Submitted by Bill Caulfeild-Browne
Several years ago, when he came to Tobermory to address the Sources of Knowledge Forum, I asked David Phillips if he could explain an anomaly I had observed with respect to September temperatures.
Over the years, September has almost always shown a bigger departure from historical norms than any other month. In 2002 for example, the mean was 17.7C, a whopping 3.2C above 20th century means. David had no explanation but did note he had seen this too. My only thought is that it might be related to the temperature of the lake if we have been having sunnier weather this century – Labour Day is often the most swimmable time for Georgian Bay.
As I do not have sunshine statistics for the last century, this will remain an unproven theory. But this September continued to be the warmest month of the year in terms of its departure from normal – 16.5C or 2C higher than historically. The warmest day was the 12th at 24.9C and the coolest was 7.9C on the 25th.
Rainfall was less than normal. All but 10 mm. fell on the 1st and 2nd, each day getting 20 mm.
The province as a whole was warmer than usual, with most areas 1-2C above normal. Likewise, most areas were drier. But there were exceptions during the violent thunderstorms that affected Toronto and Southwestern Ontario on the 2nd and 3rd. Many records were set – more than 100 mm. around Vaughan for example. U of T set a daily record of 59.5 mm. That’s a month’s worth in a few hours!
Mercifully, the gusty storms and a tornado on September 3rd passed well south of us but caused extensive damage in Essex and Kent counties.
Climate Change Canada is forecasting a continuing trend of warmer weather for October.
