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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 3d

...Edmonton normally has a longer growing season than the other prairie cities.
Regina's first fall frost was September 6th (1 wk early) and Saskatoon's was September 25th (1 wk late).
Calgary's will be October 5th (2 wks late).
And so far Winnipeg is frost-free.
public.tableau.com/shared/4HYJX...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 3d

...around town, Stony Plain didn't drop below freezing last night, so its first fall frost will be October 5th.
The airport's was back on September 25th, about 2 weeks late.
Campsie's (100km NW) was on September 5th, which is right on their average.
public.tableau.com/shared/XXX99...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 3d

...2025's final spring frost on May 16th was a bit later than the average of May 5th.
With the October 4th fall frost that makes a total of 140 frost-free days, below our average of 146.
Recently 2024 went 174 days, and 2023 went 182 (2nd most on record).
public.tableau.com/shared/3SZ5R...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 3d

Edmonton's first fall frost of 2025 was October 4th.
The average is September 29th, so this was just a bit late.
Recently we had the two latest fall frosts on record, with October 22nd in 2023 and 23nd in 2022.
(2024 was fairly late on the 12th).
#yegwx #yeg
public.tableau.com/shared/TNJQM...

history of frosts for edmonton with 2025, 2023 & 2022 highlighted

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

Quite a few months have something similar, but for January the scale it is just massive, with a ~10°C shift since the mid-70s.
public.tableau.com/shared/BMB65...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...and that brings us to the end of our look back at September 2025 weather in Edmonton.
All of these charts are interactive dashboards with data for 17 Canadian cities, accessible at:
edmontonweathernerdery.blogspot.com/2025/09/sept...

September 2025 Review

Weather history for Edmonton Alberta, from a year-round active-commuter. Trends and records for the northernmost city of 1M people in North America.

edmontonweathernerdery.blogspot.com

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...for October, we average about 1~2 Highs of 20°C, but half of the time there are none.
October also averages 2 Highs below 0°C, and 14 freezing Lows.
And...7cm of snow on average, although 2021, 2022 & 2024 had none.
public.tableau.com/shared/SKFQW...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...across the country the biggest September storms were:
50mm in Regina
38mm & 23mm in Toronto
25mm in Quebec City
20mm in Charlottetown
public.tableau.com/shared/JWDZR...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...these are the precipitation totals for 2025 across the country.
Quebec City is still way out ahead with over 865mm.
Montréal & St. John's are over 700mm.
And like Edmonton, Calgary recorded basically no precipitation (0.4mm) in September.
public.tableau.com/shared/96J5H...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...on the other hand, no September precipitation also means no September snow.
The last time that we recorded September snow was September 28, 2019 in Stony Plain.
And September 2018 was also very snowy.
public.tableau.com/shared/7YT6P...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...Storms? What storms?
By September our big summer storm season is over, but we still average around 10 days with Precipitation.
But not in 2025.
public.tableau.com/shared/9ZQY7...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...by the end of September we average around 377mm of precipitation for the year.
The dry September means that Campsie and the airport are a bit below average around 350mm.
But Stony Plain is way down at 267mm, and Blatchford is down at 250mm.
public.tableau.com/views/Edmont...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...in September we average 32mm of precipitation, and 2025 was SUPER low.
The airport recorded 0.6mm, Blatchford got to 0.9mm, and Stony Plain had 1.5mm.
Campsie (100km NW) got up to 13.3mm, but that's still well below average.
public.tableau.com/shared/SP8W9...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...September 2025 another above-average month across the country.
Edmonton was at the top at 6.9°C warmer than the 20th century average. Victoria was at the bottom, at 0.4°C warmer than theirs.
public.tableau.com/shared/4F7J6...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...September 2025 was well above average, so it's a big orange bubble here.
The average High of 23.8°C was 6.9°C warmer than the 20th century average.
The average Low of 8.8°C was 4.2°C warmer.
public.tableau.com/shared/FMGG6...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...with 3 months left in 2025, its average temperature is currently our 5th warmest overall, at 2.1°C above the 20th century average.
That's due to a warm January (#13), May(#6), August (#5), and September (#1).
The Highs are #4 warmest, and Lows are #9.
public.tableau.com/shared/WN773...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...around town, the airport did get its first frost on September 25th, which is about 2 weeks later than its average.
And Campsie's September 5th frost was right on its average.
public.tableau.com/shared/ZW526...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...this shows Blatchford's history of early frosts, counting the 0°C Lows which occurred each year before October.
Right now we've gone 6 years without a September frost. The longest gap on record was 7 years from 1975-1981.
public.tableau.com/shared/MSJXT...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...so far 2025 has set 8 new daily record Highs. That's below 2024's 11, but above the 5 from 2021-2023.
And 2025 has 6 record warmest-Lows. That's more than a lot of years, but 2021-2024 all ranged from 10-15.
public.tableau.com/shared/GS3XT...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...September averages 6 Lows above 10°C, and 2025 had 13.
It also averages 1 below-freezing Low, but 2025 was frostfree.
The last time that Blatchford a September frost was back in 2019.
public.tableau.com/shared/MH6JN...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...September's Lows were also mostly well above average, but did include 6 below-average days.
But there were also 3 new daily records on the 14th, 17th & 18th.
public.tableau.com/shared/XGCJB...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...we're getting to the end of our hot days, and 2025 will likely end up with 14 30°C Highs, which ties 1961 for the 3rd most on record (behind only 2024 & 2021).
And 2025's 56 25°C Highs is the 5th most on record, and the most since 1961 (1898's record is 64).
public.tableau.com/shared/MJ3RM...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...September averages around 11 20°C Highs, and 2025 had...24? Yup, 24.
That included 12 25°C Highs, when we average 3.
No 30°C days, but it did have 3 29°C Highs on the 12th, 13th & 20th.
The coldest High was 15.9°C. September averages 8 Highs below 15°C.
public.tableau.com/shared/3NPKC...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...so September 2025 was warm, with only 1 High below average (just barely) on the 24th.
Most of the month was well above average, including 2 new daily records on the 13th and 20th.
public.tableau.com/shared/DBWYH...

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chris - sᴉɹɥɔ @yegwxnerdery.bsky.social · 7d

...since 2021 we've had:
- #1 May in 2023, #6 in 2025
- #1 June in 2021, #3 in 2023
- #1 July in 2024, #3 in 2023, #6 in 2022
- #1 August in 2022, #5 in 2025
- #1 September in 2025, #3 in 2022, #5 in 2024
- #1 October in 2022
- #1 December in 2023
public.tableau.com/shared/CWSD6...

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