000
AXPZ20 KNHC 112122
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT SEP 11 2010

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 
1830 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED FROM 11N110W 
TO 13N132W TO 11N140W. A LOW PRES SYSTEM IS EMBEDDED IN THE ITCZ 
NEAR 13N134W WITH SCATTERED MODERATE CONVECTION NOTED WITHIN 150 
NM E QUADRANT OF THE LOW. SCATTERED MODERATE CONVECTION IS 
WITHIN 120 NM S AND 60 NM N OF THE ITCZ AXIS BETWEEN 109W AND 
112W...WITHIN 45 NM S AND 90 NM N OF THE ITCZ AXIS BETWEEN 120W 
AND 126W...AND ELSEWHERE WITHIN 75 NM EITHER SIDE OF THE ITCZ 
AXIS W OF 130W.

...DISCUSSION...

N OF 20N...
AN UPPER RIDGE AXIS BETWEEN ANTICYCLONES LOCATED E OF THE AREA 
NEAR 31N102W AND W OF THE AREA NEAR 19N142W IS DIVIDED BY AN 
UPPER TROUGH EXTENDING FROM N OF AREA THROUGH 32N130W TO 
23N127W. THIS TROUGH IS ATTEMPTING TO PICK UP A WEAK UPPER LOW 
LOCATED NEAR 20N127W. HOWEVER...THE FORECAST CALLS FOR THE 
TROUGH TO GRADUALLY MOVE NE INTO THE CALIFORNIA OVER THE NEXT 
FEW DAYS...LEAVING THIS LOW BEHIND. A WEST-SOUTHWESTERLY UPPER 
JET WILL MOVE INTO FAR N WATERS BEHIND THIS TROUGH BY MON. 
SCATTERED MODERATE CONVECTION LIES UNDER THE DIFFLUENT UPPER 
RIDGE AXIS WITHIN 60 NM OF THE EASTERN SHORE OF THE CENTRAL GULF 
OF CALIFORNIA FROM 26N TO 28N. THERE ARE NO OTHER AREA OF 
SIGNIFICANT CONVECTION N OF 20N AND SCATTEROMETER DATA FROM 
OVERNIGHT SHOWS NO AREAS OF WINDS OVER 20 KT. HOWEVER...NW WINDS 
ALONG THE W COAST OF BAJA CALIFORNIA ARE INCREASING THIS 
AFTERNOON AS THE PRESSURE GRADIENT BETWEEN TROUGHING IN THE GULF 
OF CALIFORNIA AND THE SUBTROPICAL RIDGE EXTENDING FROM 31N130W 
TO 20N110W BUILDS. SHIP A8FU7 NEAR 26N116W AT 1800 UTC REPORTED 
18 KT NW WINDS.

S OF 20N...
THE ITCZ CONTINUES TO BE BROKEN UP BY SOUTHWEST FLOW EXTENDING 
FROM ABOUT 05N TOWARD THE COAST OF SOUTHERN MEXICO AND GUATEMALA 
GENERALLY BETWEEN 90W AND 100W AS SEEN IN SHIP...BUOY...AND 
SCATTEROMETER OBSERVATIONS. A WEAK SURFACE TROUGH IS ANALYZED 
NEAR THE WESTERN EDGE OF THIS SW FLOW FROM 15N98W TO 10N106W. 
WIDELY SCATTERED MODERATE CONVECTION CAN BE FOUND FROM 07N TO 
10N E OF 100W AS WELL AS FROM 04N TO 10N E OF 86W. THIS 
CONVECTION LIES UNDER A REGION OF BROAD UPPER LEVEL DIFFLUENCE 
BETWEEN THE E TO SE UPPER FLOW ON THE SW SIDE OF THE 
AFOREMENTIONED EXPANSIVE ANTICYCLONE E OF THE FORECAST AREA AND 
NE TO E UPPER WINDS NEAR THE EQUATOR. FARTHER W...A 1012 MB 
SURFACE LOW EMBEDDED IN THE ITCZ NEAR 13N134W HAS 20 KT WINDS 
ASSOCIATED WITH IT AND SCATTERED MODERATE CONVECTION NOTED 
WITHIN 150 NM E QUADRANT OF THE LOW. THIS LOW IS EXPECTED TO 
REMAIN RELATIVELY STATIONARY OVER THE NEXT FEW DAYS.

$$
SCHAUER