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RMRR September Trophy Series

Thornton, Colorado, United States

calendar_today 13 Sep, 2026

directions_run Running

sell $10.00

About the Event

Rocky Mountain Road Runners holds a monthly Trophy Series in the Denver area. We provide a low-key, low-cost racing environment. Everyone is welcome to run with us!

The 10km race uses a handicap start system, slow-to-fast, spread over ~30 minutes. This gives everyone a chance to win. We'll use your estimated finish time to assign you a start time with others the same speed.

All 5k racers will start ~15min after the first 10km starters.

Race Day Details

Time: 10k starts at 8:00 am + your handicap.*
5k starts approximately 15min after the first 10k starter.
Show up 30 minutes early to get your tag and warm up.
Location: Riverdale Ballfields, 9830 Riverdale Road, Thornton, Colorado, 80229
Course: Both distances are out-and-back on a mix of paved and smooth gravel.
Parking: Plenty of parking at the park.

* The Trophy Series races use a unique, handicap start and scoring system. 10k racers start from slow to fast giving everyone a chance to win. When you register and pick up your number, we'll help you choose an appropriate start time that fits your estimated time.

Races Offered

10k

Sep 13, 2026

straighten

Distance — 10K

terrain

Type — Running

timer

08:00

sell

$10.00

5k

Sep 13, 2026

straighten

Distance — 5K

terrain

Type — Running

timer

08:15

sell

$10.00

Weather History

These values represent the 3-year monthly averages for September in Thornton.

thermostat Temperature

11.6° / 27.5°

wb_sunny Feels like

9.1° / 24.1°

light_mode Avg sunshine hours

11h 7m

water_drop Avg rainfall

1.1 mm

ac_unit Avg snowfall

—

air Avg wind speed

8.9 km/h (Light breeze)

opacity Sweat loss rate

Moderate

terrain Course conditions

Firm and slightly soft

sunny Max UV Index

Moderate (5.0)

humidity_mid Humidity

45.1%

wb_twilight Sunrise

06:41

nightlight Sunset

19:06

About Thornton

Learn more about the host city, Thornton.

Thornton is a city of about 144,000 in the Denver Metropolitan Area of the western U.S. state of Colorado. The city lies northwest of Denver in Adams and Weld counties. It is a diverse community with a strong commitment to quality of life and environmental issues.