Above average rainfall in the Otways gave a welcome boost to Geelong’s water storages in June. The immediate Geelong district was also mainly above average, but not to as great an extent, with most of the urban area recording over 45 mm for the month. Eastward across the Bellarine Peninsula, and northward from Avalon, low totals were the result of rain shadows effects of the Otways and Great Dividing Range.
Geelong’s temperatures were about 0.7 degree above average for June, despite the lowest figure of -0.2 on the 19th. Daily maxima were warmer despite the strong westerly winds, which tended to increase the wind chill factor.
Although often cold, wet and windy, and in that sense typical of winter in Geelong, June was still an interesting month for all weather-watchers. A number of phenomena were visible in the sky, and some were quite rare.
Take the moonbow on the evening of the 25th, seen by a reliable observer around 7 pm to our southwest. A full moon in the northeast provided the light source for this “rainbow at night” which showed up as a bright whitish arc, with just the hint of colours in it.
Numerous rainbows appeared and one was photographed in a partly-blue sky ovr Breakwater on the 13th.
A blue sky rainbow is not especially uncommon when very tiny invisible water droplets exist, but lightning without thunder is quite rare.
A cloud-to-ground lightning bolt was seen by another reliable observer over Belmont in the middle of the afternoon at the time a storm was occurring at Corio on the 16th. No thunder was audible – this is definitely not common.
A corona around the moon was photographed over Geelong on the 22nd. A corona occurs when a bright moon – in this case nearly full – shines through a thin layer of uniform altostratus cloud. A rainbow-like circle surrounds the moon’s disk.
Some very windy days were experienced – with Point Lonsdale recording gusts up to 109 kph on the 7th. Hail up to 2.5 cm across fell at Corio on the 12th.