Grasslands Trail Run Marathon

Decatur, TX, USA · March 20, 2027·

49°·58° high·Breezy·Dry

Weather

Race Day Weather

49°at start

66° high

Breezy

Dry

Your goal

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to see the forecast where you'll be

Cool start, warming trend ahead

Runners will face a temperature rise from 49°F to 66°F, with a light breeze coming from the SW at 12 mph. Humidity remains moderate at 50%, making hydration essential. As temperatures increase, participants should consider adjusting their pace and staying mindful of hydration to maintain performance.

Race day forecast available in 135 days

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Distance: 26.2mi

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Race Info

The Grasslands Trail Run is held on the Lyndon B. Johnson National Grasslands near Alvord, Texas, north of Fort Worth. Every distance starts and finishes at the TADRA Point Trailhead: the 100-mile, 50-mile, marathon and half marathon run on Saturday and the 15K on Sunday. The loops cross rolling hills, open pasture and pine and oak woods on single-track and equestrian trails shared with horses and cattle. The 100-mile course has about 4,000 feet of climbing. Source

Website

Race weekend

Saturday, March 20

5:00 AM100M (100.0 mi)6:00 AM50M (50.0 mi)

7:30 AMMarathon (26.2 mi)

8:30 AMHalf Marathon (13.1 mi)

Sunday, March 21

7:30 AM15K (9.3 mi)

Course Map

FAQ

When is the 2027 Grasslands Trail Run Marathon?

The 2027 Grasslands Trail Run Marathon will be held on Saturday March 20, 2027.

Is the Grasslands Trail Run Marathon a Boston Marathon Qualifier?

No, the Grasslands Trail Run Marathon is NOT a Boston Marathon qualifier.

What is the time limit for the Grasslands Trail Run Marathon?

The time limit for the Grasslands Trail Run Marathon is 16.5 hours.

What will the weather be like for the 2027 Grasslands Trail Run Marathon?

The forecast calls for a high of 72°F and a low of 51°F with a 9% chance of rain. Check our detailed hourly forecast above for the best marathon race plan.

Historical Weather

Based on 24 years of data

Avg Temp

53°F

L:49° H:58°

RunScore

Conditions

Rain Freq

13%

3 of 24 yrs

Wind7mph

Dew42°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

Year	Low / High	Rain	Dew Point
2026 Grasslands Trail Run Marathon Clear conditions throughout the day. 2026	57°/77°	-	53°
2025 Grasslands Trail Run Marathon Partly cloudy throughout the day. 2025	53°/59°	-	26°
2024 Grasslands Trail Run Marathon Partly cloudy throughout the day with rain. 2024	52°/57°	-	50°
2023 Grasslands Trail Run Marathon Clear conditions throughout the day. 2023	38°/43°	-	25°
2022 Grasslands Trail Run Marathon Clear conditions throughout the day. 2022	43°/61°	-	27°
2021 Grasslands Trail Run Marathon Clear conditions throughout the day. 2021	43°/56°	-	35°
2019 Grasslands Trail Run Marathon Clear conditions throughout the day. 2019	38°/51°	-	21°
2018 Grasslands Trail Run Marathon Clear conditions throughout the day. 2018	53°/60°	-	34°
2017 Grasslands Trail Run Marathon Clearing in the afternoon. 2017	60°/71°	-	61°
2016 Grasslands Trail Run Marathon Clear conditions throughout the day. 2016	37°/48°	-	29°
2015 Grasslands Trail Run Marathon Partly cloudy throughout the day with rain. 2015	50°/55°	-	50°
2014 Grasslands Trail Run Marathon Cloudy skies throughout the day. 2014	55°/59°	-	35°
2013 Grasslands Trail Run Marathon Cloudy skies throughout the day with rain. 2013	41°/46°	Light	43°
2012 Grasslands Trail Run Marathon Clear conditions throughout the day. 2012	51°/67°	-	47°
2011 Grasslands Trail Run Marathon Clear conditions throughout the day. 2011	63°/71°	-	59°
2010 Grasslands Trail Run Marathon Cloudy skies throughout the day with rain or snow clearing later. 2010	32°/35°	Light	31°
2009 Grasslands Trail Run Marathon Clear conditions throughout the day. 2009	56°/65°	-	50°
2008 Grasslands Trail Run Marathon Clear conditions throughout the day. 2008	42°/63°	-	34°
2007 Grasslands Trail Run Marathon Partly cloudy throughout the day. 2007	61°/65°	-	59°
2006 Grasslands Trail Run Marathon Clear conditions throughout the day. 2006	37°/54°	-	34°
2005 Grasslands Trail Run Marathon Partly cloudy throughout the day with a chance of rain throughout the day. 2005	46°/47°	Moderate	45°
2004 Grasslands Trail Run Marathon Partly cloudy throughout the day with late afternoon rain. 2004	69°/74°	-	65°
2003 Grasslands Trail Run Marathon Partly cloudy throughout the day with rain. 2003	47°/56°	-	46°
2001 Grasslands Trail Run Marathon Partly cloudy throughout the day with early morning rain. 2001	46°/62°	-	51°