Latest Southern Oscillation Index values

SOI values for 24 May 2013

Average for last 30 days	5.3
Average for last 90 days	6.2
Daily contribution to SOI calculation	13.4

Monthly average SOI values

February	-5.6
March	8.7
April	1.3

Note: Calculated using the 1887–1989 base period. This information is usually updated every weekday at 4:30pm (AEST), public holidays excluded.

Southern Oscillation Index (SOI)

• Recent (preliminary) Southern Oscillation Index (SOI) values
• SOI data files
• Graphs of monthly SOI values and SOI Phases, 1899-current