Onalaska, United States experiences average highs of 14°C (57°F) and lows of 5°C (41°F) throughout the year. Rainfall is moderate, averaging about 9 rainy days per month. Average highs have stayed broadly stable across the available records.
Onalaska, United States Weather & Climate 2026
Monthly climate averages for Onalaska, United States. Based on 10-year ERA5 reanalysis data.
Climate Overview
Drier season: Jan–Dec 
Wetter season: Apr–Oct At-a-Glance Climate Summary
Live Weather & Air Quality
Key figures
Climate Score
5.2/10
Best: May, June, July, August, September
UV Index
4
Low
Temperature 14°C / 5°C
Feels Like 12°C / 3°C
Rainy Days 9
Rainfall 82 mm
Sunshine 8 h
Humidity 70%
Wind Speed 18 km/h
Dew Point 4°C
Snow Days 6 days
Frost Days 18 days
Hottest Month
28°C
July
Avg Low19°C
Rain10days
Coldest Month
-11°C
January
Avg High-2°C
Rain6days
Driest Month
6days
January
Avg High-2°C
Avg Low-11°C
Windiest Month
21 km/h
April (Gusts 46)
Worst Time to Visit
Consider avoiding January, March, November, December due to very cold temperatures.
Sun Position
Sunrise 05:23
Daylight 15.5h
Sunset 20:50
Live conditions—
Onalaska on the map · live conditions
Onalaska, United States
- Continent
- Americas
- Country
- United States
- City
- Onalaska
- Population
- 18.5K
- Elevation
- 216 m
- Coordinates
- 43.88°, -91.24°
Seasonal Breakdown
Spring
Mar–May
Avg High 14°C
Avg Low 4°C
Rain 11 days/mo
1/3 best months
Summer
Jun–Aug
Avg High 27°C
Avg Low 18°C
Rain 11 days/mo
3/3 best months
Autumn
Sep–Nov
Avg High 16°C
Avg Low 8°C
Rain 8 days/mo
1/3 best months
Winter
Dec–Feb
Avg High -1°C
Avg Low -9°C
Rain 7 days/mo
Climate Charts
Based on historical averages (2016–2025)
Monthly Temperatures
HighLowShaded bands show the typical range across the available yearly records.
Line chart showing monthly temperatures. Jan: -2°C / -11°C . Feb: 0°C / -10°C . Mar: 8°C / -2°C . Apr: 14°C / 3°C . May: 21°C / 11°C . Jun: 27°C / 17°C . Jul: 28°C / 19°C . Aug: 27°C / 18°C . Sep: 24°C / 15°C . Oct: 16°C / 8°C . Nov: 7°C / 0°C . Dec: 0°C / -7°C .
Monthly Rainfall
Rainfall
Bar chart showing monthly rainfall. Jan: 34 mm. Feb: 36 mm. Mar: 72 mm. Apr: 88 mm. May: 116 mm. Jun: 130 mm. Jul: 107 mm. Aug: 113 mm. Sep: 97 mm. Oct: 88 mm. Nov: 54 mm. Dec: 44 mm.
Monthly Humidity
Humidity
Line chart showing monthly humidity. Jan: 75%. Feb: 70%. Mar: 65%. Apr: 65%. May: 67%. Jun: 68%. Jul: 72%. Aug: 73%. Sep: 72%. Oct: 69%. Nov: 70%. Dec: 74%.
Monthly Wind Speed
Wind SpeedGusts
Bar chart showing monthly wind speed. Jan: 17 km/h . Feb: 19 km/h . Mar: 19 km/h . Apr: 21 km/h . May: 18 km/h . Jun: 17 km/h . Jul: 15 km/h . Aug: 15 km/h . Sep: 16 km/h . Oct: 19 km/h . Nov: 19 km/h . Dec: 18 km/h .
Sunshine
Sunshine
Sunshine: Jan: 5h. Feb: 7h. Mar: 8h. Apr: 8h. May: 10h. Jun: 12h. Jul: 12h. Aug: 11h. Sep: 9h. Oct: 7h. Nov: 6h. Dec: 5h.
UV Index
UV Index
Bar chart showing monthly UV index. Jan: UV 2. Feb: UV 3. Mar: UV 4. Apr: UV 5. May: UV 6. Jun: UV 7. Jul: UV 7. Aug: UV 6. Sep: UV 5. Oct: UV 4. Nov: UV 2. Dec: UV 2.
Monthly Daylight Hours
Daylight12h reference
Monthly Dew Point & Comfort
Dew Point Dry Comfortable Humid Muggy Oppressive
Snow Days
Snow DaysSnowfall
Snow Days: Jan: 10 days. Feb: 9 days. Mar: 6 days. Apr: 4 days. May: 0 days. Jun: 0 days. Jul: 0 days. Aug: 0 days. Sep: 0 days. Oct: 1 days. Nov: 5 days. Dec: 10 days.
Climate Trends
Average highs have stayed broadly stable across the available records. Average rainfall is trending drier by about 9 mm.
2016 to 2025
Avg high Avg rainfall
Climate summary
| Last 12 months | All years | |
|---|---|---|
| Hottest month | Jul 2025 · 29°C | Jul · 28°C |
| Coldest month | Dec 2025 · -11°C | Jan · -11°C |
| Wettest month | Jul 2025 · 129 mm | Jun · 130 mm |
| Windiest month | Mar 2025 · 21 km/h | Apr · 21 km/h |
Month-by-Month Weather Table
January
Poor 
February
Poor March
Poor April
Fair May best
Good June best
Excellent July best
Excellent August best
Excellent September best
Excellent October
Fair November
Poor December
Poor | Month | Temp | Feels Like | Rain | Sun | Humidity | UV | Status | Details |
|---|---|---|---|---|---|---|---|---|
| January | -2°C / -11°C | -7°C / -16°C | 6days (34 mm) Good | 5.3h Fair | 75% Muggy | 2 Low | Poor | View Details |
| February | 0°C / -10°C | -4°C / -15°C | 6days (36 mm) Good | 7.2h Good | 70% Muggy | 3.2 Moderate | Poor | View Details |
| March | 8°C / -2°C | 4°C / -6°C | 9days (72 mm) Wet | 7.9h Good | 65% Muggy | 4.1 Moderate | Poor | View Details |
| April | 14°C / 3°C | 11°C / -1°C | 12days (88 mm) Wet | 8.4h Good | 65% Muggy | 4.8 Moderate | Fair | View Details |
| May best | 21°C / 11°C | 20°C / 9°C | 12days (116 mm) Wet | 10.2h Excellent | 67% Muggy | 6.2 High | Good | View Details |
| June best | 27°C / 17°C | 28°C / 17°C | 13days (130 mm) Wet | 11.6h Excellent | 68% Muggy | 6.6 High | Excellent | View Details |
| July best | 28°C / 19°C | 31°C / 20°C | 10days (107 mm) Wet | 12.2h Excellent | 72% Muggy | 6.8 High | Excellent | View Details |
| August best | 27°C / 18°C | 29°C / 19°C | 11days (113 mm) Wet | 10.9h Excellent | 73% Muggy | 6.2 High | Excellent | View Details |
| September best | 24°C / 15°C | 24°C / 14°C | 9days (97 mm) Wet | 9.3h Good | 72% Muggy | 5.1 High | Excellent | View Details |
| October | 16°C / 8°C | 13°C / 5°C | 10days (88 mm) Wet | 7h Good | 69% Muggy | 3.6 Moderate | Fair | View Details |
| November | 7°C / 0°C | 3°C / -4°C | 6days (54 mm) Good | 5.8h Fair | 70% Muggy | 2.2 Moderate | Poor | View Details |
| December | 0°C / -7°C | -4°C / -12°C | 8days (44 mm) Wet | 4.9h Fair | 74% Muggy | 1.8 Low | Poor | View Details |
Compare Nearby City Climates
Frequently Asked Questions
The best months to visit Onalaska are May, June, July, August, September, when temperatures are comfortable and rainfall is at its lowest. This is based on 10-year climate averages for Onalaska, scoring temperature, rainfall, humidity, and sunshine hours.
The hottest month in Onalaska is July, with average daytime highs of 28°C (83°F). Plan outdoor activities for early morning or late afternoon if visiting during this period.
The coldest month in Onalaska is January, with average overnight lows of -11°C (12°F). Pack warm layers and expect shorter daylight hours during this period.
The wettest month in Onalaska is June, averaging 130mm of precipitation across 13 rainy days. An umbrella or waterproof jacket is essential.
The rainy season in Onalaska runs through June, April, May, August, with the heaviest rainfall in June. Based on 10-year averages for Onalaska.
Onalaska receives approximately 101 sunshine hours per year. The sunniest month is July with around 12 hours. Based on climate data for Onalaska.
The least favorable months to visit Onalaska are January, March, November, December, primarily due to very cold temperatures. For the best conditions, consider May, June, July, August, September instead.
The annual average UV index in Onalaska is 4, classified as moderate. Standard sun protection (sunscreen, hat) is recommended during prolonged outdoor exposure.
Average humidity in Onalaska is 70%, classified as moderate. Humidity levels are generally comfortable and should not affect outdoor activities for most people.
Yes, Onalaska receives snow. Months with snowfall average 6 snow days and 13 cm (5 in) of accumulation, with about 18 frost days during winter.
Average wind speeds in Onalaska are 18 km/h (11 mph). The windiest month is April with peak winds reaching 21 km/h (13 mph) (gusts up to 46 km/h / 29 mph).
Onalaska averages 4 clear-sky days per month with overall cloud cover around 60%. The clearest skies occur in September.
The annual average dew point in Onalaska is 4°C (39°F), which feels dry and comfortable. Outdoor activities are comfortable year-round from a humidity standpoint.
Onalaska has a Hot-Summer Continental climate, classified as Dfa under the Köppen system. Continental climates experience extreme temperature ranges — hot summers and cold, snowy winters.
The 'feels like' temperature in Onalaska ranges from 3°C (37°F) to 12°C (54°F) on average. The 'feels like' temperature closely matches the actual temperature throughout most of the year.
Yes, June is a great time to visit Onalaska. It earns a climate score of 8.4/10 with Excellent.
For June in Onalaska, pack Umbrella, Waterproof jacket, Breathable clothing, Sunscreen (SPF 30+), Sun hat. With average highs of 27°C (80°F) and 13 rainy days, these essentials will keep you comfortable.
Data Source
Climate data derived from ERA5 reanalysis (ECMWF), averaged over 2016–2025. Sea surface temperature from marine reanalysis data. Climate scores and seasonal estimates are computed by WorldStats.
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