Daily climate maps
These maps (click for full sized versions) are updated daily and are based on data from our National Climate Database.
All historical averages are based on the 30-year period 1981-2010. Maps of some variables, for example sunshine hours, are based on fewer recording sites than others, for example rainfall. For more information on these maps, and the data used to produce them, please contact the National Climate Centre.
The Standardised Precipitation Index (SPI) is a simple measure of drought (and also of very wet conditions) and is based solely on the accumulated precipitation for a given time period (e.g. over the last 30 or 60 days). Because droughts vary greatly in duration, it is important to detect and monitor them at a variety of time scales.
SPI is calculated by taking the difference between the recently-accumulated precipitation and the long-term average (1981-2010) accumulated precipitation for the same dates, and then dividing by the long-term standard deviation (this is the "standardising" part). As a result, the severity of a drought can be compared to the average condition for any location and maps can be drawn. Values of the SPI range from +2.00 and above (extremely wet) to -2.00 and less (extremely dry) with near normal conditions ranging from +0.99 to -0.99.
Reusing these maps
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