Climate Comment: A Look Back at 2019 – A Wet Year

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Submitted by Bill Caulfeild-Browne

December was a warm month by historical standards, nearly two degrees above normal, guaranteeing a green Christmas. The warmest days were the 26th and 27th when the mercury stretched up to 6.9C. The coldest was just one week earlier when a temperature of -13.4C and winds gusting to 57 kms/hr combined to provide a wind chill of -24C. This was the day of the Christmas Bird Count and most self-respecting birds stayed deep in the forest.

Precipitation, a mix of rain and snow, was normal at 61 mm. Winds were well above normal at the start of the month, gusting from the east at 40+ kms/hr, but by the end of the month we were seeing mostly calm days as the wind came from the south.

Sunshine, always at a premium in December, was fairly evident. We had seven fully sunny days and four partly sunny. In fact there were a couple late in the month that almost resembled early spring!

Looking back at the whole year we find a mean temperature of 5.5C, half a degree below the long-term mean but within one standard deviation. In other words, it was just about normal. The winter months were pretty much on target, but spring was cold. Both May and June were well below normal at 2.4C below expectations. July recovered to normal but with very few hot days. The highest was 29.1C on the 19th and this turned out to be the highest of the year.

August was very slightly cooler than usual; September and October were just about normal. November was very cold, the coldest I have recorded, and remarkable because it was a reversal of the much warmer than usual Novembers we’ve been experiencing in the last decade. On the other hand, if you combine our cold November with our warm December, we’re pretty much in line with “normal”.

Perhaps the most significant feature of the year was precipitation. It was wet – over 1,027 mm. of wet. This makes it the third wettest year I have recorded, part of a string of watery years since 2013. The last seven years have seen an average rain/snowfall of 965 mm, whereas the average in the last century was 804 mm.

I don’t think it’s coincidence that January 2013 saw exceptionally low lake levels and that since then we have been building towards a new record for high lake levels. Given the trend I’m seeing – unless there’s a sudden reversal in precipitation – water levels will go even higher in 2020. But forecasting Mother Nature is never easy.

Happy New Year to you all, I hope 2020 brings you fair weather!