Tuesday, December 1, 2009

November 2009 Summary

A very warm and dry month with the lowest snowfall ever (possibly, maybe?)

November started out with 6 colder than average days, however that changed when the rest of the month (24 days) all came in warmer than average. Overall it was an amazing 3 degrees above average making it the warmest November since 2001. It was also the most above average month since January of 2008.

It was also the driest month since 2001 with only 34.8 mm of precipitation including a dry stretch that lasted 12 days. Almost all of it came in the form of rain as we only recorded a single day with some trace snow (November 27th).

So now the big question: was this the least amount of snow ever in November for the region? Unfortunately, it is not an easy question to answer as it all depends on how you interpret the trace readings of snow you often get at this time of year. A trace amount of snow is when there is less than 0.5 cm but definitely some on the ground. There have been many years with less than 1 cm of snow in November, for instance in 2006 we only had 0.5 cm.

Looking back in the long term records the last time there was 0 cm of snow was back in 1963. However, the daily records show that there were 6 days with trace snow in 1963 and going back further I was never able to find a year with 0 cm of snow and less than 3 days of trace snow. So using that as a criterion we can say that this November had the least amount of snow of November in the recorded history of the region which goes back to 1914.

The total precipitation for the year (819.5 mm) is very close to the average (830.3 mm). So unless we get less than 15 mm or over 350 mm in December, this year will end up in the average range for precipitation.

Summary for November 2009:
Maximum Temperature 18.0 °C
Minimum Temperature -5.0 °C
Average Daily High Temperature 9.3 °C (Long term average 5.9 °C)
Average Daily Low Temperature 0.9 °C (Long term average -1.6 °C)
Total Precipitation 34.8 mm (Long term average 82.3 mm)

(Long term averages based on 1971-2000 data for the Waterloo Wellington Airport)

Sign up to get the monthly weather station summary by e-mail


Anonymous said...

This month was ridiculously warm! I sure hope the CO2 in the atmosphere keeps rising - we could use more months like this.

Matt said...

I was camping up near Tobermory during the weekend of the 21st, and it felt like late summer. It was something else - beautiful!