Geelong urban area recorded around a disappointing 20mm for March compared to the average 30mm. Rain fell on an average 10 days – mainly in the final week – and the largest fall was 10.4mm by 9am on the 27th at Mt Duneed. The Otways catchments fared better with totals around the March average; Mt Sabine recording 80mm and West Barwon 60mm. But the Golden Plains district to Geelong’s immediate northwest received only a drought-like 40-50% of its normal March totals. Teesdale received 12mm and Lal Lal only 18mm. Even the final week of the month, which promised heavy rains from several cold fronts and troughs, was disappointing owing to the frustratingly efficient operation of the infamous “Geelong rain shadow.”
Current catchment levels are only 28% of capacity and the West Barwon Dam is still only one third full.
Geelong in March was 1.5 degrees above average. Average daily minimum was 11.7C and average daily maximum was 26.0C. This (26 degrees C) was Geelong’s highest figure for March maximums, but average temperatures also have to take account of minimum figures. March long-term averages are 12.0C for minimums and 22.9C for maximums. There were 8 days over 30 degrees (normally 4) and on 3 of these the maximum exceeded 40C. This March equalled the record of eight days over 30C set in 1982. The top temperature of 41.5C on the 16th was a new record for March, beating the 41.1C set in 1934. Overall it was not one of Geelong’s warmest Marches, because the high maximums were counteracted by lower minimums. The warmest March occurred in 1974.
It was a month of hot nights up until the final week. An unusual anomaly occurred on the night of the 13th-14th, when the temperature did not drop below 24.8C; this would have created another new record except that the temperature recording convention extends over a 24-hour period from 9am to 9am and a lower minimum (16.0C) had been recorded on the previous night. At midnight on the 17th-18th the temperature was 30.5C.
In the last week of the month maximum temperatures fell dramatically to a more wintry pattern as cloudier skies and rainfall returned. Coldest overnight temperature was 6.3C on the 30th whereas the warmest minimum was 20.1C on the 18th.
There were two thunder days but no severe storms in Geelong, and only 3 days of strong winds where gusts exceeded 60kph at Mt Duneed. Top gust was 74kph from the northwest on the 14th.
On the 26th a severe thunderstorm dropped 85mm in 90 minutes on Moonlight Head on the Western Otways coast, causing flash flooding of local properties, but Lavers Hill, just a few kilometres away, received only 5mm, despite an amazing thunder and lightning display. A similar sound and light show occurred over Geelong the following night, but little rain eventuated.
In a month of extremes, on the 19th Geelong was shrouded by a pall of smoke blown from bushfires in NW Tasmania across Bass Strait, causing a salutary reminder of similar danger in our region.