Climate Comment for April 2021: A Weird Month!

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Submitted by Bill Caulfeild-Browne

Usually April is a month of rising temperatures as the sun gradually overcomes winter’s grip. This year was quite the opposite – the first half of the month was distinctly warmer than the second half. Overall, the mean temperature was 5.2C, which is 1.5C above normal. But all the warmth came in the first two weeks. From the 4th to the 14th our high temperatures were in the teens with the 8th reaching 20.9C. This would not be repeated in the second half where only five days even got into double digits. The only logical statistic was that our coldest temperature, -6.6C, did occur on the first of the month. 

Precipitation was 59 mm, just a tad drier than the average of 64 mm. Much of the rain, 25 mm, accompanied a violent thunderstorm on the 6th. That storm seemed to hang over Tobermory for several hours, on and off. A further 15 mm. fell on the 28th, a dreary rainy day but no doubt welcome to gardeners and farmers. On the 20th we had a trace of snow but the amount of moisture was too small to measure. It is quite rare that April had no snowstorm here – though Hamilton got blanketed on the 19th and 20th, setting a new record.

Our weather on the Peninsula was consistent with most of Ontario, which saw temperature anomalies as much as +3C. The mild spell I mentioned above broke several single-day records across the Province. Precipitation was highest around Lake Superior where twice the normal amount fell in some areas to the west. This may have consequences for our lake levels which have fallen so precipitously this year, but that’s far from certain.

May has started out very cold and the 14 day forecast shows little relief. After such a mild winter we may be seeing a reversion to the mean.

Stay safe!