An extraordinarily severe localised thunderstorm on the 19th dropped 54 mm of rain on central Geelong. In less than half an hour, between 5.00 pm and 5.30 pm, a slow-moving thunderstorm cell gave Geelong one of the most intense rainfall events ever recorded here. Around 5.10 pm our recorder at Queens Park measured the equivalent of 433 mm per hour, or 7.3 mm per minute. This is a monsoonal-like deluge, very rarely seen in Geelong. Breakwater had 54 mm, including large hail, and Moolap 41 mm.
The cause was a rapidly-developing but slowly moving cell which was seen advancing on radar, but which took the Bureau of Meteorology by surprise when they only managed to issue a severe storm warning around 5.20 pm when it was nearly over. As the storm reached Geelong, Queens Park recorded 37 mm but ‘old’ Highton, only a kilometre away, only received 5 mm. Grovedale had 2 mm and Hamlyn Heights almost nil. On the northern side, North Geelong and Bell Post Hill had about 15 mm and Corio 10 mm. By the time this narrow feature reached Moolap (41 mm) it had started to die, and the Salt Works, Clifton Springs and Leopold did not benefit. The rapid intensification was due partly to the ‘trigger’ effect of rising warm air from the urban area as the storm reached Geelong.
As a result of this half-hour event occurring over the official rain gauge, Geelong recorded its well above average February total of 54.8 mm. The 30-year average is 38.0 mm and the long-term average 37.0 mm. Geelong Weather Services urban area average, a more accurate record of rainfall over the whole city, will credit Geelong with less than average rain for February 2014, as befits the situation in this case.
Summer rainfall was most disappointing, with Geelong receiving only around 65% (75 mm) of its normal total for the season (117 mm). Despite this, and a similar poor result for the catchment areas, the water catchments are still standing at a healthy 78% of capacity.
TEMPERATURE and OTHER FEATURES
February was warmer than average. Daily maximums averaged 26.3 degrees, and minimums 14.5 degrees, compared to the 30-year averages of 14.0 degrees and 25.1 degrees respectively.
There were five days above 30 degrees and the top was 38.8 degrees on the 2nd.
Summer overall was warmer than average as well, with a mean temperature of 19.8 degrees, the warmest since that of 2000-01.
There were three strong wind days, with a maximum gust of 72 kph at Breakwater on the 9th. Several days were misty and there were four consecutive days of smoke haze which drifted from the fires in Gippsland on the 11th to 14th. One severe storm on the 19th, with torrential rain and hail, flash flooded central areas, and caused some structural damage.