Chiang Mai Half Marathon

Chiang Mai, Thailand · December 20, 2026·

64°·64° high·Calm·Dry

Weather

Chiang Mai Half Marathon race day weather

64°at start

71° high

Calm

Dry

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Comfortable temps

Starting at 64°F, heat will be a factor from the gun — go out conservative and stay on top of hydration. High humidity (88%) will make it harder to cool down through sweat — increase fluid intake accordingly.

Race day forecast available in 28 days

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Distance: 13.1mi

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About the Chiang Mai Half Marathon

The Chiang Mai Half Marathon runs 21.1 kilometers from Tha Phae Gate in the old city to the King Naresuan the Great Monument in Mae Rim District, north of Chiang Mai. The route passes Wat Rajamontean, Wat Lok Moli and Chang Phuak Gate, loops around the moat past Chiang Mai Gate and Suan Dok Gate, then heads out along Huay Kaew Road and the Nimman area. It continues past the convention center and the 700th Anniversary Stadium before following the bike lane to the finish. The course is flat, and it is a point-to-point route with free shuttles back to the gate.

Website

Race weekend

Sunday, December 20

3:00 AMMarathon (26.2 mi)

4:00 AMHalf Marathon (13.1 mi)

5:00 AM10K (6.2 mi)

5:20 AM3K Smile Run (1.9 mi)

Course Map

Chiang Mai Half Marathon FAQ

When is the 2026 Chiang Mai Half Marathon?

The 2026 Chiang Mai Half Marathon will be held on Sunday December 20, 2026.

What is the time limit for the Chiang Mai Half Marathon?

The time limit for the Chiang Mai Half Marathon is 3.5 hours.

What will the weather be like for the 2026 Chiang Mai Half Marathon?

The forecast calls for a high of 84°F and a low of 61°F with a 0% chance of rain. Check our detailed hourly forecast above for the best half marathon race plan.

What is the weather usually like for the Chiang Mai Half Marathon?

Over the 9 years racecast.io has race-day weather for (2016 to 2025), it averaged 66°F at the start and 66°F by a typical finish. It has not rained during race hours in any of those years.

What was the hottest Chiang Mai Half Marathon?

Of the 9 years on record, 2022 was the warmest, reaching 73°F during race hours. The coldest start was 2017, at 59°F.

What was the windiest Chiang Mai Half Marathon?

Of the 9 years on record, 2022 was the windiest, with wind averaging 10 mph during race hours. The calmest was 2019, at 0 mph.

Chiang Mai Half Marathon weather history

Based on 9 years of data

Avg Temp

65°F

L:64° H:66°

RunScore

Conditions

Rain Freq

0 of 9 yrs

Wind2mph

Dew61°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

Year	Low / High	Rain	Dew Point
2025 Chiang Mai Half Marathon Partly cloudy throughout the day. 2025	63°/64°	-	61°
2024 Chiang Mai Half Marathon Partly cloudy throughout the day. 2024	64°/64°	-	61°
2023 Chiang Mai Half Marathon Partly cloudy throughout the day. 2023	66°/68°	-	64°
2022 Chiang Mai Half Marathon Partly cloudy throughout the day. 2022	72°/73°	-	59°
2021 Chiang Mai Half Marathon Partly cloudy throughout the day. 2021	66°/68°	-	64°
2019 Chiang Mai Half Marathon Clear conditions throughout the day. 2019	61°/63°	-	60°
2018 Chiang Mai Half Marathon Partly cloudy throughout the day. 2018	63°/64°	-	63°
2017 Chiang Mai Half Marathon Clear conditions throughout the day. 2017	57°/59°	-	55°
2016 Chiang Mai Half Marathon Partly cloudy throughout the day. 2016	68°/68°	-	64°

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