000
AXPZ20 KNHC 270922
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON APR 27 2009

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 
0845 UTC.

...ITCZ...

THE INTER TROPICAL CONVERGENCE ZONE IS ALONG THE LINE...05N77W 
TO 06N105W TO 06N140W. SCATTERED MODERATE TO STRONG CONVECTION 
IS WITHIN 120 NM OF THE POINT 07N108W. SCATTERED MODERATE WITH 
ISOLATED STRONG CONVECTION IS WITHIN 120 NM OF THE POINT 
05N118.5W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION IS 
WITHIN 60 NM OF THE POINT 08N128.5W. SCATTERED MODERATE TO 
STRONG CONVECTION IS WITHIN 160 NM OF THE POINT 06.5N133.5W.

...DISCUSSION...

THE PATTERN WILL NOT CHANGE MUCH IN THE NEXT SEVERAL DAYS. A 
MIDDLE AND UPPER LEVEL SHORTWAVE IS OVER NORTHERN MEXICO AND IS 
MOVING EAST BUT ANOTHER SHORTWAVE WILL MOVE INTO THE AREA 
CONTINUING THE OVERALL PATTERN. THIS FEATURE IS CAUSING LITTLE 
WEATHER IN OUR AREA BUT IS CONTRIBUTING TO CONVECTIVE ACTIVITY 
TO THE EAST OF THE SHORTWAVE OVER THE SOUTHERN PART OF THE 
UNITED STATES GREAT PLAINS WHERE UPPER DIFFLUENCE MEETS LOWER 
LEVEL GULF OF MEXICO MOISTURE...BUT IN OUR AREA LITTLE WEATHER 
IS ASSOCIATED WITH THESE SHORTWAVES.

A DEEP LAYER FULL LATITUDE TROUGH IS JUST WEST OF THE AREA NORTH 
OF THE ITCZ WITH AN AXIS ALONG ABOUT 143W. THE SOUTHERLY 
DIFFLUENT DEEP LAYER FLOW EAST OF THE TROUGH IS AFFECTING THE 
AREA WEST OF 120W WITH DEEP LAYER MOISTURE AND MULTI LEVEL 
BROKEN TO OVERCAST CLOUDS. ENHANCED ITCZ CONVECTION IS ALSO 
NOTED WEST OF 120W. THIS FEATURE IS FORECAST TO REMAIN STRONG 
AND TO BE STATIONARY WITH THE SAME WEATHER PATTERN CONTINUING 
FOR THE NEXT SEVERAL DAYS.

A MAINLY UPPER TROUGH RUNS FROM THE NORTHWEST CARIBBEAN ACROSS 
EASTERN MEXICO AND NORTHERN CENTRAL AMERICA TO THE ITCZ NEAR 
100W. THIS FEATURE IS ALSO EXPECTED TO PERSIST THROUGH THE NEXT 
SEVERAL DAYS. ASSOCIATED WEATHER CONSISTS OF SOME ITCZ 
CONVECTION AND THE ADVECTION OF DEEP LAYER MOISTURE AND SOME 
CLOUDINESS OVER CENTRAL AMERICA TO THE EAST OF THE TROUGH AXIS.

THE REMINDER OF THE MIDDLE AND UPPER LEVELS IS BROAD 
ANTICYCLONIC FLOW. 

AT THE SURFACE A MODERATE RIDGE IS NORTH OF THE ITCZ WEST OF 
110W. ELSEWHERE A BROAD SURFACE TROUGH IS ANALYZED.

NORTHEAST TO EAST GAP WINDS OF 20 TO OCCASIONALLY 25 KNOTS IN 
THE GULF OF PAPAGAYO REGION WILL CONTINUE THROUGH THE NEST 
COUPLE OF DAYS THEN DIMINISH.

$$
LL