Round Lake Weather in January (1981–2025)

📍 42.35°N, 88.11°W •
📊

January at a Glance in Round Lake

(1981–2025)
Avg High
🔥
-2.6°C
Avg Low
❄️
-11.2°C
Avg Temp
🌡️
-6.9°C
Avg Rain
🌧️
41 mm
Avg Humidity
💧
89%
Avg Wind
🌬️
4.3 m/s
Avg Solar
☀️
1.7
kWh/m²/day
vs Annual
📈
-15.6°C
temp difference
❄️Freezing afternoons🥶Freezing mornings☁️Cloudier skies🌦️Some rain💨Breezy💦Humid air

Round Lake January Weather Overview

January is one of the cooler months of the year in Round Lake, with average highs near -2.6°C and lows around -11.2°C (mean -6.9°C). It is one of the drier months, averaging 41 mm of rainfall and 89% relative humidity across the period.

Round Lake January Temperature History (1981–2025)

Range

January is one of the cooler months of the year in Round Lake. Across 45 years of records, the warmest January in Round Lake was 2006 — when the month averaged 0.1°C — while the coldest was 1982 at -14.1°C. Typical January days reach -2.6°C with nights near -11.2°C. The long-term trend is warming, about 0.7°C per decade.

1981–1985 vs 2021–2025

Avg Temp-10.0°C→-5.8°C+4.2°C
Max Temp-5.2°C→-1.8°C+3.4°C
Min Temp-14.8°C→-9.7°C+5.1°C

Trend (per decade)

Avg Temp+0.7°C/decade ↗
Max Temp+0.5°C/decade ↗
Min Temp+0.8°C/decade ↗

Distribution of Avg Temp

-15.0°C–-11.0°C6 yr (13%)
-11.0°C–-7.0°C14 yr (31%)
-7.0°C–-3.0°C21 yr (47%)
-3.0°C–1.0°C4 yr (9%)

Round Lake January Rainfall History (1981–2025)

Range

January is one of the drier months in Round Lake, averaging 41 mm of rainfall. The wettest January on record was 1999 with 90 mm, while the driest was 1981 at 3 mm.

Round Lake January Humidity History (1981–2025)

Range

Relative humidity in Round Lake during January averages 89%. The most humid January was 1988 at 97%, and the least humid was 2025 at 76%.

Round Lake January Solar History (1981–2025)

Range

January receives about 1.7 kWh/m²/day of solar energy in Round Lake. The sunniest January was 2022 at 2.3 kWh/m²/day, and the cloudiest were 2017 and 2023 at 1.3.

Round Lake January Wind History (1981–2025)

Range

Average wind speed in Round Lake during January is 4.3 m/s. The windiest January was 2014 at 5.1 m/s, while the calmest was 2023 at 3.5 m/s.

What January Feels Like in Round Lake

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

How January Ranks in Round Lake

🥶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 Round Lake Weather by Month

Round Lake January Averages by Decade

Metric1980s1990s2000s2010s2020sChange
Avg Temp-8.7°C-7.1°C-5.8°C-6.9°C-5.5°C+3.2°C
Avg High-4.1°C-2.7°C-1.7°C-2.6°C-1.5°C+2.6°C
Avg Low-13.4°C-11.5°C-9.8°C-11.3°C-9.4°C+4°C
Avg Rain27 mm53 mm41 mm40 mm44 mm+17 mm

Extreme January Records in Round Lake

🔥Warmest January14.7°C2008
🧊Coldest January-38.3°C1982
🌧️Wettest January90 mm1999
🏜️Driest January3 mm1981
🌬️Windiest January5.1 m/s2014

Key Insights for January

✅

January temperatures in Round Lake have risen by about 4.2°C between 1981–1985 and 2021–2025.

✅

January has ranged from a record low of -38.3°C (1982) to a record high of 14.7°C (2008).

✅

Rainfall in January is one of the drier months, averaging 41 mm, with a wettest year of 90 mm.

✅

Daytime highs and overnight lows have shifted differently — highs rose about 0.5°C per decade while lows rose 0.8°C per decade, narrowing the gap between day and night.

Is January a Good Time to Visit Round Lake?

A quieter season to visit Round Lake

If your dates are flexible, the more temperate months of August and July tend to be the most comfortable for visiting Round Lake. That said, January — with days averaging -2.6°C and nights around -11.2°C (mean -6.9°C) and moderate rainfall (41 mm) — can still be rewarding for travellers who don't mind the cooler conditions, and often means fewer crowds.

See Round Lake'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 →

Round Lake Weather in January — In Depth

☀️ January climate overview

January is one of the cooler months of the year in Round Lake, with average highs near -2.6°C and lows around -11.2°C (mean -6.9°C). It is one of the drier months, averaging 41 mm of rainfall and 89% relative humidity across the period.

🌧️ Rain, humidity & wind in January

January averages 41 mm of rainfall in Round Lake, one of the drier months compared with the rest of the year. The wettest January on record saw 90 mm (1999), and the driest just 3 mm (1981). Humidity sits around 89% and average wind speed is 4.3 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 4.2°C. Daytime highs moved from -5.2°C to -1.8°C and overnight lows from -14.8°C to -9.7°C over the same span.
January Weather in Round Lake, Year by Year
🔥 warmest❄️ coldest🌧️ wettest
YearAvg HighAvg TempAvg LowHottest DayColdest DayRainfallHumidityWindSolar
2025-2.6°C-7.0°C-11.4°C9.5°C-22.8°C14 mm76%4.9 m/s2.1
2024-2.5°C-5.7°C-8.8°C5.4°C-27.2°C69 mm93%3.8 m/s1.7
20231.1°C-2.3°C-5.8°C8.1°C-25.0°C52 mm89%3.5 m/s1.3
2022-4.0°C-8.7°C-13.4°C3.6°C-24.5°C15 mm85%4.6 m/s2.3
2021-1.2°C-5.3°C-9.3°C2.5°C-19.5°C52 mm91%3.6 m/s1.6
20200.1°C-3.8°C-7.6°C6.5°C-17.3°C62 mm91%4 m/s1.4
2019-4.3°C-8.8°C-13.3°C8.1°C-37.1°C56 mm90%4.2 m/s1.6
2018-1.7°C-5.7°C-9.8°C10.1°C-23.3°C47 mm85%4.7 m/s1.8
2017-0.1°C-3.8°C-7.5°C10.6°C-20.4°C56 mm86%3.9 m/s1.3
2016-2.4°C-6.6°C-10.8°C6.6°C-23.0°C19 mm90%3.9 m/s1.8
2015-2.5°C-6.8°C-11.2°C5.1°C-24.4°C26 mm87%3.9 m/s1.6
2014-7.0°C-12.8°C-18.5°C1.5°C-30.9°C39 mm93%5.1 m/s1.9
2013-1.1°C-5.7°C-10.4°C14.0°C-21.4°C79 mm84%4.7 m/s1.9
20120.9°C-3.4°C-7.8°C8.9°C-19.6°C33 mm87%4.4 m/s1.8
2011-3.8°C-7.5°C-11.2°C0.6°C-25.5°C24 mm86%3.8 m/s1.6
2010-3.9°C-8.0°C-12.1°C4.7°C-23.5°C22 mm93%4 m/s2
2009-6.0°C-11.2°C-16.4°C1.3°C-31.7°C30 mm92%4.1 m/s2.1
2008-1.5°C-6.2°C-11.0°C14.7°C-24.3°C49 mm89%4.9 m/s1.6
2007-0.1°C-3.9°C-7.8°C9.0°C-18.6°C40 mm87%4.6 m/s1.6
2006 🔥3.4°C0.1°C-3.1°C9.5°C-10.2°C74 mm87%4.3 m/s1.6
2005-2.9°C-6.8°C-10.6°C6.9°C-22.8°C90 mm89%3.9 m/s1.4
2004-4.2°C-8.1°C-12.1°C10.1°C-24.3°C20 mm85%4.6 m/s1.5
2003-3.7°C-7.5°C-11.4°C8.9°C-20.9°C10 mm77%4.6 m/s2
20022.0°C-1.6°C-5.2°C11.0°C-14.0°C27 mm87%4.3 m/s1.8
2001-2.7°C-6.9°C-11.1°C1.5°C-18.6°C34 mm96%3.7 m/s1.9
2000-1.7°C-5.5°C-9.4°C10.9°C-20.5°C34 mm85%4.4 m/s1.8
1999 🌧️-4.0°C-8.3°C-12.7°C4.5°C-28.1°C90 mm94%4.3 m/s1.8
19980.2°C-3.6°C-7.5°C9.5°C-22.0°C63 mm91%3.8 m/s1.9
1997-4.0°C-8.3°C-12.6°C13.7°C-27.4°C47 mm89%4.7 m/s1.8
1996-2.7°C-7.5°C-12.2°C12.5°C-32.2°C44 mm88%4.8 m/s1.6
1995-2.9°C-6.8°C-10.6°C4.3°C-19.0°C59 mm91%4.1 m/s1.6
1994-7.0°C-11.3°C-15.6°C1.8°C-32.7°C43 mm92%4.3 m/s1.7
1993-2.6°C-7.5°C-12.3°C3.5°C-22.0°C65 mm92%4 m/s1.7
1992-0.6°C-4.3°C-8.0°C3.5°C-24.2°C38 mm90%4.3 m/s1.5
1991-5.5°C-10.9°C-16.4°C0.9°C-27.2°C29 mm96%4.4 m/s1.8
19902.2°C-2.6°C-7.3°C9.1°C-15.4°C52 mm85%4.8 m/s1.8
19891.3°C-3.3°C-8.0°C13.0°C-22.2°C16 mm87%4.9 m/s1.6
1988-6.7°C-11.7°C-16.8°C7.7°C-32.4°C63 mm97%4.6 m/s1.5
1987-1.5°C-5.2°C-8.8°C4.3°C-22.8°C26 mm88%3.9 m/s1.9
1986-3.8°C-8.3°C-12.8°C6.5°C-28.1°C21 mm93%4.6 m/s1.7
1985-7.2°C-12.6°C-18.0°C-0.1°C-35.5°C30 mm94%4.8 m/s2.1
1984-6.1°C-10.8°C-15.6°C0.3°C-34.3°C20 mm95%3.9 m/s1.8
1983-0.6°C-4.3°C-8.1°C3.4°C-15.3°C13 mm87%4.2 m/s—
1982 ❄️-8.4°C-14.1°C-19.7°C0.8°C-38.3°C52 mm95%5 m/s—
1981-3.7°C-8.1°C-12.4°C7.0°C-25.5°C3 mm88%4 m/s—

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

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Round Lake January Weather — FAQ

What is the average temperature in Round Lake in January?▼

The average high in January is around -2.6°C with lows near -11.2°C (mean -6.9°C), based on 45 years of NASA POWER data.

Does it rain a lot in Round Lake in January?▼

January averages 41 mm of rainfall in Round Lake, one of the drier months. The wettest on record was 90 mm in 1999.

What was the hottest January on record in Round Lake?▼

The hottest January reached 14.7°C in 2008. The coldest dipped to -38.3°C in 1982.

Has January in Round Lake 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 4.2°C. Daytime highs moved from -5.2°C to -1.8°C and overnight lows from -14.8°C to -9.7°C over the same span.

Is January a good time to visit Round Lake?▼

January is one of the cooler months of the year in Round Lake and one of the drier months, so plan for around -2.6°C daytime highs and -11.2°C at night.

Is January the coldest month in Round Lake?▼

Yes — January is the coldest month of the year in Round Lake, averaging -6.9°C.

What should I pack for Round Lake in January?▼

For January in Round Lake, pack warm layers and a jacket for chilly mornings, with typical highs of -2.6°C and lows of -11.2°C.

Is Round Lake humid in January?▼

Relative humidity in January averages 89% — quite humid.

How windy is Round Lake in January?▼

Average wind speed in January is 4.3 m/s. The windiest January on record averaged 5.1 m/s (2014).

Which January had the most rainfall in Round Lake?▼

The wettest January on record was 1999 with 90 mm. On average, January sees 41 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 Round Lake 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.