Wednesday, January 5, 2022

2021 was a year of weather extremes in Victoria

2021 was an extraordinary year for weather in Victoria.  Below is a list of just some of the weather extremes experienced in 2021: 

  • All-time hottest temperature ever recorded: 39.8 C on June 28, shattering the old record by almost 4 degrees.
  • Warmest June on record, with mean temperature of 16.6 C.
  • Coldest temperature recorded in 36 years: -9.7 C on December 27.
  • Four consecutive days when the temperature did not rise above freezing (Dec. 26-29) – the longest stretch in 36 years.
  • Biggest range of temperatures ever recorded in one year: 49.5 degrees C.

  • The wettest year on record, with an estimated 953 mm of precipitation.  The old record was 944.6 mm in 1933.  
  • There were 8 days with 25 mm or more precipitation, the most ever recorded at Victoria Gonzales.
  • Wettest meteorological fall (Sept. 1 to Nov. 30), with 510 mm. The rainfall during those 3 months was equal to more than 80% of Victoria’s average annual rainfall.
  • Not one, but two of the 10 all-time wettest days ever recorded in Victoria: 72.6 mm on November 15 (7th wettest) and 71.4 mm on October 28 (9th wettest).
  • Tied for the driest July on record with 0 mm (there have been 6 other Julys with no rainfall).
  • 3rd longest streak with no measurable rain: 53 days from June 15 to August 6.

Truly amazing!

The mean temperature for 2021 (10.6 C) was close to the 30-year average of 10.7 C, but there was a lot of variation during the year.

Six months had higher than normal temperatures (January, April, June, July, August, and November).  June was the warmest on record (16.6 C - a full 2 degrees above normal), while the summer overall was the 6th warmest in 123 years.  On the other hand, six months were cooler than average (February, March, May, September, October, and December).  

The hottest temperature of 2021 - and the hottest temperature ever recorded in Victoria - was on June 28, with a temperature of 39.8 C.  That was about 20 degrees above the normal temperature for the date, and nearly 4 degrees hotter than the previous all-time temperature record for Victoria.  There were 3 days in 2021 with daily maximums above 30 C, compared with the normal of 1.1 days.  There were 15 days with daily maximums above 25 degrees, compared with the average of 9 days.    

The coldest temperature of 2021 was -9.7 C on December 27.  That was the coldest temperature recorded at Victoria Gonzales since November 1985 - more than 36 years.  There were 13 days in 2021 when the temperature went below 0, significantly higher than the long-term average of 9.5 days.  Of those days when temperatures dropped below freezing, 6 occurred consecutively in February, while the other 7 occurred consecutively at the end of December.  Victoria also saw 4 consecutive days when the temperature did nor rise above zero - the longest such stretch since November 1985.

The chart below shows the daily maximum and minimum temperatures at Victoria Gonzales in 2021, compared with the long-term normal temperatures.  The most prominent variations from normal were the heat wave in late June and the cold snap in late December.  As a result of these extreme events, Victoria Gonzales experienced its largest range of temperatures ever recorded in a single year in 2021 - a range of 49.5 degrees between the 39.8 C on June 28 and the -9.7 C on December 27.  The average temperature range in Victoria is about 35 degrees, while the old record was 45.6 degrees in 1968.




2021 was the wettest year on record at Victoria Gonzales, with an estimated 953 mm of precipitation, 45% more than the long-term average of 656 mm.  The old record was 944.6 mm in 1933.  The record rain in 2021 followed 2020, which at the time was the wettest year in 20 years in Victoria, with 837 mm.   The fall was especially wet, in fact it was the wettest fall on record in Victoria, with 510 mm of rain from September 1 to November 30.  Victoria saw 633 mm - an entire year's worth of precipitation - in the last 4 months of the year.

The chart below shows daily and cumulative precipitation at Victoria Gonzales for 2021.   It was really only in the last 4 months of the year that precipitation was much above average.  In fact, the summer was the 6th driest on record, with just 16 mm of rain from June 1 to September 30.  This included a 53-day streak with no measurable precipitation from June 15 to August 6 - the third longest dry streak on record in Victoria. 



There were 145 days with measurable precipitation in 2021, compared with the normal of 132 days.  There were two days in 2021 that were among the 10 wettest days ever recorded in Victoria: 72.6 mm on November 15 and 71.4 mm on October 28.  There were 8 days with more than 25 mm of rain in 2021, the most on record at the Victoria Gonzales location, and far higher than the average of 2.9 days annually.  

The chart below compares annual precipitation at Victoria Gonzales in 2021 with other locations in the region.  Thanks to its rainshadow location, Victoria is typically drier than most other locations, and while that was still the case in 2021, the difference was not as much as it usually is.  That's because precipitation at Victoria Gonzales was 45% above normal in 2021, while it was just 8% above normal at the Victoria Airport (in North Saanich) 4%  above normal in Vancouver, and 11% above normal in Seattle.  Looking at this another way, the Victoria Airport typically receives more than 36% more precipitation than Victoria Gonzales, but in 2021 it got just 1% more.


Comparison of Annual Precipitation in 2021

Victoria received 44 cm of snow in 2021, nearly triple the average of 16 cm.  2021 was the snowiest year in Victoria since 1996.  There was 28 cm of snow in February, and a further 16 cm in December.  There were 10 days in 2021 with at least 2 cm of snow on the ground, 4 in January and 6 in December.  That is nearly 3 times the annual average of 3.5 days with snow on the ground.


Sunshine was slightly above average in Victoria in 2021 thanks to above average sunshine in June and July, as well as in March and April.  On the other hand, the fall months were cloudier than normal.  

The table below shows the distribution of mostly sunny, partly cloudy, and mostly cloudy days in 2021. There were 123 mostly sunny days, slightly above the average of 121.  There were 139 partly cloudy days compared with the average 132 days.  Finally, there were 103 mostly cloudy days, fewer than the average of 113 days.



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