Agriculture Weather
Southern Oscillation Index
The Southern Oscillation Index (SOI) is calculated from the monthly or seasonal fluctuations in the air pressure difference between Tahiti and Darwin.
A strongly and consistently positive SOI pattern (e.g. consistently above about +6 over a two month period) is related to a high probability of above the long-term average (median) rainfall for many areas of Australia, especially areas of eastern Australia (including northern Tasmania) - La Niña.
Conversely, a 'deep' and consistently negative SOI pattern (less than about minus 6 over a two month period, with little change over that period) is related to a high probability of below median rainfall for many areas of Australia at certain times of the year - El Niño.
However, it is important to remember that the pattern of relationship between SOI and rainfall (and temperature) can vary depending on the particular season and region. Additionally, the change in SOI over a specified period can be as important in understanding relationships between SOI and rainfall as is the absolute value in SOI.
Southern Oscillation Index
Nino3.4 Index
-
Display your Local Weather here
automatically each time you visit us:
Rotates through Temperature,
Wind, Humidity and RainUse the Search Bar above
to find your Local, and go to the Local page
Click "Set My Local"
button next to the location name
Weather News
Severe weather system off NSW heading for Illawarra, South Coast
12:37 EST
NSW coastal communities are being warned to brace for heavy rain and flash flooding as a wild weather system forms off the east coast.
Walnut demand grows amid shortage of Australian producers
11:13 EST
Australian walnut growers are expecting a potential record harvest in the year ahead as drought conditions ease and overseas demand grows.
