000
AXPZ20 KNHC 170906
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC WED SEP 17 2008

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...
TROPICAL WAVE N OF 02N ALONG 81W INTO PANAMA MOVING W 10 KT. 
CONVECTION ASSOCIATED WITH THE SYSTEM IS E OF THE WAVE S OF THE 
ITCZ.

TROPICAL WAVE N OF 04N ALONG 92W MOVING W ABOUT 10 KT. MOST OF 
THE CONVECTION WITH THE WAVE IS S OF THE ITCZ.

TROPICAL WAVE FROM 3N TO 16N ALONG 115W MOVING W ABOUT 15 KT. NO 
SIGNIFICANT CONVECTION ASSOCIATED WITH THE WAVE.

...ITCZ...
ITCZ AXIS IS CENTERED FROM 9N84W TO 11N110W TO 12N130W TO 
10N140W. NUMEROUS MODERATE TO STRONG FROM 05N TO 10N BETWEEN 
83W-95W.

...DISCUSSION...
MID/UPPER LEVEL TROUGH MOVING OVER THE FAR NW PORTION OF THE 
DISCUSSION AREA HAS FLATTENED THE RIDGE THAT HAS BEEN OVER THE 
AREA THE LAST SEVERAL DAYS. THE TROUGH EXTENDS FROM 32N132W TO 
28N140W. UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED NEAR
22N119W WITH RIDGE EXTENDING E TO W ALONG 22N...WITH ANOTHER
ANTICYCLONIC CIRCULATION CENTERED OVER CENTRAL MEXICO NEAR 
22N99W. STRONG SUBSIDENCE WITH DRY STABLE CONDITIONS COVER THE
AREA N OF 15N W OF 115W. ONLY A FEW SHOWERS ARE NOTED ALONG THE 
ITCZ W OF 100W. 

ANOTHER UPPER LEVEL ANTICYCLONIC CIRCULATION OVER THE NW 
CARIBBEAN JUST OFF THE COAST OF HONDURAS. DIFFLUENT FLOW S OF 
THE ANTICYCLONIC CIRCULATION IS ENHANCING CONVECTIVE ACTIVITY 
ACROSS CENTRAL AMERICA AND THE PACIFIC N OF 4N W OF 95W. A WEAK 
TROUGH SEPARATES THE CARIBBEAN AND MEXICO ANTICYCLONES.

SURFACE RIDGE WITH AXIS EXTENDING FROM A 1022 MB HIGH PRES 
CENTER NEAR 29N133W TO 19N123W. BROKEN/OVERCAST STRATOCUMULUS 
CLOUDS COVER THE AREA N OF 20N W OF 115W. SURFACE TROUGH IS 
ANALYZED ALONG THE ITCZ FROM 7N-15N ALONG 130W. A FEW SHOWERS 
ARE ALONG THE TROUGH AXIS. 

$$
DGS