August 2011

RAINFALL

August was Geelong’s driest month for the year so far. The Breakwater Racecourse AWS recorded just 19.6 mm and the average for Geelong is around 49 mm. This means it falls within the lowest 10% of all recorded August rains since records began in 1871. The driest August was in 1982, when only 10 mm was received at North Geelong. Most of the region was well down in rainfall, with the Otways only receiving about 50-60% of normal. The Bellarine Peninsula was similarly affected and the Golden Plains-Bannockburn district as well as Anakie-Lara even drier.

Winter rainfall was around 80% of the long-term normal, and this was predicted accurately by the BoM 3-monthly outlook, itself an unusual occurrence. Winter rain at Geelong totalled 110 mm across the urban area and this was below the 30-year normal 140 mm.

The water supply catchments are stable on a very favourable 92.5% of capacity.

TEMPERATURES

Thanks to figures received from the BoM, it can be seen that the new AWS at Breakwater, because of its more urban location, tends to record temperatures at this time of year, around 0.6 degree C warmer than the old Airport station. The Breakwater AWS August figures of 6.4 C for minimums and 16.6 C for maximums seem to show a warmer month to the extent of around half a degree C. Full comparisons will be impossible to make until a new “normal” can be calculated. One can only hope that Geelong’s frequently-moved weather observation site can remain intact for at least the next 30 years, but, given some official lack of interest in Geelong’s ongoing weather record, this is highly doubtful. In the meantime we shall have to rely on estimations rather than by using incompatible data as if they were comparable. Geelong temperature figures since 1902 have been called a “hotch-potch” by independent climate analysts since they have been collected from at least five different sites across the city in the last 100 years when all the urban growth has occurred.

On the first 4 days of the month, the maximum temperatures averaged 21.3 C and represented the warmest start to August that Geelong has had. Highest maximum for the month was 22.8 C on the 3rd and lowest maximum 11.2 C on the 13th. Daily minimums ranged from 1.2 C to 12.7 C.

The winter overall seems to have been slightly warmer than “normal”. June was slightly cooler (by 0.3C?) and July slightly warmer (by 0.3C?), and August around 0.5C warmer as far as it is possible to judge in view of the foregoing.

OTHER FEATURES

Another very settled month saw many sunny and partly sunny days dominated by high pressure systems, which tended to block the effects and frequency of cold fronts. There were 3 frosts, including a minimum temperature of 1.2 C on the 12th and 1.9 C on the 13th. There was only one strong wind day with a gust of 65 kph on the 25th.

RAINFALL DATA

 

GEELONG REGION
Location Total for
Month
(mm)
Monthly
Average
(mm)
Aireys Inlet 36.4 78.5
Anakie (Granite Road) 14.4 46.0
Anakie (De Motts Road) 17.4 46.0
Anglesea na 69.0
Apollo Bay 68.8 124.7
Bacchus Marsh 7.9 39.0
Ballan 26.6 55.6
Ballarat 46.8 76.4
Bannockburn 16.8 47.0
Barwon Heads 24.8 63.0
Bells Beach na 60.4
Bellbrae na 60.4
Beeac 18.2 70.1
Benwerrin 31.6 164.0
Birregurra 43.0 80.3
Boonah 22.8 150.0
Cape Otway 41.6 102.1
Colac 48.0 59.5
Clifton Springs 26.6 52.0
Cressy 17.6 52.0
Curlewis 22.7 42.0
Dereel 33.0 62.0
Drysdale 29.2 54.9
Durdidwarrah 17.2 53.3
Forrest 30.2 146.2
Forrest (West Barwon) 74.4 146.2
Gellibrand na 103.2
Inverleigh 21.2 na
Johanna Heights 86.0 na
Lal Lal 20.2 na
Lavers Hill 130.0 na
Laverton 11.6 48.0
Little River West 12.5 38.0
Melba Gully na n.a.
Melbourne (City) 18.0 51.0
Meredith (Darra) 16.8 61.7
Moriac 28.0 58.0
Morrisons 18.0 80.3
Mt Cowley na 185.0
Mt Mercer 20.0 70.3
Mt Sabine 67.4 210.0
Ocean Grove na 45.0
Pollocksford 23.0 n.a.
Point Lonsdale 21.1 59.0
Queenscliff na 61.4
Scotsburn 36.6 80.3
Shelford na 51.0
Sheoaks 13.0 47.0
Skipton 41.0 48.0
St Leonards 28.0 60.0
Teesdale na 44.5
Torquay 27.5 64.0
Warncoort na 89.8
Weeaproinah na 232.8
Winchelsea 29.5 57.2
Wooloomanatta 10.6 47.2

GEELONG SUBURBS
Location Total for
Month
(mm)
Monthly
Average
(mm)
Avalon 19.0 48.3
Bell Park 23.1 50.9
Belmont 24.0 49.4
Breakwater 19.6 45.0
Connewarre 22.0 44.3
Corio 15.0 42.0
East Geelong 21.2 47.3
Grovedale 30.5 51.5
Hamlyn Heights 18.6 46.0
Highton na 51.5
Lara 12.8 39.6
Lara (Serendip) na 39.6
Leopold 22.0 49.5
Leopold East 33.6 49.5
Manifold Heights 21.8 46.0
Moolap 20.4 45.0
Mt Duneed West 32.1 48.1
Waurn Ponds 25.6 48.1
Whittington na 51.0
Urban Area Average 25.0 47.3