000
AXPZ20 KNHC 270916
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON JUL 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 
0900 UTC.

...TROPICAL WAVES...
TROPICAL WAVE N OF 6N ALONG 96W MOVING W 20 KT. STRONG 
CONVECTION IS N OF 14N E OF THE WAVE TO 103W DUE MAINLY TO UPPER 
LEVEL DIFFLUENT FLOW.

TROPICAL WAVE N OF 6N ALONG 105W MOVING W 15-20 KT. SCATTERED
SHOWERS AND ISOLATED TSTMS ARE WITHIN 180 NM E AND 120 NM E OF 
THE WAVE.
 
TROPICAL WAVE FROM 6N-16N ALONG 120W MOVING W 15-20 KT. 
SCATTERED MODERATE TO STRONG CONVECTION FROM 13N-15N BETWEEN 
117W-120W.

TROPICAL WAVE FROM 4N-12N ALONG 127W MOVING W 15-20 KT.
SCATTERED MODERATE TO STRONG CONVECTION IS FROM 8N-13N BETWEEN
125W-128W.

...ITCZ...
AXIS IS ALONG 8N78W 11N95W 9N100W 11N115W 6N140W. SCATTERED 
STRONG CONVECTION WITHIN 110 NM S OF AXIS E OF 80W. SCATTERED 
MODERATE TO STRONG CONVECTION WITHIN 120 NM S OF AXIS FROM
109W-118W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 
180 NM N AND 60 NM S OF AXIS FROM 125W-135W.

...DISCUSSION...
AN UPPER LEVEL TROUGH EXTENDS FROM CYCLONIC CIRCULATION N OF THE 
DISCUSSION AREA NEAR 35N138W WITH TROUGH FROM THE CIRCULATION TO 
32N138W TO 10N130W. HIGH LEVEL MOISTURE IS ROTATING AROUND THE 
CYCLONIC CIRCULATION AND TROUGH. OTHERWISE MODERATE TO STRONG 
SUBSIDENCE WITH DRY STABLE AIR AT THE MIDDLE AND UPPER LEVELS OF 
THE ATMOSPHERE IS N OF THE ITCZ TO 25N BETWEEN 122W-133W.
 
A LARGE UPPER ANTICYCLONIC CIRCULATION IS CENTERED OVER NW 
MEXICO NEAR 19N112W WITH A RIDGE EXTENDING S ACROSS BAJA 
CALIFORNIA THEN INTO THE PACIFIC TO 15N115W. SLY FLOW AROUND
THE WESTERN PERIPHERY OF THE ANTICYCLONIC CIRCULATION IS 
ADVECTING HIGH LEVEL MOISTURE FROM ITCZ CONVECTION TO SOUTHERN
CALIFORNIA. 

A SHARP UPPER LEVEL TROUGH WITH AXIS THAT EXTENDS FROM THE N 
CENTRAL GULF OF MEXICO ACROSS CENTRAL MEXICO TO A CYCLONIC 
CIRCULATION OFF THE W CENTRAL COAST OF MEXICO NEAR 18N105W. AN 
UPPER LEVEL ANTICYCLONIC CIRCULATION HAS MOVED OVER GULF OF 
TEHUANTEPEC NEAR 15N95W. DIFFLUENT FLOW ALOFT BETWEEN THE UPPER 
TROUGH AND THE ANTICYCLONIC CIRCULATION IS ENHANCING STRONG 
CONVECTIVE ACTIVITY NW OF THE GULF OF TEHUANTEPEC.

SURFACE RIDGE WITH AXIS FROM 32N137W TO 17N105W. BROKEN/OVERCAST 
STRATOCUMULUS CLOUDS COVER THE AREA N OF 20N W OF 120W.

LARGE SOUTHERLY SWELLS THAT HAVE BEEN CROSSING THE EQUATOR FROM 
THE SOUTHERN HEMISPHERE THE PAST SEVERAL DAYS OVER THE SE 
PORTION OF THE DISCUSSION AREA ARE STARTING TO SUBSIDE.

$$
DGS