December 2009

RAINFALL

Generally rainfall in December was below average across the Geelong-Otways Region. Urban Geelong received falls between 25 and 35 mm, compared with the December average 41mm. Rain fell on just 6 days and the heaviest recorded was a fall of around 20mm across Geelong on the 18th. On New Year’s Eve a spectacular electrical storm, which caused only minor damage locally, crossed Geelong in time to compete with the New Year’s fireworks display, but the 10 mm of rain which fell will be included in the January 2010 figure since it fell after 9am. In an impressive localised downpour, the Lara-Little River-You Yangs area recorded 15-20mm on Christmas Eve, despite only 4mm falling in the city.

While some parts of the Otways ridge received a little above average rain (Lavers Hill, Johanna and Weeaproinah) most of the Barwon catchment was below average, although West Barwon Dam recorded close to its December normal.

Catchments are still holding around 35% of their capacity.

TEMPERATURE & OTHER FEATURES

December was warmer than average by about 0.9 degree C. Daily minimums averaged 10.7 (BoM long term published average 11.0) and maximums averaged 24.7 C (BoM long term published average 22.6). Despite this, December figures since 1903 still show an overall flat trend with no noticeable long-term changes, although some short-term fluctuations have occurred, typical of any climate. The change of BoM site in 1983 from North Geelong to Mt Duneed shows an inconclusive result because comparison figures were not continued for a long enough period. The total yearly raw Bureau of Meteorology (BoM) figures also show no overall warming in Geelong in over 100 years, despite the alarmist claims originating from some BoM researchers who ought to know better.

There were 5 days over 30 degrees in December this year (the average is 5) and the top was 40.4 C, reached on the 16th. There were 4 very windy days and the maximum gust was 74 kph, recorded on both the 3rd and the 31st. There was one thunder-lightning day with a storm on New Year’s Eve, but only minor damage and just one total fire ban day on the 16th. For a complete summary of the year’s weather, please see the separate annual summary.

RAINFALL DATA

GEELONG REGION
Location Total for
Month
(mm)
Monthly
Average
(mm)
Aireys Inlet 48.4 34.0
Anakie 31.8 55.0
Anglesea na 48.0
Apollo Bay 63.6 63.2
Bacchus Marsh 27.2 47.1
Ballan 40.8 45.9
Ballarat 32.0 51.6
Bannockburn 30.2 42.0
Barwon Heads 32.4 47.0
Bellbrae 37.0 54.0
Bells Beach na 54.0
Beeac 46.4 42.4
Benwerrin 60.4 n.a.
Birregurra 41.2 42.4
Boonah 64.2 n.a.
Cape Otway 40.2 52.7
Clifton Springs 37.6 n.a.
Colac 51.8 46.6
Cressy 40.4 42.7
Curlewis 34.2 44.2
Dereel na 44.2
Drysdale na 44.7
Durdidwarrah 43.2 55.1
Fiskville na n.a.
Forrest 60.0 60.3
Gellibrand na n.a.
Gerangamete 34.4 n.a.
Inverleigh na 45.5
Johanna 87.4 na
Lake Colac na 45.5
Lal Lal 36.8 n.a.
Lavers Hill 115.0 90.0
Laverton 32.4 45.0
Lethbridge na 55.9
Melba Gully na n.a.
Melbourne (City) 55.0 59.0
Meredith na n.a.
Meredith (Darra) 58.4 51.8
Moriac 34.5 n.a.
Mt Buninyong na n.a.
Mt Cowley 52.2 85.0
Mt Mercer na n.a.
Mt Sabine 52.6 90.0
Point Lonsdale 31.8 45.0
Pollocksford 32.8 n.a.
Portarlington na 45.5
Queenscliff na 43.4
Shelford na 45.0
Sheoaks 28.0 29.2
Skipton 31.5 46.4
St Leonards na 45.0
Teesdale na 39.9
Torquay 39.0 40.0
Warncoort na n.a.
Weeaproinah 113.8 112.9
West Barwon 65.6 65.0
Winchelsea na 41.1
Wooloomanata na n.a.
You Yangs 35.0 n.a.
GEELONG SUBURBS
Location Total for
Month
(mm)
Monthly
Average
(mm)
Avalon 30.0 28.1
Bell Park 29.9 47.8
Belmont 30.6 44.0
Connewarre 30.5 52.1
Ceres na 44.0
City 25.0 40.9
Corio 31.0 42.0
Grovedale 33.5 44.2
Grovedale South 32.5 44.2
Hamlyn Heights 30.7 57.0
Highton na 44.2
Lara 33.0 42.0
Lara (Serendip) 29.8 42.0
Leopold 35.0 53.9
Leopold East 39.7 42.0
Manifold Heights 32.2 47.8
Moolap 35.2 38.0
Mt Duneed Airport 32.6 41.0
Mt Duneed West na 42.2
Waurn Ponds 30.4 42.2
Whittington na 42.0
Urban Area Average 30.0 41.0