Rainfall across the Daly region was generally average to above average for the 2011–12 year (Figure C1). The area surrounding Pine Creek township recorded rainfall very much above the long-term average while rainfall in the northeast of the region was below normal. The total area-averaged rainfall over the Daly region during the 2011–12 year was 1,127 mm, which is above the long-term area-averaged rainfall of 1,034 mm.
Figure C1 Map of annual rainfall deciles for the Daly region during the 2011–12 year
Annual rainfall ranged from more than 1,600 mm in the northwest of the region to less than 700 mm in the southwest (Figure C2).
Figure C2 Map of total annual rainfall for the Daly region during the 2011–12 year
The wet conditions observed in the Daly region are consistent with the above average decile rainfall experienced across much of northern and eastern Australia. These wet conditions were a result of a La Niña event in the Pacific Ocean and warmer than average sea surface temperatures in the Australian region. La Niña conditions persisted from October 2011–March 2012 (Figure C3).
The area-averaged monthly rainfall was generally close to the long-term average throughout the 2011–12 year (Figure C3). March 2012 was the wettest month of the reporting period, recording almost double the rainfall usually received.
Figure C3 Graph of total monthly rainfall for the Daly region during the 2011–12 year compared with the long-term average and percentiles for the region
Evapotranspiration across the Daly region was generally above average for the 2011–12 year (Figure C4). The above average evapotranspiration reflects the above average rainfall experienced across the region, particularly during the early part of the wet season, October–December (see Rainfall). As a result of this rainfall, more water was available for evaporation, particularly given the above-average rainfall in October–December corresponded with the hottest part of the year (see Temperature).
Figure C4 Map of annual evapotranspiration deciles for the Daly region during the 2011–12 year
The total area-averaged evapotranspiration over the Daly region during the 2011–12 year was 904 mm, which is slightly above the long-term annual mean of 809 mm. Evapotranspiration ranged from 600 mm in the south to 1,200 mm in the north of the region (Figure C5).
Figure C5 Map of annual evapotranspiration for the Daly region during the 2011–12 year
The Daly region experienced mean temperatures generally average to below the long-term average during the 2011-12 year (Figure C6).
Figure C6 Map of annual mean temperature deciles for the Daly region during the 2011–12 year
Mean temperatures across the region generally ranged from 26 °C–28 °C across most of the region (Figure C7).
Figure C7 Map of annual mean temperature for the Daly region during the 2011–12 year
La Niña events are typically associated with cooler than average daytime temperatures in eastern parts of Australia from October to April. Monthly mean temperatures for the Daly region were generally close to the long-term average between October and April (Figure C8), which is broadly consistent with the typical effect of La Niña on temperatures.
June 2012 was the coolest month of the reporting period, recording an area-averaged mean temperature within the 10th percentile.
Figure C8 Graph of average monthly mean temperature for the Daly region during the 2011–12 year compared with the long-term average and percentiles for the region