Runners will face a starting temperature of 64°F, increasing to 87°F by the finish. Humidity levels will be high at 78%, making conditions feel warmer. With light winds and no rain expected, it's advisable to start conservatively and focus on hydration throughout the race.

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Distance: 26.2mi

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Race Info

South Texas International Marathon’s (STIM) unique course will take runners through four cities and two counties! This Boston Qualifier marathon will make its start at the “Heart of the Valley”, Donna, Texas. Runners will then cross through historic downtown areas of Weslaco, Mercedes and La Feria. The grand finish line will be at the Mercedes FEMA Dome in Mercedes, Texas. Source

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Race weekend

Sunday, December 7

6:30 AMMarathon (26.2 mi)

6:30 AM6-Person Relay (26.2 mi)

7:30 AMHalf Marathon (13.1 mi)

Course Map

FAQ

When is the 2025 South Texas International Marathon?

The 2025 South Texas International Marathon will be held on Sunday December 7, 2025.

Is the South Texas International Marathon a Boston Marathon Qualifier?

Yes, the South Texas International Marathon is an official Boston Marathon qualifier.

What is the time limit for the South Texas International Marathon?

The time limit for the South Texas International Marathon is 6.5 hours.

What will the weather be like for the 2025 South Texas International Marathon?

The forecast calls for a high of 89°F and a low of 64°F with a 0% chance of rain.

Historical Weather

Based on 3 years of data

Avg Temp

59°F

L:57° H:63°

RunScore

Conditions

Rain Freq

0 of 3 yrs

Wind4mph

Dew56°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

Year	Low / High	Rain	Dew Point
2025 South Texas International Marathon Partly cloudy throughout the day. 2025	64°/70°	-	63°
2024 South Texas International Marathon Partly cloudy throughout the day with early morning rain. 2024	51°/55°	-	50°
2023 South Texas International Marathon Clear conditions throughout the day. 2023	56°/64°	-	55°

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