Johnstown Weather in January (1981–2025)

📍 40.34°N, 78.90°W •
📊

January at a Glance in Johnstown

(1981–2025)
Avg High
🔥
-0.4°C
Avg Low
❄️
-8.0°C
Avg Temp
🌡️
-4.2°C
Avg Rain
🌧️
69 mm
Avg Humidity
💧
89%
Avg Wind
🌬️
0.8 m/s
Avg Solar
☀️
1.7
kWh/m²/day
vs Annual
📈
-13.3°C
temp difference
❄️Freezing afternoons🥶Freezing mornings☁️Cloudier skies🌧️Wet month🍃Light winds💦Humid air

Johnstown January Weather Overview

January is one of the cooler months of the year in Johnstown, with average highs near -0.4°C and lows around -8°C (mean -4.2°C). It is one of the drier months, averaging 69 mm of rainfall and 89% relative humidity across the period.

Johnstown January Temperature History (1981–2025)

Range

January is one of the cooler months of the year in Johnstown. Across 45 years of records, the warmest January in Johnstown was 2023 — when the month averaged 0.7°C — while the coldest was 1994 at -9.4°C. Typical January days reach -0.4°C with nights near -8°C. The long-term trend is warming, about 0.5°C per decade.

1981–1985 vs 2021–2025

Avg Temp-6.9°C→-3.4°C+3.5°C
Max Temp-3.1°C→0.1°C+3.2°C
Min Temp-10.7°C→-6.9°C+3.8°C

Trend (per decade)

Avg Temp+0.5°C/decade ↗
Max Temp+0.5°C/decade ↗
Min Temp+0.5°C/decade ↗

Distribution of Avg Temp

-10.0°C–-7.2°C6 yr (13%)
-7.2°C–-4.5°C16 yr (36%)
-4.5°C–-1.7°C15 yr (33%)
-1.7°C–1.0°C8 yr (18%)

Johnstown January Rainfall History (1981–2025)

Range

January is one of the drier months in Johnstown, averaging 69 mm of rainfall. The wettest January on record was 1996 with 145 mm, while the driest was 1981 at 21 mm.

Johnstown January Humidity History (1981–2025)

Range

Relative humidity in Johnstown during January averages 89%. The most humid January was 1994 at 98%, and the least humid was 2000 at 84%.

Johnstown January Solar History (1981–2025)

Range

January receives about 1.7 kWh/m²/day of solar energy in Johnstown. The sunniest Januarys were 1994, 2018 and 2022, among others at 1.9 kWh/m²/day, and the cloudiest was 2023 at 1.3.

Johnstown January Wind History (1981–2025)

Range

Average wind speed in Johnstown during January is 0.8 m/s. The windiest January was 1997 at 1 m/s, while the calmest was 1998 at 0.6 m/s.

What January Feels Like in Johnstown

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

How January Ranks in Johnstown

🥶1st coolest month of the year
🌵2nd driest month of the year
☀️11th sunniest month of the year

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

Explore Johnstown Weather by Month

Johnstown January Averages by Decade

Metric1980s1990s2000s2010s2020sChange
Avg Temp-5.9°C-3.7°C-3.7°C-4.4°C-2.9°C+3°C
Avg High-2.0°C0.2°C0.1°C-0.6°C0.7°C+2.7°C
Avg Low-9.8°C-7.5°C-7.5°C-8.2°C-6.5°C+3.3°C
Avg Rain53 mm83 mm70 mm64 mm73 mm+20 mm

Extreme January Records in Johnstown

🔥Warmest January17.6°C2018
🧊Coldest January-29.5°C1994
🌧️Wettest January145 mm1996
🏜️Driest January21 mm1981
🌬️Windiest January1 m/s1997

Key Insights for January

✅

January temperatures in Johnstown have risen by about 3.5°C between 1981–1985 and 2021–2025.

✅

January has ranged from a record low of -29.5°C (1994) to a record high of 17.6°C (2018).

✅

Rainfall in January is one of the drier months, averaging 69 mm, with a wettest year of 145 mm.

Is January a Good Time to Visit Johnstown?

A quieter season to visit Johnstown

If your dates are flexible, the more temperate months of July and August tend to be the most comfortable for visiting Johnstown. That said, January — with days averaging -0.4°C and nights around -8°C (mean -4.2°C) and moderate rainfall (69 mm) — can still be rewarding for travellers who don't mind the cooler conditions, and often means fewer crowds.

See Johnstown'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 →

Johnstown Weather in January — In Depth

☀️ January climate overview

January is one of the cooler months of the year in Johnstown, with average highs near -0.4°C and lows around -8°C (mean -4.2°C). It is one of the drier months, averaging 69 mm of rainfall and 89% relative humidity across the period.

🌧️ Rain, humidity & wind in January

January averages 69 mm of rainfall in Johnstown, one of the drier months compared with the rest of the year. The wettest January on record saw 145 mm (1996), and the driest just 21 mm (1981). Humidity sits around 89% and average wind speed is 0.8 m/s, with solar radiation averaging 1.7 kWh/m²/day.

📈 How January has changed

Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average January temperatures have risen by about 3.5°C. Daytime highs moved from -3.1°C to 0.1°C and overnight lows from -10.7°C to -6.9°C over the same span.
January Weather in Johnstown, Year by Year
🔥 warmest❄️ coldest🌧️ wettest
YearAvg HighAvg TempAvg LowHottest DayColdest DayRainfallHumidityWindSolar
2025-3.1°C-6.6°C-10.2°C7.5°C-22.7°C40 mm89%0.8 m/s1.8
20240.9°C-2.5°C-5.9°C13.4°C-15.1°C142 mm91%0.7 m/s1.4
2023 🔥3.8°C0.7°C-2.3°C16.2°C-8.2°C94 mm91%0.7 m/s1.3
2022-1.6°C-5.8°C-10.1°C11.9°C-18.0°C58 mm86%0.7 m/s1.9
20210.6°C-2.6°C-5.8°C6.1°C-11.6°C36 mm88%0.7 m/s1.6
20203.8°C-0.4°C-4.7°C15.6°C-12.7°C70 mm87%0.7 m/s1.5
2019-0.9°C-4.8°C-8.7°C12.6°C-23.1°C75 mm91%0.8 m/s1.5
2018-0.6°C-5.0°C-9.3°C17.6°C-19.3°C62 mm87%0.8 m/s1.9
20172.4°C-0.9°C-4.3°C16.1°C-15.8°C98 mm88%0.8 m/s1.5
2016-0.5°C-4.7°C-8.8°C12.9°C-16.3°C51 mm85%0.8 m/s1.7
2015-1.7°C-5.8°C-9.8°C11.2°C-17.7°C55 mm86%0.8 m/s1.7
2014-2.5°C-7.0°C-11.5°C7.5°C-23.0°C32 mm85%0.8 m/s1.7
20130.8°C-3.0°C-6.7°C16.2°C-17.6°C76 mm91%0.7 m/s1.6
20121.9°C-1.8°C-5.6°C10.0°C-14.4°C84 mm89%0.8 m/s1.7
2011-2.4°C-5.9°C-9.4°C7.4°C-18.7°C34 mm89%0.7 m/s1.5
2010-2.3°C-5.4°C-8.4°C7.7°C-17.0°C72 mm92%0.8 m/s1.6
2009-3.4°C-7.2°C-11.0°C4.6°C-24.1°C60 mm92%0.7 m/s1.7
20081.2°C-2.7°C-6.6°C16.6°C-15.9°C55 mm87%0.8 m/s1.8
20072.7°C-1.1°C-4.8°C13.9°C-13.3°C79 mm87%0.8 m/s1.5
20064.6°C0.5°C-3.7°C12.3°C-11.3°C100 mm89%0.8 m/s1.7
20050.5°C-3.5°C-7.6°C14.0°C-18.7°C134 mm92%0.7 m/s1.7
2004-4.2°C-7.7°C-11.3°C15.4°C-18.8°C96 mm91%0.9 m/s1.7
2003-4.2°C-7.3°C-10.4°C5.2°C-16.2°C53 mm88%0.8 m/s1.5
20023.8°C-0.2°C-4.2°C16.1°C-12.5°C48 mm86%0.7 m/s1.8
20010.3°C-3.5°C-7.4°C6.7°C-12.9°C40 mm90%0.7 m/s1.6
2000-0.1°C-4.0°C-7.8°C13.3°C-15.6°C36 mm84%0.8 m/s1.8
19990.3°C-3.9°C-8.2°C15.3°C-20.2°C113 mm92%0.8 m/s1.8
19983.5°C0.0°C-3.4°C16.1°C-14.4°C85 mm91%0.6 m/s1.6
1997-0.8°C-4.6°C-8.4°C16.3°C-18.3°C54 mm88%1 m/s1.6
1996 🌧️-2.5°C-6.5°C-10.5°C11.0°C-20.5°C145 mm94%0.8 m/s1.6
19951.0°C-2.5°C-6.1°C15.0°C-14.6°C68 mm90%0.8 m/s1.8
1994 ❄️-5.5°C-9.4°C-13.2°C3.0°C-29.5°C95 mm98%0.8 m/s1.9
19931.5°C-2.2°C-5.9°C11.2°C-11.6°C57 mm87%0.8 m/s1.4
19920.8°C-3.1°C-6.9°C10.0°C-15.3°C56 mm89%0.8 m/s1.6
1991-0.1°C-4.2°C-8.2°C5.6°C-15.9°C74 mm90%0.8 m/s1.7
19903.3°C-0.4°C-4.0°C14.3°C-11.3°C78 mm89%0.8 m/s1.6
19892.5°C-1.9°C-6.2°C8.8°C-15.8°C61 mm87%0.8 m/s1.7
1988-1.9°C-6.0°C-10.2°C11.5°C-19.7°C46 mm87%0.7 m/s1.6
1987-2.2°C-5.9°C-9.5°C5.9°C-25.7°C74 mm95%0.8 m/s1.7
1986-0.7°C-4.6°C-8.4°C11.4°C-16.8°C58 mm89%0.8 m/s1.7
1985-4.1°C-7.5°C-10.8°C15.0°C-26.9°C45 mm91%0.9 m/s1.9
1984-3.5°C-8.0°C-12.4°C4.0°C-26.8°C35 mm95%0.7 m/s1.6
19830.2°C-3.3°C-6.9°C4.9°C-17.1°C37 mm87%0.7 m/s—
1982-4.6°C-8.7°C-12.8°C6.3°C-26.3°C100 mm90%0.9 m/s—
1981-3.5°C-7.0°C-10.6°C7.1°C-18.8°C21 mm89%0.8 m/s—

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

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Johnstown January Weather — FAQ

What is the average temperature in Johnstown in January?▼

The average high in January is around -0.4°C with lows near -8°C (mean -4.2°C), based on 45 years of NASA POWER data.

Does it rain a lot in Johnstown in January?▼

January averages 69 mm of rainfall in Johnstown, one of the drier months. The wettest on record was 145 mm in 1996.

What was the hottest January on record in Johnstown?▼

The hottest January reached 17.6°C in 2018. The coldest dipped to -29.5°C in 1994.

Has January in Johnstown gotten warmer over time?▼

Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average January temperatures have risen by about 3.5°C. Daytime highs moved from -3.1°C to 0.1°C and overnight lows from -10.7°C to -6.9°C over the same span.

Is January a good time to visit Johnstown?▼

January is one of the cooler months of the year in Johnstown and one of the drier months, so plan for around -0.4°C daytime highs and -8°C at night.

Is January the coldest month in Johnstown?▼

Yes — January is the coldest month of the year in Johnstown, averaging -4.2°C.

What should I pack for Johnstown in January?▼

For January in Johnstown, pack warm layers and a jacket for chilly mornings, with typical highs of -0.4°C and lows of -8°C. Bring an umbrella or light rain jacket too.

Is Johnstown humid in January?▼

Relative humidity in January averages 89% — quite humid.

How windy is Johnstown in January?▼

Average wind speed in January is 0.8 m/s. The windiest January on record averaged 1 m/s (1997).

Which January had the most rainfall in Johnstown?▼

The wettest January on record was 1996 with 145 mm. On average, January sees 69 mm.

Where does this January 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 Johnstown behaves each January, 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 January specifically, along with year-by-year records and how the month has changed over the decades.