Is it finally over? Have we finally reached the end of The Great Deepfreeze of December 2021-January 2022? Let's take a look at just how deep this deepfreeze was:
Comparing deepfreezes is a bit difficult, but the temperatures plunged on December 24th, and stayed cold until January 10th.
There was a blip in the middle, with a warmup on the night of January 1st and morning of January 2nd, before temperatures plunged again.
For the Highs temperatures, from December 24th to January 9th there were 9 days with the coldest Highs in 30 years.
The average High of -21.3°C was the 4th coldest on record, after 1950 (-22.8°C), 1965 (-23°C) and 1966 (-23.3°C).
For the Low temperatures there were 7 days with the coldest Highs in 30 years.
The average Low for December 24th to January 9th of -28.4°C was the 9th coldest on record.
1949-1950 has the record with -30.7°C.
Cold Highs In-a-Row
We had 4 Highs of -24°C in-a-row.
For recent years that ties 2008 and 2004, and the January 2020 deepfreeze went 5 days.
The record of 14 was set in 1936.
There was also a separate 3-day run of -24°C Highs at Christmas.
We had 7 Highs of -22°C in-a-row, and another 5 in-a-row two days later.
7 days is the most since 1972 had 9.
Recently 2020, 2004, 1998, 1996, 1984 and 1982 went 5 days.
The record of 16 is from 1969, 1936 and 1934.
Cold Highs Each Winter
By the end of the deepfreeze we had 4 Highs reach -25°C, which ties the winter of 2019-2020. That's the most since 1996-1997 had 7.
That included 2 Highs of -27°C, which ties 2019-2020. Recently 2003-2004 had 3.
So far we have had 12 Highs reach -22°C, which is the most since 1996-1997 had 15.
No other recent winters have had more than 5 of those.
Our 17 Highs of -18°C is also a lot, behind 18 in 2010-2011 and 25 in 1995-1996.
Cold Lows In-a-Row
From December 24th through January 10th we had 19 Lows in-a-row reach -17°C.
That ties February 2019.
A bit further back 1996 had 25, and 1982 had 30.
The record of 49 is from 1950.
Over the course of the deepfreeze we had 18 Lows in-a-row reach -18°C.
That's 3 more than February 2021's deepfreeze, but 1 shy of February 2019 which had 19.
A bit further back 1996 had 23, and 1982 had 29.
The record of 46 is from 1950.
We had 17 Lows in-a-row reach of -22°C.
That is three more than February 2019, and four more than February 2021.
That is the longest since 1996, which had 19.
The record of 28 is from 1969 & 1950.
We had 8 Lows in-a-row reach -28°C, and another 4-day streak a few days later.
8 days is the most since 1970 had 8. The record of 18 was set in 1936.
Since 1985 the longest that we had gone was 5 days.
And finally, we also had 2 Lows in-a-row reach 30°C.
Recently February 2021 went 3 days, and January 2020 went 4 (along with 1997, 1996, 1989 and 1982).
The record of 16 is from 1887.
Cold Lows Each Winter
So far this winter we have had 4 Lows reach -30°C, which ties 2019-2020 and 2018-2019.
We have had 13 Lows reach -28°C, which is the most since 1996-1997 with 16.
For -25°C Lows so far we have had 15, which is above the average of 11.
And we have had 23 Lows reach -20°C, which is just below the average for a winter.
(...but there's still plenty of winter left)
The Deepfreeze Season
Historically our season for -25°C Lows stretched from early-November to late-March.
In recent decades that has been mid-November to mid-March.
-20°C Lows used to stretch from mid-October to mid-April, but now usually stick to mid-November through late-March.
Another Epic Deepfreeze?
Are epic deepfreezes getting tiring?
From 1999-2018 the longest streak of -20°C Lows we had was 10, and most years went 6~8.
Now for each of the past 4 winters we've hit 11+ days, including 18 in 2019, and 17 this winter.
(1995-1997 were super-cold, "volcano" winters)
For comparison, while 10+ Lows of -20°C in-a-row is a lot for Edmonton (at least until the past 4 winters), in Regina and Winnipeg it's pretty typical to have a 10~18 day deepfreeze each winter.
This messy chart is just a way to compare our recent deepfreezes of 2021-2021, February 2021, and February 2019 to the 28-day streak from 1950.
Outlying Areas
For surrounding stations like the Airport, Stony Plain, St. Albert and Campsie the Highs ãveraged 0.5~1.5°C colder than Blatchford.
The Lows averaged 1~5°C colder, with some days reaching 8~10°C warmer downtown.
While Blatchford had 2 Lows of -30°C in-a-row, Stony Plain had 3, and the Airport and Campsie each had 8 (the longest since 1982 and 1996 respectively).
The Airport had 7 Lows of -32°C in-a-row, which is its most since 1969, and Campsie's 8 days was the most since 1954.
What about Calgary?
During the deepfreeze Calgary was cold too, but their Highs have averaged 3.8°C warmer than Edmonton, with the Lows 2°C warmer.
A bunch of Highs were 7~8°C warmer, but for the Lows there were only a few days with big gaps.
We also took a quick look at Calgary's big deepfreeze on twitter here:
Snowdepth
At the end of the deepfreeze the snowdepth at local stations is 40cm+, while the average for mid-January is about 18cm.
For other recent winters the snowdepth in January 2014 reached 45~50cm, and 2011 was 45~70cm depending on the station.
And that brings us to the end of our review of the latest epic deepfreeze of 2021-2022. If you want to see how we covered some other, recent deepfreezes:
No comments:
Post a Comment