The 2025 event has concluded.

South Texas International Marathon

Donna, TX, USA · December 7, 2025
partly-cloudy-day64°·83° high·Light·Dry
8
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Race Day Weather

partly-cloudy-day
64°at start
88° high
Breezy
Dry

Warm start, hydrate early

Runners will face temperatures rising from 64°F to a warm 87°F. The wind will be light at 8 mph from the WSW, with humidity high at 77% and a dew point of 64°F. It's crucial for runners to start conservatively and hydrate frequently to maintain performance throughout the race.

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clear-day8
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Distance: 26.2mi
0:00:00
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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

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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
74°F
L:59° H:74°
RunScore
8
Conditions
Rain Freq
0%
0 of 3 yrs
Wind8mph
Dew61°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

YearConditionsLow / HighRainScore

2025 South Texas International Marathon

Partly cloudy throughout the day.

2025
partly-cloudy-night
64°/83°-
8

2024 South Texas International Marathon

Partly cloudy throughout the day with early morning rain.

2024
cloudy
51°/62°-
9

2023 South Texas International Marathon

Clearing in the afternoon.

2023
partly-cloudy-night
61°/76°-
8

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