Runners will face a temperature increase from 57°F at the start to a high of 90°F. Winds will be a headwind throughout, peaking at 12 mph with gusts up to 20 mph. With humidity at 56%, it's advisable for runners to start conservatively and adjust their pace in the warmer sections of the race.
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Distance: 26.2mi
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Common Goals:
The Grasslands Trail Run is held in the Lyndon B. Johnson National Grasslands, more than 20,000 acres managed by the U.S. Forest Service and situated north of Fort Worth. The trails loop among rolling hills and through a mixture of pine and oak grove forests, open fields, and livestock. Run the 100-Mile, 50-Mile, Marathon, Half marathon (Saturday Start) or 15K (Sunday Start) and enjoy the beauty of the Grasslands while sharing the trails with horses and running past cows—don’t let the cows out!Source
Course Map
FAQ
When is the 2026 Grasslands Trail Run Marathon?
The 2026 Grasslands Trail Run Marathon will be held on Saturday March 21, 2026.
Is the Grasslands Trail Run Marathon a Boston Marathon Qualifier?
No, the Grasslands Trail Run Marathon is NOT a Boston Marathon qualifier.
What will the weather be like for the 2026 Grasslands Trail Run Marathon?
The forecast calls for a high of 93°F and a low of 56°F with a 0% chance of rain. Check our detailed hourly forecast above for the best marathon race plan.
Historical Weather
Based on 23 years of data
Avg Temp
63°F
L:48° H:63°
RunScore
Conditions
Rain Freq
22%
5 of 23 yrs
Wind10mph
Dew42°F
Temperature History
Range of temperatures during race hours for each year.
