In 10 days · Sat, Oct 17, 2026
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Saturday, October 17th, 2026
Boston Ave. between Main and Martin, Longmont CO
5K
37–64°F · low rain risk
See last 10 years
On this date: rain 0 of the last 10 years
2025
38–64°F
dry
2024
48–74°F
dry
2023
40–81°F
dry
2022
36–61°F
dry
2021
37–68°F
dry
2020
45–73°F
dry
2019
38–74°F
dry
2018
23–55°F
dry
2017
37–70°F
dry
2016
47–72°F
dry
Best months to race in Colorado →
Race-day forecast says layers
37°F at the start.
Gloves, ear warmers, throwaway layers, hand warmers — delivered before race day.
Race-day forecast · Saturday, Oct 17
Sunny · 37–65°F
Saturday, Oct 17starts near 37°F · 21% chance of rain · wind up to 15 mph
About this race
Something spooky this way runs! Lace up your monster clogs and join the Longmont Area Chamber of Commerce for the inaugural Longmonster Dash 5K & Costume Contest on Saturday, October 17, 2026.
Runners, walkers, and broom fliers of all paces are welcome to join the fun. Race for pumpkin trophies and age-group awards, or come dressed to impress for a chance to take home one of our witch trophies in categories like Best Overall, Best Family, Best Group, Spookiest Costume, and more. After you cross the finish line, stick around, if you dare, for our finish expo featuring local businesses and community organizations.
The race will be held at Dickens Farm Nature Area, located between Main St. and Martin St. on Boston Ave. Packet pickup begins at 7:30 AM, and the chip-timed 5K starts at 8:30 AM. Parking information and an event map will be sent before race day.
Whether you’re racing the clock, your fellow ghoul, or dressing to win, come be part of a frightfully fun morning of community and Longmont pride!
Course map
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