000
AXPZ20 KNHC 160344
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE JUN 16 2009

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0315 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS ALONG THE LINE...08N82W TO 
09N105W TO 07N115W TO 07N140W. SCATTERED MODERATE/ISOLATED STRONG
CONVECTION EXISTS FROM 8N-13N BETWEEN 103W-109W. SCATTERED 
MODERATE CONVECTION IS WITHIN 60 NM OF THE AXIS BETWEEN 95W-100W.

...DISCUSSION...

WELL DEFINED DEEP LAYER TROUGH FROM SOUTHERN CALIFORNIA AND OVER 
THE PACIFIC OCEAN OFFSHORE FOR ABOUT 600 NM EXTENDS TO THE 
SOUTHWEST ACROSS THE AREA TO THE ITCZ WEST OF 130W. A WEAKENING 
PLUME OF UPPER LEVEL MOISTURE EMANATING FROM THE ITCZ IS 
ASSOCIATED WITH THE SOUTHERLY FLOW EAST OF THE TROUGH AXIS AND 
EXTENDS EAST OF A LINE FROM NEAR 31N100W TO 22N120W TO 10N133W. 
WEST OF THIS LINE THE ATMOSPHERE IS MOSTLY DRY AND CLOUD FREE IN 
THE MIDDLE AND UPPER LEVELS WITH PATCHY STRATOCUMULUS IN THE 
LOWER LEVELS. THE EXCEPTION IS ASSOCIATED WITH A STRONG 
SHORTWAVE DROPPING INTO THE TROUGH FROM THE NORTHWEST WITH MULTI 
LEVEL BROKEN TO OVERCAST CLOUDS NORTH OF 30N FROM 117W TO 127W 
AND A SMALL AREA OF HIGH CLOUDS WITHIN 75 NM EITHER SIDE OF A 
LINE FROM 32N118W TO 28N125W. EVEN THE MOISTURE PLUME ON THE 
EAST FLANK OF THE TROUGH IS CLOUD FREE IN THE MIDDLE AND UPPER 
LEVELS. THE TROUGH IS FORECAST TO REMAIN IN PLACE AND STRENGTHEN 
THROUGH MID WEEK AND TO BECOME A CUT-OFF LOW WEST OF BAJA 
CALIFORNIA LATER IN THE WEEK.

ANOTHER DEEP LAYER TROUGH IS OVER THE SOUTHERN GULF OF MEXICO 
AND EASTERN MEXICO AND EXTENDS SOUTHWESTWARD OVER THE PACIFIC 
WITH A TROUGH AXIS FROM NEAR 22N90W TO THE ITCZ NEAR 100W. THE 
TROUGH IS MOVING WEST ABOUT 12 KNOTS AND IS FORECAST TO ONLY 
WEAKEN SLIGHTLY THROUGH MID WEEK THEN WEAKEN FURTHER. ASSOCIATED 
WITH THE TROUGH IS AN ACTIVE AREA OF CONVECTION WITH SCATTERED 
MODERATE WITH ISOLATED STRONG CONVECTION WITHIN 90 NM OF THE 
POINT 12N105.5W. A BROAD AREA OF MULTI LEVEL CLOUDS IS OVER THE 
PACIFIC AREA EAST OF THE TROUGH WITHIN A BROAD AREA OF UPPER 
DIFFLUENCE.

REMAINDER OF THE MIDDLE AND UPPER LEVELS IS UNDER BROAD 
ANTICYCLONIC FLOW.

A WEAK SURFACE TROUGH IS ASSOCIATED WITH TROUGH OFF OF SOUTHERN 
CALIFORNIA AND IS ALONG A LINE THROUGH 32N120W TO 25N128W. 
ELSEWHERE NORTH OF 12N WEST OF 110W A WEAK SURFACE RIDGE IS 
ANALYZED. REMAINDER OF THE AREA IS ANALYZED AS A BROAD SURFACE 
TROUGH.
 
$$
LL