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After a Dry Spring, Banff’s July Rainfall Surged Past 30-Year Averages
Bow Valley Insider
August 05, 2025
July 2025 was one for the record books in Banff
The town saw nearly 100 millimetres of rain this past month, making it one of the wettest Julys in decades, according to Environment and Climate Change Canada. That deluge came after a relatively dry spring, setting up exactly the kind of conditions that lead to mudslides and slope failures, of which there were more than a few.
In early August, heavy rain triggered a mudslide in Kananaskis that closed Highway 40 and prompted safety advisories around Mist Mountain and Mount Lipsett. Another slide brought debris onto the Trans-Canada Highway just west of Banff near Redearth Creek, snarling long weekend traffic and briefly halting eastbound lanes.
Not the Wettest, But Close
Despite how it may have felt on the trail, or while sprinting from the car to the grocery store, July 2025 didn’t quite break historical records. Banff’s wettest July on record was back in 1927, and the infamous June 2013 flood month still reigns as the town’s single-wettest month in over 100 years.
Still, July 2025 wasn’t far off. It brought roughly 150% of Banff’s average July rainfall, based on 30 years of climate data. That kind of spike is rare, especially when preceded by two months of below-average precipitation. Banff received just 34 mm in May and 67 mm in June, both below the seasonal norms.
In other words, the ground was thirsty, until it wasn’t. And that rapid change likely contributed to the unstable conditions that followed.
Comparing Past Summers
To put this year into perspective, here’s how 2025 stacks up:
2021 was bone-dry. Banff saw just 22 mm in May and a paltry 39 mm in July—among the lowest in recent memory.
2016 was the last summer to rival this one for sheer wetness, with all three months (May–July) coming in above average and July topping 130 mm.
And then there’s 2013, the year most Bow Valley locals remember whether they want to or not. That June alone dumped over 160 mm of rain, causing catastrophic floods and reshaping riverbanks, trails, and emergency management plans across southern Alberta.
Banff Monthly Precipitation (May–July, 1995–2025)
All values in mm (rain + melted snow). 🔵 = much wetter than average, 🔴 = much drier than average.
Year | May (mm) | June (mm) | July (mm) |
|---|---|---|---|
1995 | 60 mm | 120 mm 🔵 | 90 mm 🔵 |
1996 | 45 mm | 78 mm | 65 mm |
1997 | 52 mm | 70 mm | 50 mm |
1998 | 40 mm | 85 mm | 72 mm |
1999 | 55 mm | 92 mm | 80 mm |
2000 | 30 mm 🔴 | 75 mm | 60 mm |
2001 | 38 mm | 60 mm 🔴 | 40 mm 🔴 |
2002 | 50 mm | 88 mm | 55 mm |
2003 | 42 mm | 65 mm | 18 mm 🔴 |
2004 | 48 mm | 72 mm | 45 mm |
2005 | 47 mm | 105 mm 🔵 | 70 mm |
2006 | 62 mm 🔵 | 80 mm | 64 mm |
2007 | 29 mm 🔴 | 66 mm | 58 mm |
2008 | 51 mm | 90 mm | 77 mm |
2009 | 35 mm | 81 mm | 63 mm |
2010 | 49 mm | 95 mm | 67 mm |
2011 | 72 mm 🔵 | 88 mm | 52 mm |
2012 | 44 mm | 70 mm | 46 mm |
2013 | 57 mm | 160 mm 🔵 | 36 mm 🔴 |
2014 | 37 mm | 75 mm | 61 mm |
2015 | 25 mm 🔴 | 69 mm | 42 mm |
2016 | 80 mm 🔵 | 110 mm 🔵 | 130 mm 🔵 |
2017 | 30 mm 🔴 | 55 mm 🔴 | 62 mm |
2018 | 41 mm | 60 mm | 75 mm |
2019 | 65 mm 🔵 | 98 mm | 89 mm 🔵 |
2020 | 28 mm 🔴 | 77 mm | 44 mm |
2021 | 22 mm 🔴 | 50 mm 🔴 | 39 mm 🔴 |
2022 | 30 mm 🔴 | 58 mm | 45 mm |
2023 | 55 mm | 62 mm | 90 mm 🔵 |
2025 | 34 mm | 67 mm | 99 mm 🔵 |
A Wetter Pattern—or Just a Weird One?
The big question now is whether this is just a statistical blip or part of a broader pattern. While one wet month doesn't make a trend, climate scientists are increasingly pointing to a rise in precipitation volatility, meaning sharper swings between dry and wet periods.
Banff’s climate record does support that. Over the last 30 years, the town has experienced more dramatic year-to-year shifts, including record drought in 2021, a wetter-than-normal 2023, and now a July 2025 that made locals dust off their rain boots and rethink that hike up Tunnel Mountain.
What It Means for the Bow Valley
From a community standpoint, these precipitation extremes have consequences. Heavy rains increase the risk of saturated soil, runoff, and landslides, especially when they arrive suddenly after dry spells. That’s particularly relevant in a mountain town surrounded by steep slopes, fast-moving creeks, and narrow valley infrastructure.
In recent weeks, Parks Canada and Alberta Parks have issued multiple warnings and closures due to trail washouts, unstable terrain, and active slide zones. It’s a reminder that even when Banff’s downtown stays dry, the hills above may be shifting.
So no, this wasn’t the wettest summer Banff has ever had, but it was wet enough to make a mess, close roads, and raise eyebrows. And with climate patterns looking less predictable by the year, it’s possible that the “new normal” for Banff might just be anything but.
What Do You Think?
Let us know in the comments!
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