The fifth wettest May on record, above average overall temperature, and the wettest ever start to the year
First off, how about that warm May! Hard to believe I know, but the daily low temperatures were a whopping 2.9 degrees above average for the month, this more than offset the daily highs that were 0.7 degrees below average. This means it was a little more than 1 degree above average overall for the month.
But of course people are going to remember the 4th when the high was only 7.0°C (the coldest daytime high in May since May 3rd, 2005) and the 16th when it only got up to 8.3°C.
One reason for the warmer than average nights was the amount of cloud cover we had during the month and the 17 days with some precipitation compared to an average of only 12, leading to...
The fifth wettest May since records began in the area at 150.3 mm, this actually ties us with May of 2000, but not close to the record back in 1956 when we had 202.2 mm. Just like April the first half of the month was very dry and it was the second half that put us well above average.
With the total precipitation for the year at 541.6 mm, not only is it well above the average (337.7) but it also way above the record which was 488.5 mm back in 1943.
Looking back now, it looks like April 30th will be the last frost day of the spring which is the earliest last frost date since 1999 when it was April 29th.
Summary for May 2011:
Maximum Temperature 31.1°C
Minimum Temperature 1.6°C
Average Daily High Temperature 18.2°C (Long term average 18.9°C)
Average Daily Low Temperature 9.4°C (Long term average 6.6°C)
Total Precipitation 150.3 mm (Long term average 75.7 mm)
(Long term averages based on 1971-2000 data for the Waterloo Wellington Airport)