11th Annual BoulderCAST First Snowfall Contest
Ready to toss that first snowball of the season? Maybe you’ve already waxed your skis, shelled out for that pricey Epic Pass, or jumped the gun on snow tires (again). Well, hold onto your mittens—Boulder’s first big snow could be just around the corner, or not! Mother Nature has been playing tricks on us lately. In the past five years alone, we’ve seen both the earliest and latest first snows on record. But, what will 2025 bring? That’s where you come in.
We’re kicking off our annual First Snow Contest! Please take a look at Boulder’s snowfall history within, then submit your best guess for when the first measurable snow (≥0.1″) will fall in Boulder—and how much will accumulate. The closest guesses will win a selection of prizes!
*This contest is now closed to entries*
Boulder’s First Snow: A Climatological Snapshot
The chart below shows the date of Boulder’s first measurable snowfall for each year dating back to 1948. Measurable means that officially 0.1″ or more of snow was recorded. As is often the case early in the snow season, a few flakes mix in with rain, or flurries briefly fly, but never stick to the ground. These are instances where a trace of snow has occurred, but wasn’t measurable. For the purposes of the contest, we don’t care about these non-measurable snowflakes. We want actual accumulation! You can see there is a huge variation from year-to-year in the date of our first measurable snowfall. The earliest was September 8, 2020, with 1.7″ of snow falling. The latest measurable snow was November 17th of 2016 and 2021. That’s a spread of two and a half months! The normal (median) date of our first snow is October 20th.
Here’s how the odds stack up for first snow dates:
- On or before September 21st: 10%
- On or before October 4th: 25%
- On or before October 20th: 50% (MEDIAN)
- On or before October 31st: 75%
- On or before November 12th: 90%
Historically, Boulder sees its first measurable snow in:
- September: 22% of years
- October: 53% of years
- November: 25% of years
And while climate change is reshaping many seasonal norms, Boulder’s first snow trend—though not statistically significant—is nudging earlier. Something to consider when placing your bet!
How Much “First Snow” Typically Falls?
Our first snow is usually just a teaser—more of a frosty hello than a full-on blizzard. Between 1950 and 2017:
- 54% of first snows were under 2.0″
- Only 12% of first snowstorms topped 6.0″
- Average first snow: 3.0″
- Median: 2.0″
Boulder’s Recent First Snows: A Quick Recap
As mentioned earlier, Mother Nature has been throwing huge wrenches into our annual “first snow” contest constantly over the last few years. Here’s just a quick reminder on how our first accumulating snowfall went down over the last six years…
2019 – October 10th (3.8″)
Our inaugural accumulating snow in 2019 occurred on October 10th alongside an Arctic Blast surging into the center of the country. The frontal passage in our area was followed by 2 to 3 hours of heavy jet-forced snow bands. Boulder officially recorded 3.8″ of snow from these bands.
GOES-East infrared satellite animation from Wednesday morning (9/9/20)
Temperatures also dropped like a rock accompanying this first snow. Denver plummeted nearly 70 degrees in just 18 hours, from the 80s one day into the record-setting teens by the following morning. Needless to say, the 2019 growing season came to a rather abrupt end.
GOES-East infrared satellite animation from Wednesday morning (9/9/20)
2020 – September 8th (1.7″ on first day, 5.7″ storm total; earliest first snow on record)
In 2020, we had our earliest accumulating snowfall on record in Boulder on September 8th — before the first snow contest was even announced that year! This led to an unprecedented “second” snowfall contest taking shape. The first snow record was just one of many obliterated during the highly anomalous Great Labor Day Snowstorm of 2020 in the Front Range!
GOES-East infrared satellite animation from Wednesday morning (9/9/20)
2021 – November 17th (0.3″, tied for latest first snow on record)
In 2021, the summer and autumn season both were extremely warm and dry in our area. Boulder ended up tying for its latest ever first snowfall on November 17th — a measly 0.3″ that only accumulated on grassy surfaces following several hours of very light snow overnight. This historically delayed first snow resulted in all of the contest participants being way off. The person who guessed the latest date won the contest by default. After that crazy late first snow, there was only another inch of additional white stuff that fell over the next five weeks which further primed the dry prairie grasses in the lead up to the Marshall Fire tragedy in late December 2021.
2022 – October 27th (0.1″)
The first snow in 2022 was a bit of a disappointment with a rain/snow mix occurring during the daytime hours on October 27th. Boulder recorded an absolutely bare minimum first snow with only a dusting sticking on the grass, and that was only in SOME parts of town as temperatures were mostly above freezing. This led to a lot of confusion when we announced that the contest was over, as some people never even saw a snowflake in their location!
Snow only accumulating on the “cooler” parts of Boulder. In most cases, this was the slightly higher western areas, but also in the grasses. Credit: NWS
2023 – October 28th (0.6″ first day, 6.8″ storm total)
2023 was the most normally-timed first snow for us in recent memory, unfolding only about a week later than usual. However, this first dumping was on the larger side as a cluster of well-forecasted jet-forced snow bands targeted the Denver Metro area with heavy snow for several hours. When it was all said and done, most Front Range cities picked up between 5 and 10″ of snow. Boulder officially recorded a two-day storm total of 6.8″.
2024 – November 4th (0.2″)
Last year’s first snow was definitely underwhelming. A messy storm system brought more than half an inch of chilly rain to the city which briefly changed to snow overnight as temperatures dropped to ~33° for a few hours.
Temperature graph from the 11/4/2024 first snow event in Boulder. Snow was observed in the blue highlighted timeframe, just briefly overnight.
A light dusting of snow accumulated on the grass and trees in Boulder (officially 0.2″), but in some areas it completely melted before sunrise, once again causing some confusion for first snow contest entrants!
View looking west from Boulder on November 4, 2024 of the rain/snow line on Flagstaff Mountain
Enter our 2025 First Snow Contest!
So, what’s your best guess for 2025? Will it be an early October surprise or a November nail-biter? Will we get a sloppy dusting or a hefty dump? Let the snow games begin! ⛄
This is a community poll for the date you think the first MEASURABLE snowfall will occur in Boulder. Those who come closest to the actual date are the winners. For verification, we’ll go off the official Boulder climate station located at the NIST building in south Boulder (FYI, they follow UTC time for date cut-offs — roughly 5PM to 5PM local time). To be crystal clear, if our first snow event crosses over a calendar break, only the first day’s snow amount will count.
For prizes, we’re giving away BoulderCAST Premium subscriptions and Amazon Gift Cards. Among many perks, Premium members get full-access to our daily forecast discussion every morning. This is especially useful in the winter, when our meteorologists brain-dump thoughts for days leading up to impactful snowstorms. In case you weren’t with us over the last ten winters, we tend to do very well for the entire Denver Metro area (2015-2016 Recap / 2016-2017 Recap / 2017-2018 Recap / 2018-2019 Recap / 2019-2020 Recap | 2020-2021 Recap | 2021-2022 Recap | 2022-2023 Recap | 2023-2024 Recap | 2024-2025 Recap). Premium members also have admittance to our full suite of weather model graphics, complete 6-day hiking and 6-day ski forecasts, smoke forecasts, plus have exclusive access to some content such as video forecasts and weather quizzes.
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The prizes for the contest are as follows:
- 1st place: 12-month Premium subscription + $35 Amazon Gift Card
- 2nd place: 6-month Premium subscription + $15 Amazon Gift Card
- Anyone who guesses within 1 day OR 0.1″ correct: 2-month Premium subscription
- All other entries: Virtual “pat on the back”
IMPORTANT: In the event that multiple participants select the same winning date (they definitely will), the tie-breaker of snowfall amount will be used.
To get things started, here are the dates that some of the BoulderCAST Team has placed their bets on for our first snow:
- Andrew: October 18th – 4.0″
- Ben: October 29th – 2.5″
- Josh: November 4th – 2.0″
- Keah: November 9th – 3.0″
- Matt: November 23rd – 4.0″
Enter you NAME, EMAIL, and guesses for DATE and AMOUNT in the form below on or before Tuesday October 7th, 2024. Please only one entry per person.
❄️ 2025 FIRST SNOW CONTEST ENTRY FORM ❄️
*This contest is now closed to entries*
Prizes and recognition will be awarded in the days following our first dumping of snow. Let’s hope it’s a big one — good luck!
Photo taken along Trail Ridge Road in Rocky Mountain National Park, May 2019
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