Monday, October 24, 2011

Longest frost free season ever seen

On the morning of October 23rd at 4:45 am the temperature went below zero for the first time since the spring.  It stayed below zero for almost 4 hours with the lowest temperature being -0.9°C.

The bigger news is that by my calculations the frost free season went from May 1st to October 22nd this year which is a total of 175 days.  This is the longest frost free season I have been able to find since records began in the region in 1915.  This year just beat out 1941 when they had a stretch of 174 days above zero. 

For full disclosure I just want to mention that there isn't enough data for 1937 and 1938 to be included in the analysis.

Thursday, October 20, 2011

Wettest day in over a year

The 51.6 mm of rain in the 24 hours between 8 am on the 19th and 20th was the single wettest day we have had since July 23rd, 2010 when we had 62.5 mm.

Thursday, October 6, 2011

September 2011 Summary

Another hot month with average precipitation

With an average temperature that was 1.8 degrees above average, September was the third hotter than average month in a row.  But it certainly wasn't consistent warm as the month was a battle between the cold arctic air masses and hotter air from the south.  As a result we saw some drastic temperature changes such as a high of 30.5 C on the third and then a high of only 15.5 C two days later.

The precipitation for September was within the average range (95.3 mm compared to an average of 87.5 mm) even though there were 17 days with some measured precipitation, which is more than the average of 12.  There were a couple of days with over 20 mm (the 19th and 27th) while the rest of it was was spread over many days with a bit of precipitation here and there.

The total precipitation at the end of September is 799.3 mm, which is still above the average of 680.7 mm for the end of the month.

Summary for September 2011:
Maximum Temperature 30.5°C
Minimum Temperature 3.5°C
Average Daily High Temperature 20.8°C (Long term average 20.0°C)
Average Daily Low Temperature 11.1°C (Long term average 8.3°C)
Total Precipitation 95.3 mm (Long term average 87.5 mm)

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