Wednesday, March 2, 2022

The cold winter of 2021-22 in Victoria

Meteorological winter is from December 1 to February 28.  Winter 2021-22 in Victoria was much colder than average.  It was also rainier and much snowier than average.  

This past winter was the coldest in the past 5 years, and the 4th coldest in the past 30 years.  The mean temperature at Victoria Gonzales was 4.6 degrees, which is 1.2 degrees colder than the 30-year average of 5.8.  The average daily maximum for winter 2021-22 was 6.7 degrees , while the average daily minimum was 2.5, both of which were 1.2 degrees colder than the 30-year averages of 7.9 max and 3.7 min.  December was the coldest month, with a mean of 2.9 degrees, making it the 9th coldest December in the past 124 years, and 2.7 degrees colder than the long term average.  While January and February were closer to average, both were about 0.5 degrees colder than normal.


The chart below shows the daily maximum and minimum temperatures at Victoria Gonzales during winter 2021-22, compared with the 30-year averages.  The temperature trend is distinguished by two arctic outbreaks, resulting in a major cold snap in late December, and a second less severe cold snap in late February.  The rest of the winter was fairly close to average.  The warmest day of the winter was recorded on the first day of the season, with a high of 12.7 C on December 1.  

Daily Max & Min Temps at Victoria, winter 2021-22


The December cold snap was one of the most severe in Victoria in recent memory.  The overnight minimum dropped as low as -9.7 C on December 27, which was Victoria's coldest recorded temperature in 36 years.  There were 4 consecutive days when the temperature did not rise above freezing, tied for the 7th longest such streak in the past 124 years in Victoria.  

Victoria Gonzales saw 14 days this winter with overnight lows below freezing, versus the long-term average of 9.6 days.  Eight of these days occurred consecutively, from Dec. 25 to Jan. 1, during the late December cold snap.  A further 5 days occurred consecutively during the late February cold snap.

Victoria received 302 mm of precipitation from December to February, 13% more than the normal winter precipitation of 267 mm.  December and January were both about 25% wetter than normal, but February was slightly drier than normal.  February would have been much drier than normal, if not for 36 mm of rain during the last two days of the month.  Up until Feb. 26, Victoria had received only about 15 mm of rain in February - about 25% of normal.  

Winter 2021-22 saw more days with measurable precipitation than the 30-year average.  There were 55 days with greater than 0.2 mm of precipitation versus the long term average of 46.4 days.  December saw 24 days with precipitation (versus the normal 16.8), January saw 18 days (close to the normal 16.6), and February saw 13 days (right on the normal 13.0 days).  There were also more heavy precipitation days during winter 2021-22 than normal: 5 days with more than 25 mm of precipitation vs. the long range average of 1.5 days.  


The chart below shows daily precipitation during winter 2021-22, and compares the cumulative precipitation with the 30-year average.  The winter was consistently wetter than average until about January 20.  This was followed by about 5 weeks with much drier than normal weather, then finally more heavy rain during the last 2 days of the season.   The wettest day of the winter was January 6, when 33.9 mm fell.  



Daily & Cumulative Precipitation in Victoria, winter 2021-22



The chart below compares the precipitation amounts in Victoria this winter with other locations in the region.  Thanks to the Olympic Mountain rainshadow, Victoria Gonzales is typically much drier than other locations in the region.  However, continuing a recent trend of the past couple of years, the differences were less than normal this winter.  Victoria had 113% of normal winter precipitation, while Victoria Airport had just 94% of normal and Vancouver had only 83% of normal.  Like Victoria, Seattle had above normal precipitation during winter 2021-22.  

  
Winter Precipitation in the Region, 2021-22



Victoria received 30 cm of  snow in winter 2021-22.  That's more than double the normal winter snowfall of 13.8 cm. Half of this winter's snow fell in December (16 cm), and most of the rest (12 cm) fell in January.  Victoria had 10 days this winter with at least 2 cm of snow on the ground.  That's 3 times the normal 3.2 days with snow on the ground.

Overall, winter 2021-22 was  close to normal for sunshine.  December and February were a bit sunnier than normal, while January was a bit cloudier than normal.

The table below shows the number of mostly sunny days (>80% of possible sunshine), partly cloudy days (20-80% of possible sunshine), and mostly cloudy days (<20% of possible sunshine) during winter 2021-22.  Overall, there were close to the normal amount of mostly sunny days, while there were more than average partly cloudy days, and fewer than average mostly cloudy days.  December had fewer than normal sunny days, but more partly cloudy days.  February had more than normal sunny days and fewer than normal mostly cloudy days.