September 2025 brought a classic Colorado blend to Boulder and the Front Range: near-normal temps, wetter-than-average skies, and a lively mix of sunshine and storms. A standout precipitation event around the 23rd delivered soaking rain in the lowlands and the first real coating of snow to the Mountains. The month eased us gently into autumn, with crisp mornings, comfortable afternoons, and brilliant foliage lighting up the higher terrain. And yes—who could forget that dramatic wave of Canadian wildfire smoke that swept through, reminding us how connected we are to the broader arid landscape of western North America. Here’s a quick and colorful graphical recap of our weather during September and how it relates to climatology.

September 2025 Temperatures:

2025 90-Degree Day Timeline:

September 2025 Precipitation:

Precipitation totals during September 2025 across the Boulder-Denver Metro area

September 2025 Snowfall:

Snowfall totals during September 2025 across the Boulder-Denver Metro area

2025-26 Seasonal Snowfall To Date:

You can find a recap of all the winter storms from the 2024-2025 snow season HERE.

How does September 2025 fit into the last 75 years?

How does September 2025 fit into the last 12 months?

Latest Drought Tracker (as of September 30th)

September 2025 retold via our Twitter X timeline:

NOTICE: We are now on Threads and Bluesky! Come follow us there, too!

Our top posts of September 2025

RELATED POST:
August 2025 Graphical Weather Review: A hot, dry & smoky month saved by a cool & rainy finish
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This Weekend in Colorado Weather: Trending somewhat cooler and wetter as a Pacific trough clips Colorado --- and yes there will be Mountain snow!
RELATED POST:
Colorado Forecast Update: Thursday evening's smoky front will usher in cooler, (slightly) wetter weather for the weekend
RELATED POST:
This Week in Colorado Weather: September 22, 2025
RELATED POST:
BoulderCAST Daily – Wed 09/24/25 | More than 1" of rain for everyone yesterday, but we dry out the rest of the week

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BoulderCAST Team

BoulderCAST Team

This post had major contributions from at least two members of our team. The more meteorologists the better, right?

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