Runners will face a temperature rise from 64°F at the start to a peak of 83°F. With an average humidity of 82% and a dew point of 64°F, conditions will feel sticky. It is advisable to start conservatively and hydrate frequently to maintain performance 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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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 4 years of data

Avg Temp

74°F

L:58° H:74°

RunScore

Conditions

Rain Freq

0 of 4 yrs

Wind6mph

Dew57°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°/83°	-	64°
2024 South Texas International Marathon Partly cloudy throughout the day with early morning rain. 2024	51°/62°	-	52°
2023 South Texas International Marathon Clear conditions throughout the day. 2023	56°/74°	-	53°
2023 South Texas International Marathon Clearing in the afternoon. 2023	61°/76°	-	60°

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