Miramichi Weather in September (1981–2025)

📍 47.02°N, 65.51°W •
📊

September at a Glance in Miramichi

(1981–2025)
Avg High
🔥
19.9°C
Avg Low
❄️
9.1°C
Avg Temp
🌡️
14.5°C
Avg Rain
🌧️
70 mm
Avg Humidity
💧
77%
Avg Wind
🌬️
0.3 m/s
Avg Solar
☀️
3.7
kWh/m²/day
vs Annual
📈
+9.7°C
temp difference
🌤️Mild afternoons❄️Cold mornings🌤️Fairly sunny🌧️Wet month🍃Light winds💦Humid air

Miramichi September Weather Overview

September is one of the warmer months of the year in Miramichi, with average highs near 19.9°C and lows around 9.1°C (mean 14.5°C). It is about average for rainfall, averaging 70 mm of rainfall and 77% relative humidity across the period.

Miramichi September Temperature History (1981–2025)

Range

September is one of the warmer months of the year in Miramichi. Across 45 years of records, the warmest September in Miramichi was 1999 — when the month averaged 17.7°C — while the coldest was 1986 at 10.6°C. Typical September days reach 19.9°C with nights near 9.1°C. The long-term trend is warming, about 0.8°C per decade.

1981–1985 vs 2021–2025

Avg Temp13.4°C→16.5°C+3.1°C
Max Temp18.5°C→22.2°C+3.7°C
Min Temp8.3°C→10.8°C+2.5°C

Trend (per decade)

Avg Temp+0.8°C/decade ↗
Max Temp+1°C/decade ↗
Min Temp+0.6°C/decade ↗

Distribution of Avg Temp

10.0°C–12.0°C1 yr (2%)
12.0°C–14.0°C16 yr (36%)
14.0°C–16.0°C20 yr (44%)
16.0°C–18.0°C8 yr (18%)

Miramichi September Rainfall History (1981–2025)

Range

September is about average for rainfall in Miramichi, averaging 70 mm of rainfall. The wettest September on record was 1999 with 173 mm, while the driest was 2025 at 23 mm.

Miramichi September Humidity History (1981–2025)

Range

Relative humidity in Miramichi during September averages 77%. The most humid September was 1982 at 86%, and the least humid was 2025 at 67%.

Miramichi September Solar History (1981–2025)

Range

September receives about 3.7 kWh/m²/day of solar energy in Miramichi. The sunniest Septembers were 2009 and 2025 at 4.3 kWh/m²/day, and the cloudiest was 2010 at 3.1.

Miramichi September Wind History (1981–2025)

Range

Average wind speed in Miramichi during September is 0.3 m/s. The windiest Septembers were 2020, 2021 and 2022, among others at 0.4 m/s, while the calmest were 2023, 2024 and 2025, among others at 0.3 m/s.

What September Feels Like in Miramichi

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

How September Ranks in Miramichi

🔥4th warmest month of the year
🌵5th driest month of the year
☀️6th sunniest month of the year

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

Explore Miramichi Weather by Month

Miramichi September Averages by Decade

Metric1980s1990s2000s2010s2020sChange
Avg Temp12.9°C14.0°C14.6°C15.1°C16.3°C+3.4°C
Avg High18.0°C19.4°C20.2°C20.6°C22.0°C+4°C
Avg Low7.9°C8.6°C9.1°C9.7°C10.5°C+2.6°C
Avg Rain81 mm75 mm70 mm69 mm48 mm-32 mm

Extreme September Records in Miramichi

🔥Warmest September33.0°C2010
🧊Coldest September-1.1°C1989
🌧️Wettest September173 mm1999
🏜️Driest September23 mm2025
🌬️Windiest September0.4 m/s1981

Key Insights for September

✅

September temperatures in Miramichi have risen by about 3.1°C between 1981–1985 and 2021–2025.

✅

September has ranged from a record low of -1.1°C (1989) to a record high of 33°C (2010).

✅

Rainfall in September is about average for rainfall, averaging 70 mm, with a wettest year of 173 mm.

✅

Daytime highs and overnight lows have shifted differently — highs rose about 1°C per decade while lows rose 0.6°C per decade, widening the gap between day and night.

Is September a Good Time to Visit Miramichi?

One of the best times to visit Miramichi

September is one of the best times to visit Miramichi. Expect days averaging 19.9°C and nights around 9.1°C (mean 14.5°C) — warmer than Miramichi's yearly average — with moderate rainfall (70 mm), so conditions are generally comfortable for sightseeing and outdoor plans.

See Miramichi'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 →

Miramichi Weather in September — In Depth

☀️ September climate overview

September is one of the warmer months of the year in Miramichi, with average highs near 19.9°C and lows around 9.1°C (mean 14.5°C). It is about average for rainfall, averaging 70 mm of rainfall and 77% relative humidity across the period.

🌧️ Rain, humidity & wind in September

September averages 70 mm of rainfall in Miramichi, about average for rainfall compared with the rest of the year. The wettest September on record saw 173 mm (1999), and the driest just 23 mm (2025). Humidity sits around 77% and average wind speed is 0.3 m/s, with solar radiation averaging 3.7 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 3.1°C. Daytime highs moved from 18.5°C to 22.2°C and overnight lows from 8.3°C to 10.8°C over the same span.
September Weather in Miramichi, Year by Year
🔥 warmest❄️ coldest🌧️ wettest
YearAvg HighAvg TempAvg LowHottest DayColdest DayRainfallHumidityWindSolar
202523.2°C16.5°C9.8°C29.2°C4.2°C23 mm67%0.3 m/s4.3
202422.6°C17.0°C11.4°C31.5°C7.6°C41 mm74%0.3 m/s3.9
202323.1°C17.3°C11.5°C30.8°C4.3°C63 mm80%0.3 m/s3.4
202221.5°C15.8°C10.1°C29.8°C3.6°C39 mm71%0.4 m/s3.9
202120.8°C16.0°C11.1°C27.3°C6.5°C95 mm78%0.4 m/s3.4
202021.1°C15.0°C8.9°C28.4°C1.1°C26 mm69%0.4 m/s4
201919.1°C13.5°C8.0°C27.4°C2.2°C85 mm76%0.4 m/s3.6
201821.1°C15.1°C9.1°C30.0°C0.7°C59 mm72%0.4 m/s4
201723.1°C17.1°C11.1°C30.6°C3.3°C42 mm74%0.3 m/s3.5
201620.9°C15.4°C10.0°C28.2°C2.7°C59 mm77%0.3 m/s3.8
201523.3°C17.2°C11.2°C31.1°C3.3°C90 mm73%0.3 m/s4
201420.2°C14.6°C9.0°C29.0°C2.4°C44 mm73%0.4 m/s4
201318.9°C14.0°C9.0°C25.1°C3.2°C95 mm82%0.3 m/s3.2
201220.0°C14.8°C9.6°C27.2°C3.3°C77 mm78%0.3 m/s3.6
201120.2°C15.0°C9.8°C25.6°C3.8°C37 mm82%0.3 m/s4
201019.2°C14.6°C10.0°C33.0°C2.6°C98 mm81%0.3 m/s3.1
200919.9°C14.0°C8.0°C26.0°C-0.3°C52 mm75%0.3 m/s4.3
200818.7°C13.7°C8.7°C25.7°C0.9°C99 mm82%0.4 m/s3.6
200719.9°C14.3°C8.7°C29.7°C2.7°C65 mm74%0.4 m/s4
200619.3°C13.9°C8.5°C25.0°C4.3°C68 mm81%0.3 m/s3.7
200520.4°C15.3°C10.2°C27.1°C3.4°C107 mm78%0.3 m/s3.8
200419.8°C14.0°C8.3°C24.9°C3.5°C54 mm74%0.3 m/s4
200322.6°C16.7°C10.8°C30.3°C4.3°C30 mm76%0.3 m/s4.1
200220.8°C15.2°C9.6°C31.2°C0.2°C96 mm77%0.3 m/s3.4
200121.5°C15.8°C10.1°C31.4°C3.0°C64 mm73%0.3 m/s4.1
200019.0°C13.4°C7.8°C26.8°C0.5°C68 mm74%0.3 m/s3.9
1999 🔥 🌧️23.0°C17.7°C12.3°C31.0°C5.7°C173 mm79%0.3 m/s3.5
199818.5°C13.9°C9.2°C23.5°C3.9°C92 mm80%0.3 m/s3.5
199719.2°C14.0°C8.7°C26.1°C1.8°C43 mm78%0.3 m/s3.2
199618.8°C13.9°C9.0°C29.7°C3.3°C78 mm77%0.4 m/s3.5
199519.2°C12.8°C6.4°C25.1°C-0.1°C55 mm70%0.4 m/s4.2
199418.8°C13.5°C8.1°C24.8°C3.6°C58 mm76%0.3 m/s3.8
199319.6°C14.1°C8.6°C28.5°C2.4°C66 mm74%0.4 m/s3.8
199221.0°C15.0°C9.0°C26.7°C1.1°C27 mm74%0.3 m/s3.7
199117.4°C12.3°C7.2°C25.9°C-0.2°C96 mm79%0.3 m/s3.5
199018.2°C12.9°C7.6°C24.9°C1.9°C59 mm80%0.4 m/s3.5
198918.6°C13.5°C8.3°C28.5°C-1.1°C73 mm81%0.3 m/s3.8
198817.4°C12.3°C7.3°C23.9°C2.8°C58 mm79%0.4 m/s3.6
198717.4°C13.1°C8.8°C27.5°C-0.4°C133 mm82%0.4 m/s3.4
1986 ❄️15.9°C10.6°C5.3°C22.6°C0.7°C91 mm80%0.3 m/s3.7
198520.4°C14.6°C8.8°C28.1°C4.2°C47 mm74%0.3 m/s3.8
198417.4°C12.1°C6.8°C24.6°C1.5°C44 mm78%0.4 m/s4.1
198320.1°C14.7°C9.4°C29.9°C3.7°C73 mm80%0.3 m/s—
198217.5°C13.0°C8.5°C25.5°C1.7°C101 mm86%0.3 m/s—
198117.0°C12.6°C8.2°C23.3°C2.5°C105 mm84%0.4 m/s—

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

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Miramichi September Weather — FAQ

What is the average temperature in Miramichi in September?▼

The average high in September is around 19.9°C with lows near 9.1°C (mean 14.5°C), based on 45 years of NASA POWER data.

Does it rain a lot in Miramichi in September?▼

September averages 70 mm of rainfall in Miramichi, about average for rainfall. The wettest on record was 173 mm in 1999.

What was the hottest September on record in Miramichi?▼

The hottest September reached 33°C in 2010. The coldest dipped to -1.1°C in 1989.

Has September in Miramichi 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 3.1°C. Daytime highs moved from 18.5°C to 22.2°C and overnight lows from 8.3°C to 10.8°C over the same span.

Is September a good time to visit Miramichi?▼

September is one of the warmer months of the year in Miramichi and about average for rainfall, so plan for around 19.9°C daytime highs and 9.1°C at night.

Is September the coldest month in Miramichi?▼

Not quite — September is the 9th coolest month in Miramichi, averaging 14.5°C.

What should I pack for Miramichi in September?▼

For September in Miramichi, pack light layers you can adjust through the day, with typical highs of 19.9°C and lows of 9.1°C. Bring an umbrella or light rain jacket too.

Is Miramichi humid in September?▼

Relative humidity in September averages 77% — quite humid.

How windy is Miramichi in September?▼

Average wind speed in September is 0.3 m/s. The windiest September on record averaged 0.4 m/s (1981).

Which September had the most rainfall in Miramichi?▼

The wettest September on record was 1999 with 173 mm. On average, September sees 70 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.

Other New Brunswick cities

Explore how the weather in Miramichi 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.