Okotoks Weather in September (1981–2025)

📍 50.73°N, 113.97°W •
📊

September at a Glance in Okotoks

(1981–2025)
Avg High
🔥
19.1°C
Avg Low
❄️
5.7°C
Avg Temp
🌡️
12.4°C
Avg Rain
🌧️
44 mm
Avg Humidity
💧
61%
Avg Wind
🌬️
1.2 m/s
Avg Solar
☀️
3.9
kWh/m²/day
vs Annual
📈
+7.2°C
temp difference
🌤️Mild afternoons❄️Cold mornings🌤️Fairly sunny🌦️Some rain🍃Light winds😊Comfortable humidity

Okotoks September Weather Overview

September is one of the warmer months of the year in Okotoks, with average highs near 19.1°C and lows around 5.7°C (mean 12.4°C). It is about average for rainfall, averaging 44 mm of rainfall and 61% relative humidity across the period.

Okotoks September Temperature History (1981–2025)

Range

September is one of the warmer months of the year in Okotoks. Across 45 years of records, the warmest September in Okotoks was 2025 — when the month averaged 16.7°C — while the coldest was 1985 at 6.9°C. Typical September days reach 19.1°C with nights near 5.7°C. The long-term trend is warming, about 0.7°C per decade.

1981–1985 vs 2021–2025

Avg Temp9.7°C→15.1°C+5.4°C
Max Temp15.9°C→21.8°C+5.9°C
Min Temp3.4°C→8.5°C+5.1°C

Trend (per decade)

Avg Temp+0.7°C/decade ↗
Max Temp+0.7°C/decade ↗
Min Temp+0.7°C/decade ↗

Distribution of Avg Temp

6.0°C–8.8°C4 yr (9%)
8.8°C–11.5°C12 yr (27%)
11.5°C–14.3°C16 yr (36%)
14.3°C–17.0°C13 yr (29%)

Okotoks September Rainfall History (1981–2025)

Range

September is about average for rainfall in Okotoks, averaging 44 mm of rainfall. The wettest September on record was 1985 with 122 mm, while the driest were 1990 and 1994 at 8 mm.

Okotoks September Humidity History (1981–2025)

Range

Relative humidity in Okotoks during September averages 61%. The most humid September was 1986 at 76%, and the least humid was 2009 at 47%.

Okotoks September Solar History (1981–2025)

Range

September receives about 3.9 kWh/m²/day of solar energy in Okotoks. The sunniest September was 1990 at 4.8 kWh/m²/day, and the cloudiest was 1986 at 2.9.

Okotoks September Wind History (1981–2025)

Range

Average wind speed in Okotoks during September is 1.2 m/s. The windiest September was 1985 at 1.4 m/s, while the calmest were 2008 and 2025 at 1 m/s.

What September Feels Like in Okotoks

🌅
Cold
Morning
🌞
Mild
Afternoon
🌆
Cold
Evening
Rain chanceModerate
Outdoor comfort★★★★☆

How September Ranks in Okotoks

🔥4th warmest month of the year
🌧️5th wettest month of the year
☀️6th sunniest month of the year

Ranked against the other 11 months using 1981–2025 averages.

Explore Okotoks Weather by Month

Okotoks September Averages by Decade

Metric1980s1990s2000s2010s2020sChange
Avg Temp10.6°C12.9°C12.4°C12.1°C14.9°C+4.3°C
Avg High17.0°C20.1°C19.2°C18.6°C21.6°C+4.6°C
Avg Low4.1°C5.6°C5.5°C5.6°C8.3°C+4.2°C
Avg Rain62 mm28 mm51 mm47 mm30 mm-32 mm

Extreme September Records in Okotoks

🔥Warmest September33.2°C1998
🧊Coldest September-8.1°C2019
🌧️Wettest September122 mm1985
🏜️Driest September8 mm1990
🌬️Windiest September1.4 m/s1985

Key Insights for September

✅

September temperatures in Okotoks have risen by about 5.4°C between 1981–1985 and 2021–2025.

✅

September has ranged from a record low of -8.1°C (2019) to a record high of 33.2°C (1998).

✅

Rainfall in September is about average for rainfall, averaging 44 mm, with a wettest year of 122 mm.

Is September a Good Time to Visit Okotoks?

One of the best times to visit Okotoks

September is one of the best times to visit Okotoks. Expect days averaging 19.1°C and nights around 5.7°C (mean 12.4°C) — warmer than Okotoks's yearly average — with moderate rainfall (44 mm), so conditions are generally comfortable for sightseeing and outdoor plans.

See Okotoks's complete weather history All 12 months side by side, 1981–2025 records, annual trends and long-term averages in one place. View full history →

Okotoks Weather in September — In Depth

☀️ September climate overview

September is one of the warmer months of the year in Okotoks, with average highs near 19.1°C and lows around 5.7°C (mean 12.4°C). It is about average for rainfall, averaging 44 mm of rainfall and 61% relative humidity across the period.

🌧️ Rain, humidity & wind in September

September averages 44 mm of rainfall in Okotoks, about average for rainfall compared with the rest of the year. The wettest September on record saw 122 mm (1985), and the driest just 8 mm (1990). Humidity sits around 61% and average wind speed is 1.2 m/s, with solar radiation averaging 3.9 kWh/m²/day.

📈 How September has changed

Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 5.4°C. Daytime highs moved from 15.9°C to 21.8°C and overnight lows from 3.4°C to 8.5°C over the same span.
September Weather in Okotoks, Year by Year
🔥 warmest❄️ coldest🌧️ wettest
YearAvg HighAvg TempAvg LowHottest DayColdest DayRainfallHumidityWindSolar
2025 🔥23.5°C16.7°C10.0°C29.5°C5.3°C17 mm64%1 m/s4.2
202421.3°C15.0°C8.8°C31.3°C1.7°C64 mm65%1.1 m/s4.1
202319.9°C13.7°C7.6°C28.6°C2.6°C35 mm63%1.1 m/s3.8
202222.7°C15.7°C8.8°C32.2°C1.2°C24 mm58%1.1 m/s4.1
202121.4°C14.3°C7.3°C28.2°C2.2°C12 mm54%1.2 m/s4.1
202020.9°C13.9°C7.0°C29.9°C0.1°C28 mm63%1.2 m/s3.7
201916.7°C11.3°C6.0°C26.4°C-8.1°C84 mm70%1.2 m/s3.5
201814.6°C8.7°C2.8°C27.7°C-5.1°C38 mm69%1.1 m/s3.1
201719.5°C12.6°C5.7°C30.9°C-0.5°C22 mm61%1.1 m/s3.8
201617.9°C11.7°C5.5°C25.0°C1.2°C46 mm66%1.2 m/s3.9
201518.0°C11.4°C4.8°C28.5°C0.2°C66 mm66%1.1 m/s3.9
201417.9°C11.7°C5.4°C27.5°C-8.0°C60 mm69%1.2 m/s3.8
201320.6°C14.2°C7.9°C30.2°C0.0°C58 mm62%1.2 m/s4.1
201222.6°C14.9°C7.3°C27.3°C1.3°C11 mm53%1.2 m/s4.3
201122.3°C14.7°C7.1°C29.4°C0.6°C25 mm55%1.3 m/s4.5
201016.1°C10.0°C3.9°C25.6°C-2.4°C56 mm72%1.1 m/s3.2
200924.0°C16.0°C7.9°C32.3°C1.1°C10 mm47%1.3 m/s4.5
200819.1°C12.1°C5.1°C27.7°C0.7°C56 mm63%1 m/s4.1
200718.0°C11.2°C4.4°C27.0°C-1.8°C50 mm63%1.1 m/s3.9
200619.9°C13.1°C6.4°C29.0°C-1.5°C48 mm62%1.2 m/s3.9
200516.7°C10.6°C4.5°C25.3°C-1.0°C98 mm69%1.1 m/s4
200417.4°C11.2°C4.9°C24.4°C-2.7°C40 mm70%1.1 m/s3.6
200319.0°C12.3°C5.5°C32.4°C-2.6°C52 mm59%1.2 m/s3.7
200217.1°C11.1°C5.0°C27.8°C-0.7°C87 mm66%1.2 m/s3.5
200121.9°C14.4°C6.8°C29.8°C3.2°C20 mm50%1.2 m/s4.1
200018.4°C11.7°C4.9°C28.3°C-6.7°C49 mm59%1.2 m/s3.8
199918.6°C11.7°C4.8°C27.6°C-3.0°C23 mm56%1.2 m/s4.3
199822.3°C14.8°C7.3°C33.2°C0.7°C26 mm55%1.2 m/s4.3
199722.0°C14.7°C7.4°C29.3°C-0.6°C17 mm56%1.2 m/s4.3
199616.0°C10.1°C4.2°C27.1°C-1.8°C59 mm65%1.3 m/s3.2
199520.2°C13.1°C6.0°C29.5°C-3.6°C20 mm56%1.1 m/s4.2
199423.2°C15.2°C7.2°C29.0°C0.8°C8 mm50%1.1 m/s4.3
199316.8°C10.3°C3.8°C26.4°C-1.8°C54 mm68%1.2 m/s4.3
199217.2°C10.1°C3.0°C27.4°C-4.1°C34 mm61%1.3 m/s3.7
199120.3°C12.9°C5.4°C28.2°C-0.7°C29 mm58%1.2 m/s4.3
199024.0°C15.7°C7.3°C30.6°C0.7°C8 mm50%1.2 m/s4.8
198919.4°C12.3°C5.3°C26.2°C-1.5°C44 mm61%1.2 m/s4.4
198819.4°C12.4°C5.4°C32.8°C-3.6°C40 mm57%1.3 m/s3.6
198722.1°C14.6°C7.1°C30.0°C2.7°C26 mm54%1.1 m/s4.2
198612.8°C7.6°C2.4°C24.1°C-1.1°C110 mm76%1.1 m/s2.9
1985 ❄️ 🌧️12.8°C6.9°C1.0°C21.2°C-6.0°C122 mm71%1.4 m/s3.4
198414.0°C8.1°C2.1°C26.9°C-6.4°C84 mm67%1.3 m/s3.7
198316.0°C9.6°C3.2°C27.2°C-4.3°C18 mm60%1.3 m/s—
198217.1°C11.0°C4.8°C28.1°C-4.0°C85 mm67%1.3 m/s—
198119.5°C12.7°C5.9°C31.2°C-2.4°C26 mm59%1.1 m/s—

Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.

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Okotoks September Weather — FAQ

What is the average temperature in Okotoks in September?▼

The average high in September is around 19.1°C with lows near 5.7°C (mean 12.4°C), based on 45 years of NASA POWER data.

Does it rain a lot in Okotoks in September?▼

September averages 44 mm of rainfall in Okotoks, about average for rainfall. The wettest on record was 122 mm in 1985.

What was the hottest September on record in Okotoks?▼

The hottest September reached 33.2°C in 1998. The coldest dipped to -8.1°C in 2019.

Has September in Okotoks gotten warmer over time?▼

Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 5.4°C. Daytime highs moved from 15.9°C to 21.8°C and overnight lows from 3.4°C to 8.5°C over the same span.

Is September a good time to visit Okotoks?▼

September is one of the warmer months of the year in Okotoks and about average for rainfall, so plan for around 19.1°C daytime highs and 5.7°C at night.

Is September the coldest month in Okotoks?▼

Not quite — September is the 9th coolest month in Okotoks, averaging 12.4°C.

What should I pack for Okotoks in September?▼

For September in Okotoks, pack warm layers and a jacket for chilly mornings, with typical highs of 19.1°C and lows of 5.7°C.

Is Okotoks humid in September?▼

Relative humidity in September averages 61% — moderately humid.

How windy is Okotoks in September?▼

Average wind speed in September is 1.2 m/s. The windiest September on record averaged 1.4 m/s (1985).

Which September had the most rainfall in Okotoks?▼

The wettest September on record was 1985 with 122 mm. On average, September sees 44 mm.

Where does this September weather data come from?▼

All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.

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Explore how the weather in Okotoks behaves each September, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for September specifically, along with year-by-year records and how the month has changed over the decades.