000
AXPZ20 KNHC 101516
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC TUE MAR 10 2009

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 
1500 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS ALONG THE LINE...04N77W TO 
03N95W TO 01N105W TO 02N140W. THERE IS NO SIGNIFICANT CONVECTION 
ALONG THE ITCZ.

...DISCUSSION...

DEEP LAYER TROUGH IS OVER MOST OF THE PACIFIC OCEAN AREA NORTH 
OF 10N WEST OF A LINE FROM CENTRAL TEXAS TO 10N110W. THIS 
FEATURE WILL WEAKEN SLOWLY AND GIVE WAY TO SOUTHWESTERLY FLOW BY 
WEDNESDAY WITH A SHORTWAVE NORTH OF 30N JUST WEST OF CALIFORNIA. 
ASSOCIATED WITH THE TROUGH IS A PLUME OF MIDDLE AND UPPER LEVEL 
MOISTURE WITH BROKEN TO OVERCAST MULTI LEVEL CLOUDS WITH SOME 
EMBEDDED RAIN AND A FEW ISOLATED CONVECTIVE CELLS WITHIN ABOUT 
350 NM EITHER SIDE OF A LINE FROM 15N111W TO BEYOND 32N100W. 
THIS MOISTURE IS ADVECTING NORTHWARD ACROSS CENTRAL MEXICO. 
NORTH OF 22N WEST OF THIS MOISTURE PLUME TO 130W THE MIDDLE AND 
UPPER LEVELS ARE DRY AND CLOUD FREE. THE LOWER LEVELS IN THIS 
AREA ARE COVERED IN OVERCAST TO BROKEN STRATOCUMULUS CLOUDS 
WHICH EXTEND WEST TO BEYOND 140W.

ELSEWHERE BROAD RIDGE COVERS THE AREA IN THE MIDDLE AND UPPER 
LEVELS. EXCEPT FOR SOME ISOLATED CONVECTION NEAR THE ITCZ W OF 
135W THE AREA SOUTH AND EAST OF A LINE FROM 27N100W TO 15N105W 
TO 10N105W TO 14N140W IS DRY AND CLOUD FREE IN THE MIDDLE AND 
UPPER LEVELS. THIS AREA IS ALSO MOSTLY CLEAR IN THE LOWER 
LEVELS. 

MODERATE SURFACE RIDGE IS NORTH OF 10N W OF 102W. THIS FEATURE 
IS FORECAST TO CHANGE LITTLE THROUGH WEDNESDAY THEN WEAKEN SOME 
AS LOW PRESSURE DEVELOPS WEST OF 140W. ELSEWHERE A BROAD TROUGH 
IS ANALYZED AT THE SURFACE.

GAP NORTHEASTERLY WINDS IN AND DOWNSTREAM FROM THE GULF OF 
PAPAGAYO WILL CONTINUE FOR THE NEST SEVERAL DAYS IN THE 20 TO 25 
KNOT RANGE MOSTLY EAST OF 91W WITH OCCASIONAL 30 KNOTS WINDS 
EAST OF 88W.
 
GAP NORTHERLY WINDS IN THE GULF OF PANAMA REGION OF 20 KNOTS 
WILL CONTINUE TODAY AND WEDNESDAY THEN DIMINISH THURSDAY TO LESS 
THAN 20 KNOTS.

$$
LL