000
AXPZ20 KNHC 280926
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC THU MAY 28 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 
0900 UTC.

...TROPICAL WAVES...

A TROPICAL WAVE IS ALONG 85W/86W N OF 02N EXTENDING NORTH TO 
WESTERN NICARAGUA. THE WAVE IS MOVING WEST AT 15-20 KT. 
ASSOCIATED CONVECTION IS NORTH OF 05N AND THE CONVECTION APPEARS 
TO BE MOVING WEST OF THE WAVE AND NOT TENDING TOWARD AN 
ORGANIZED PATTERN NEAR THE WAVE. 

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS ALONG THE LINE...07N77W TO 
07N110W TO 08N120W TO 03N135W TO 03N140W. SCATTERED MODERATE TO 
STRONG CONVECTION IS WITHIN 120 NM OF THE POINT 08N86.5W. 
SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION IS WITHIN 150 
NM OF THE POINT 08N98.5W. SCATTERED MODERATE TO STRONG 
CONVECTION IS WITHIN THE AREA FROM 05N TO 080N FROM 109W TO 116W.

...DISCUSSION...

UPPER LEVELS
WEAK TO MODERATE WESTERLIES ARE NORTH OF 18N WITH BROAD FLAT 
ANTICYCLONE SOUTH OF 18N. TWO SHORTWAVES ARE WITHIN THE 
WESTERLIES ONE IS NORTH AND EAST OF A LINE FROM THE BIG BEND 
REGION OF TEXAS ACROSS CENTRAL MEXICO TO 20N117W TO 32N117W. 
THIS AREA IS DRY AND CLOUD FREE IN THE MIDDLE AND UPPER LEVELS 
EXCEPT FOR SOME CONVECTION AT THE EAST END OF THE WAVE THAT IS 
OVER TEXAS. ANOTHER SHORTWAVE IS OVER THE NORTH CENTRAL PART OF 
THE AREA NORTH OF 20N FROM 120W TO 133W. A CYCLONIC CIRCULATION 
IS WITHIN THIS TROUGH AND IS CENTERED NEAR 31.5N126W AND IS 
MOVING EAST NORTHEAST AT ABOUT 20 KNOTS. THIS FEATURE SHOULD 
CONTINUE THIS MOTION AND REACH SOUTHERN CALIFORNIA FRIDAY. AT 
THIS TIME THERE IS LITTLE WEATHER ASSOCIATED WITH THE FEATURE.
THE OVERALL PATTERN WILL NOT CHANGE MUCH IN THE NEXT SEVERAL 
DAYS.

DIFFLUENT FLOW ALOFT EAST OF A LINE FROM 15N105W TO THE ITCZ 
NEAR 120W IS ENHANCING THE AREAS OF CONVECTION MENTIONED IN THE 
ITCZ SECTION.

SURFACE
WEAK SURFACE RIDGE IS NORTH OF THE ITCZ WEST OF 110W. EXCEPT FOR 
THE TROPICAL WAVE THE REMAINDER OF THE AREA IS ANALYZED AS A 
WEAK TROUGH.

$$
LL