000
AXPZ20 KNHC 060312
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SUN MAY 06 2012

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 
0230 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE MONSOON TROUGH IS ALONG 08N78W TO 11N86W TO 06N104W TO 
08N112W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 
04N117W TO 04N131W TO 03N140W. SCATTERED MODERATE AND ISOLATED 
STRONG CONVECTION IS FROM 04N TO 09N BETWEEN 84W AND 89W. 
SIMILAR CONVECTION IS N OF THE MONSOON TROUGH TO 12N BETWEEN 95W 
AND 100W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM S OF 
THE MONSOON TROUGH BETWEEN 104W AND 111W. SIMILAR CONVECTION IS 
WITHIN 90 NM EITHER SIDE OF A LINE FROM 02N127W TO 06N132W.

...DISCUSSION...

ALOFT...N OF 25N...A VERY BROAD OMEGA BLOCKING PATTERN STRADDLES 
BOTH SIDES OF N AMERICA...CENTERED ON AN UPPER LEVEL RIDGE ALONG 
ABOUT 98W. SOUTHERN STREAM IMPULSES CONTINUE TO MOVE SLOWLY 
UNDERNEATH THE RIDGE...THE WESTERN-MOST BEING A NEGATIVELY 
TILTED MIDDLE TO UPPER TROUGH EXTENDING FROM THE SE CORNER OF 
ARIZONA TO ALONG THE SPINE OF CENTRAL OLD MEXICO. MULTI-LAYERED 
MID TO UPPER LEVEL CLOUDINESS ASSOCIATED WITH THIS FEATURE 
CONTINUES TO GRADUALLY SHIFT NE FROM THE W COAST OF MEXICO TO 
THE GULF COAST OF MEXICO. TO THE W OF THIS FEATURE...A BROAD 
UPPER LEVEL TROUGH IS CENTERED ACROSS W COASTAL PORTIONS OF N 
AMERICA N OF 25N...WHILE A BROAD AND RELATIVELY FLAT UPPER LEVEL 
RIDGE COVERS MUCH OF THE DISCUSSION AREA FROM 11N-24N W OF 111W.

AT THE LOWER LEVELS...1036 MB HIGH PRES WELL NW OF THE 
DISCUSSION WATERS NEAR 39N135W EXTENDS A RIDGE INTO THE AREA 
NEAR 32N130W CONTINUING SE TO NEAR 17N112W. A DRY FRONTAL ZONE 
WITH REINFORCING COOL AND DRY AIR ENTERED THE NW PORTION OF THE 
AREA DURING THE PAST 24 HOURS. THE PRES GRADIENT BEHIND THIS 
BOUNDARY HAS INDUCED A ZONE OF 20-25 KT N-NE WINDS N OF 20N W OF 
A LINE FROM 30N123W TO 25N123W TO 20N130W...AS INDICATED BY 
RECENT ASCAT AND OSCAT SCATTEROMETER PASSES. MEANWHILE A BELT OF 
FRESH NE TRADES PREVAILS S-SE OF THE RIDGE FROM 07N-11N BETWEEN 
128W AND 135W. 

A STRONG PRES GRADIENT ALONG THE CENTRAL AND SOUTHERN CALIFORNIA 
COAST IS GENERATING NW WINDS TO GALE FORCE...CREATING NW SWELL 
WHICH CONTINUES TO PROPAGATE INTO THE NE WATERS...WHERE SEAS 
WERE REACHING TO 11 FT ALONG 30N...AND UP TO 14 FT WELL OFFSHORE 
OF SAN DIEGO. THE HIGH WILL WEAKEN SLIGHTLY AND SHIFT SW THROUGH 
EARLY NEXT WEEK...WITH THE ASSOCIATED FRESH WINDS AND TRADES 
ALSO SHIFTING TO THE W AND SW.

1010 MB LOW PRES IS NEAR 06N115W WITH AN ATTENDANT TROUGH FROM 
11N113W TO THE LOW. SCATTERED MODERATE AND ISOLATED STRONG 
CONVECTION IS WITHIN 120-180 NM IN THE W QUADRANT OF THE LOW. 
THIS LOW AND TROUGH WILL DRIFT W DURING THE NEXT 24-48 HOURS 
WITH NO DEVELOPMENT ANTICIPATED.

LIGHT TO MODERATE MONSOONAL FLOW PREVAILS OVER THE SE PORTION OF 
THE AREA...GENERALLY E OF 112W...AND CONTINUES TO FORCE ACTIVE 
CONVECTION ACROSS THE AREA AS DESCRIBED ABOVE. THESE CONDITIONS 
ARE EXPECTED TO PREVAIL THROUGH THE WEEKEND INTO EARLY NEXT WEEK.

A PULSE OF VERY LONG PERIOD SOUTHERN HEMISPHERIC SWELL IS NOW 
PROPAGATING N OF THE EQUATOR COVERING THE WATERS S OF 03N 
BETWEEN 105W AND 120W. THIS SWELL WILL DECAY TO LESS THAN 8 FT 
IN 24-36 HOURS.

$$
LEWITSKY