Recent (preliminary) Southern Oscillation Index (SOI) values
Tahiti = Barometric pressure (daily reading)
Darwin = Barometric pressure (daily reading)
30 day Av.SOI = Average daily SOI value for the previous 30 days.
90 day Av.SOI = Average daily SOI value for the previous 90 days.
Note: Calculated using the 1887-1989 base period. This information
is usually updated every weekday at 2:00pm (AEST), public holidays excluded.
** Daily values are not the SOI but contribute to the calculation of the
monthly SOI. Daily values are presented for research purposes only. 30 day (or larger) average SOI values are the key indices for forecast purposes.
If you are looking for data prior to that given below, see SOI data files.
| Date | Tahiti | Darwin | Daily** | 30 day avg SOI | 90 day avg SOI |
|---|---|---|---|---|---|
| 26 Apr 2013 | 1012.97 | 1012.10 | -10.96 | 5.38 | 2.15 |
| 27 Apr 2013 | 1012.47 | 1012.05 | -14.21 | 4.43 | 2.00 |
| 28 Apr 2013 | 1012.75 | 1011.75 | -10.02 | 3.56 | 1.85 |
| 29 Apr 2013 | 1012.89 | 1012.15 | -11.90 | 2.55 | 1.75 |
| 30 Apr 2013 | 1012.19 | 1012.10 | -16.59 | 1.33 | 1.62 |
| 1 May 2013 | 1011.29 | 1010.70 | -7.18 | 0.27 | 1.62 |
| 2 May 2013 | 1010.78 | 1009.40 | -1.13 | -0.04 | 1.90 |
| 3 May 2013 | 1010.76 | 1009.60 | -2.82 | -0.41 | 2.39 |
| 4 May 2013 | 1010.56 | 1010.65 | -12.39 | -1.26 | 2.73 |
| 5 May 2013 | 1009.29 | 1011.50 | -28.63 | -2.42 | 2.78 |
| 6 May 2013 | 1008.29 | 1010.05 | -25.18 | -3.24 | 2.85 |
| 7 May 2013 | 1009.71 | 1009.05 | -6.65 | -3.71 | 3.10 |
| 8 May 2013 | 1011.71 | 1009.70 | 3.70 | -3.85 | 3.41 |
| 9 May 2013 | 1012.96 | 1010.50 | 7.14 | -3.68 | 3.75 |
| 10 May 2013 | 1012.84 | 1010.45 | 6.61 | -3.63 | 4.02 |
| 11 May 2013 | 1013.44 | 1010.60 | 10.05 | -3.88 | 4.20 |
| 12 May 2013 | 1013.99 | 1010.05 | 18.48 | -3.72 | 4.41 |
| 13 May 2013 | 1013.93 | 1011.35 | 8.06 | -3.24 | 4.49 |
| 14 May 2013 | 1013.86 | 1009.70 | 20.16 | -2.05 | 4.71 |
| 15 May 2013 | 1014.11 | 1009.15 | 26.29 | -1.11 | 4.91 |
| 16 May 2013 | 1015.83 | 1009.65 | 35.64 | -0.29 | 5.24 |
| 17 May 2013 | 1016.57 | 1010.95 | 31.35 | 0.35 | 5.49 |
| 18 May 2013 | 1015.58 | 1011.35 | 20.70 | 0.65 | 5.63 |
| 19 May 2013 | 1014.50 | 1010.80 | 16.64 | 1.13 | 5.70 |
| 20 May 2013 | 1015.01 | 1010.75 | 20.93 | 2.10 | 5.78 |
| 21 May 2013 | 1015.80 | 1011.25 | 23.15 | 3.36 | 5.90 |
| 22 May 2013 | 1015.60 | 1010.55 | 26.98 | 4.37 | 6.03 |
| 23 May 2013 | 1015.06 | 1011.00 | 19.40 | 4.83 | 6.09 |
| 24 May 2013 | 1014.27 | 1011.00 | 13.35 | 5.30 | 6.18 |
| 25 May 2013 | 1013.78 | 1012.75 | -3.81 | 5.24 | 6.21 |
Last updated: 29 June 2010