000
AXPZ20 KNHC 181532
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU JUN 18 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.

...SPECIAL FEATURE...

TROPICAL DEPRESSION ONE-E IS NEWLY FORMED AND LOCATED NEAR 18.2N 
108.5W 1005 MB...275 NAUTICAL MILES SW OF MANZANILLO MEXICO MOVING N 
8 KT. GOOD UPPER LEVEL OUTFLOW IS OVER THE SYSTEM. THIS OUTFLOW IS 
ENHANCED BY AN APPROACHING SHORTWAVE NORTHWEST OF THE CENTER. 
NUMEROUS MODERATE WITH SCATTERED STRONG CONVECTION IS SURROUNDING 
THE CENTER AND IS BEGINNING TO ORGANIZE BUT MOST OF THE CONVECTION 
IS SOUTH OF THE CENTER. THE CONVECTION IS WITHIN THE AREA FROM 14N 
TO 18N BETWEEN 107W AND 110W. THE DEPRESSION IS FORECAST TO BECOME A 
TROPICAL STORM LATE FRIDAY BEFORE MOVING INLAND OVER MAINLAND MEXICO 
FRIDAY NIGHT. HEAVY RAINS ASSOCIATED WITH THIS SYSTEM WILL AFFECT 
PORTIONS OF SW MEXICO DURING THE NEXT SEVERAL DAYS AS THE SYSTEM 
APPROACHES THE COAST AND MOVES INLAND.

...TROPICAL WAVE...

A TROPICAL WAVE IS NORTH OF 12N ALONG 93W/94W MOVING W 10 TO 15 KT. 
A LARGE AREA OF SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN 
110 NM EITHER SIDE OF LINE FROM 16N94W TO 09N101W. THE CONVECTION 
NEAREST THE WAVE HAS RECENTLY DIMINISHED AND THE CONVECTION SHOWS NO 
SIGNS OF BEING PART OF AN ORGANIZED CIRCULATION.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS ALONG THE LINE...04N77W TO 
06N95W TO 09N100W TO 07N120W TO 07N140W. SCATTERED MODERATE TO 
STRONG CONVECTION IS WITHIN 60 NM OF THE POINT 09N85W. SCATTERED 
MODERATE WITH ISOLATED STRONG CONVECTION IS WITHIN 60 NM EITHER SIDE 
OF THE ITCZ EAST OF 95W. SCATTERED MODERATE TO STRONG CONVECTION IS 
WITHIN 90 NM OF THE POINT 10.5N112.5W. SCATTERED MODERATE WITH 
ISOLATED STRONG CONVECTION IS WITHIN THE AREA FROM 07N TO 10.5N FROM 
126.5W TO 129.5W.

...DISCUSSION...

MIDDLE AND UPPER RIDGE IS NORTH OF 20N WEST OF 125W. RIDGE IS 
FORECAST TO PERSIST AND WEAKEN SLIGHTLY THROUGH THE NEXT SEVERAL 
DAYS. THE AREA NORTH OF 25N IS MOIST IN THE MIDDLE AND UPPER LEVELS 
BUT THE ENTIRE AREA OF THE RIDGE IS CLOUD FREE IN THE MIDDLE AND 
UPPER LEVELS WITH OVERCAST TO OCCASIONALLY BROKEN STRATOCUMULUS IN 
THE LOWER LEVELS.

WELL DEFINED SHORTWAVE IS OVER THE NORTHEAST PART OF THE PACIFIC 
OCEAN AREA. THE TROUGH IS NORTH OF 22N FROM 110W TO 125W. THE AREA 
IS DRY AND CLOUD FREE IN THE MIDDLE AND UPPER LEVELS WITH MOSTLY 
OVERCAST STRATOCUMULUS IN THE LOWER LEVELS. DIFFLUENT UPPER FLOW 
EAST OF THE TROUGH COUPLED WITH SOUTHERLY FLOW IS ADVECTING A 
MOISTURE PLUME FROM THE ITCZ NORTHWARD OVER A BROAD AREA 300 NM 
EITHER SIDE OF A LINE FROM NEAR 28N100W TO 15N106W TO 05N115W. THIS 
AREA INCLUDES THE TROPICAL DEPRESSION MENTIONED ABOVE. IT ALSO 
INCLUDED ANOTHER WEAKER LOW CENTERED NEAR 11N114W 109MB. THIS LOW IS 
WEAK AND FORECAST TO REMAIN WEAK AS IT DRIFTS WEST.

REMAINDER OF THE MIDDLE AND UPPER LEVELS IS ANALYZED AS A WEAK 
HEIGHT PATTERN.

THE AREA NORTH OF THE ITCZ EAST OF THE ABOVE MENTIONED MOISTURE 
PLUME IS DIFFLUENT ALOFT WITH MULTI LEVEL CLOUDS AND EMBEDDED AREAS 
OF CONVECTION.

WEAK SURFACE RIDGE IS NORTH OF 14N WEST OF 120W. ELSEWHERE EXCEPT AS 
MENTIONED ABOVE A BROAD TROUGH IS ANALYZED ELSEWHERE AT THE SURFACE.
 
$$
LL