Drone view of Chemainus looking toward Beach Drive, Chemainus Secondary School and Daniel Street during a December dusting of snow. (Photo by Shawn Wagar)

Drone view of Chemainus looking toward Beach Drive, Chemainus Secondary School and Daniel Street during a December dusting of snow. (Photo by Shawn Wagar)

La Nina a force in December weather pattern

Snowfall far surpasses the normal for the month, but precipitation balances out with less rain

The weather in 2021 could only be termed interesting and ended with December following suit.

“The month started unseasonably mild, but temperatures quickly dropped to about two Celsius below normal which indicates a strong La Nina as originally expected,” noted Chris Carss, who compiles statistical information for Environment and Climate Change Canada at his Chemainus home.

Temperatures over the past six months have seen one example of extreme weather followed by another, he added. The heat dome in the summer and this winter’s very cold temperatures couldn’t be more opposite and then there was the July precipitation shutout matched against November’s heavy rains from an atmospheric river and flooding.

December was also a seasonally wet month overall, Carss indicated, “but rainfall actually was well below normal because most precipitation was in the form of snow, of which we had about three times our December normal.

“The rain and snowfall anomalies cancelled each other out to give us near normal combined precipitation.”

Other points of interest for December were: dry days with sunshine came out about a day less than normal; and there was a larger discrepancy in overall days with mostly or partly sunny conditions, with or without precipitation, falling below 20 days for the first time since Carss began reporting the statistic.

“It’s not a value recognized by Environment Canada or the World Meteorological Organization, but a monthly total I now believe is important on the west coast where we get a lot of days with mixed weather which tend to be counted only as wet weather days which can exaggerate our representation for having gloomy weather,” Carss added.

Facts and figures for December 2021 were as follows:

* Mean maximum temperature 4.5 C (normal 6.4 C).

* Mean minimum temperature 0 C (normal 2.4 C).

* Extreme maximum temperature 15.0 C on Dec. 1.

* Extreme minimum temperature -8.5 C on Dec. 27.

* Days of mostly or partly sunny and dry conditions 4 (normal 5).

* Days with precipitation and cloudy or partly sunny conditions 25 (normal 21).

* Total rainfall 171.8 millimetres (normal 226.9 mm).

* Total snowfall 62.4 centimetres (normal 19.4 cm).

* Combined precipitation 234.2 mm (slightly below the normal of 246.3 mm).

* Days mostly cloudy and dry 2.

* Days mostly or partly sunny, with or without precipitation, 18.

For comparisons, here are some statistics from December of 2020:

* Mean maximum temperature 7.6 C.

* Mean minimum 3.5 C.

* Extreme maximum temperature 12.5 C on Dec. 9.

* Extreme minimum -1.5 C on Dec. 24.

* Days mostly or partly sunny 7.

* Days mostly cloudy 24, of which 20 had precipitation.

* Total rainfall 307.6 mm (normal 226.9 mm).

* Total snowfall 13.2 cm (normal 19.4 cm).

On Thetis Island, Keith Rush recorded 170.6 mm of precipitation at his Foster Point Road residence that included 41.9 cm of snow.

December 2020 had 250.1 mm and the average December yields 158.1 mm of precipitation.

The yearly total for 2021 came out at 1,268.1 mm on Thetis, the third wettest since Rush has been keeping records over 13 years. The wettest year was 2016 with 1,359.2 mm.

As for the outlook for remainder of January, Carss foresees a continuation of La Nina conditions with below normal temperatures and above normal precipitation most of the time.

“Discrepancies might not be as great as last month, and storms might not be as powerful, but there will likely be some rough days ahead all the same,” he pointed out.

SnowWeather

 

Cool view from a drone toward Kin Park in Chemainus and the surrounding area during a December dusting of snow. (Photo by Shawn Wagar)

Cool view from a drone toward Kin Park in Chemainus and the surrounding area during a December dusting of snow. (Photo by Shawn Wagar)