000
AXPZ20 KNHC 112114
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON MAY 11 2009

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS ALONG THE LINE...06N77W TO 
06N110W TO 06N140W. SCATTERED MODERATE CONVECTION IS WITHIN 100 
NM OF THE POINT 06N81W. SCATTERED MODERATE TO STRONG CONVECTION 
IS WITHIN 45 NM EITHER SIDE OF A LINE FROM 09N84W TO 05N87W. 
SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION IS WITHIN THE 
AREA FROM 08N TO 10.5N BETWEEN 93W TO 105W. SCATTERED MODERATE 
TO STRONG CONVECTION IS WITHIN 120 NM OF THE POINT 07N110W. 
SCATTERED MODERATE CONVECTION IS WITHIN 120 NM OF THE POINT 
13.5N113.5W. SCATTERED MODERATE CONVECTION IS WITHIN 75 NM OF 
THE POINT 04N134W.

...DISCUSSION...

A DEEP LAYER TROUGH IS OVER THE EASTERN PART OF THE AREA EAST OF 
95W. AN EXTENSIVE AREA OF DEEP LAYER MOISTURE WITH MULTI LEVEL 
OVERCAST CLOUDS EXTENDS FROM THE ITCZ NORTHWARD OVER CENTRAL 
AMERICA EAST OF 86W. THIS MOISTURE EMANATES FROM ENHANCED ITCZ 
CONVECTION.

A MUCH LARGER CYCLONIC CIRCULATION IS CENTERED NEAR 17N123W. 
ASSOCIATED WITH THIS CIRCULATION IS ANOTHER EXTENSIVE AREA OF 
DEEP LAYER MOISTURE WITH MULTI LEVEL OVERCAST CLOUDS THAT 
EXTENDS EAST OF A LINE FROM THE CENTRAL GULF OF CALIFORNIA NEAR 
28N112W TO THE ITCZ NEAR 119W...THE AREA EXTENDS EAST TO ABOUT 
95W. ENHANCED CONVECTION IS WITHIN THIS AREA SOUTH OF 15N AND 
THE MOISTURE EMANATES FROM THIS CONVECTION INCLUDING CONVECTION 
WITHIN THE ITCZ. FROM THE ITCZ TO 25N WEST OF THIS AREA OF 
MOISTURE THE ATMOSPHERE IS DRY AND CLOUD FREE IN THE MIDDLE AND 
UPPER LEVELS. NORTH OF 25N THE MIDDLE AND UPPER LEVELS ARE 
SOMEWHAT MOIST BUT ARE STILL CLOUD FREE. 

REMAINDER OF THE MIDDLE AND UPPER LEVELS ARE A FLAT HIGHT 
PATTERN.

WEAK SURFACE RIDGE IS NORTH OF 15N WEST OF 105W. A SURFACE 
TROUGH IS NEAR 119W FROM 13N TO 05N. THIS TROUGH HAS BEEN 
ASSOCIATED WITH ENHANCED CONVECTION IN THE ITCZ BUT IT NOW 
APPEARS THAT THE TROUGH IS MOVING WEST OF THE CONVECTION. 
REMAINDER OF THE AREA IS ANALYZED AS A BROAD TROUGH.

GAP NORTHEAST TO EAST WINDS IN THE GULF OF PAPAGAYO REGION WILL 
OCCASIONALLY REACH 20 KT MAINLY IN THE NIGHTTIME HOURS.
 
$$
LL