NW AND NORTH CENTRAL MEXICO...WITH 
THE STRONG NW TO N FLOW AND WAVE HEIGHTS GRADUALLY DIMINISHING.

THE DEEPENING LONGWAVE TROUGH OVER THE FAR WEST THIS WEEKEND 
WILL LARGELY BE RELATED TO RIDGE AMPLIFICATION FORECAST TO OCCUR 
ALONG 150W STARTING TODAY. AS THIS OCCURS...A 1035MB SURFACE 
RIDGE IS FORECAST TO BUILD NEAR 39N146W BY THIS EVENING AND 
GRADUALLY SETTLE FARTHER SOUTHEAST NEAR 37N138W BY SUNDAY 
MORNING.  TO THE SOUTH OF THE SURFACE RIDGE...A TIGHTENING 
PRESSURE GRADIENT IS ALREADY EVIDENT OVER A LARGE EXPANSE OF THE 
SUBTROPICAL AND TROPICAL EASTERN NORTH PACIFIC WEST OF ABOUT 
130W THIS MORNING.  THIS AREA IS CHARACTERIZED BY WAVE HEIGHTS 
OF 8 TO 12 FT IN MIXED OLD NW SWELL PROPAGATING AWAY FROM THE 
FAR NORTH PACIFIC AN NEWLY-FORMED WIND-WAVE SWELL. MODELS 
SUGGEST THAT AS THE SURFACE RIDGE MATURES AND DRIFTS SE...AN 
EVEN LARGER AREA OF NE TO E 20- TO 25-KT WINDS SHOULD COVER AN 
AREA NORTH OF 9N AND WEST OF 125W....WITH WAVE FURTHER BUILDING 
TO 9 TO 13 FT IN A COMBINATION OF NEWLY-GENERATED SHORT PERIOD 
NE SWELL AND LONG PERIOD N SWELL PROPAGATING OUT OF THE GULF OF 
ALASKA AND THE AREA OFFSHORE THE CONUS WEST COAST.

OTHERWISE...A FAIRLY LIGHT WIND REGIME PERSISTS EAST OF 110W... 
WITH NO GAP WINDS OBSERVED IN EITHER THE GULF OF PAPAGAYO NOR 
THE GULF OF TEHUANTEPEC. WAVE HEIGHTS GENERALLY RANGE FROM 4 TO 
6 FT MOSTLY IN LONG PERIOD SW SWELL PROPAGATING OUT OF THE 
SOUTHERN HEMISPHERE.

$$
KIMBERLAIN