Not even the most confirmed atheist has any reason not to give thanks for the region’s great rainfall last month. Heavy August rains have increased catchment totals to over 56% of capacity, having increased by 6% in the last week alone. This is better than at any time since 2005, and has triggered a flood warning on the upper Barwon. For those who study model-based output it was instructive to note the failure of the BoM 3-monthly probability outlook, which predicted only a 30-35% chance of average falls in winter for this region.
The most spectacular result was at Weeaproinah, where 575 mm fell in August, eclipsing the previous total of 472 mm set in 1939, and providing in 4 weeks what Geelong usually takes more than a full year to accumulate. The figures go back to 1901. In this La Nina year this is a significant event. Weeaproinah also broke its all time monthly record of 538 mm set in June 1952.
Winter rains compared to average: Weeaproinah 899 (674 mm average), West Barwon Dam 432 (410 mm), Apollo Bay 433 (351 mm), Aireys Inlet 233 (221 mm), Geelong Airport – Mt Duneed 148 (140 mm), Waurn Ponds 153 (134 mm), Bell Post Hill 167 (144 mm), Barwon Heads 216 (179 mm), Leopold 198 (160 mm), Bellbrae 220 (184 mm), Lara 100 (115mm) and Anakie 144 (144 mm).
Some areas to our northwest, from Lara to Anakie and the Moorabool catchment were not quite as fortunate over winter, but their August rainfalls were generally above average.
It was Geelong’s coldest winter since 1998 and its 2nd coldest in 19 years of Airport figures at Mt Duneed. Mean daily winter temperature this year was 9.6 degrees C, and the long-term daily mean is 10.1 degrees C. All 3 winter months were colder than average, June by 0.5C, July by 0.2C and August by 0.85C.
August was nearly a full degree colder than average. Daily maximums averaged 13.5 degrees and minimums averaged 5.6 degrees. These figures are 1.5 and 0.2 degrees below the means of 15.0 and 5.8 degrees respectively established at Geelong Airport 1992-2009. Average daily temperature last month therefore was 0.85 degree below normal.
Coldest overnight temperature was 2.2 degrees C on the 7th, and the warmest day reached 17.7 degrees C on the 30th.
There were 9 days where wind gusts exceeded 60 kph, including speeds of 76 kph recorded at Mt Duneed on both the 24th and 25th. On 2 occasions small hail fell, but there were no severe storms. One thunder day occurred without incident.