River Forest, United States experiences average highs of 15°C (59°F) and lows of 7°C (45°F) throughout the year. Rainfall is moderate, averaging about 10 rainy days per month. Sunshine is abundant, averaging about 9 hours per day. Average highs have stayed broadly stable across the available records.
River Forest, United States Weather & Climate 2026
Monthly climate averages for River Forest, United States. Based on 10-year ERA5 reanalysis data.
Climate Overview
Drier season: Jan–Dec 
Wetter season: Mar–Oct At-a-Glance Climate Summary
Live Weather & Air Quality
Key figures
Climate Score
5.2/10
Best: June, July, August, September
UV Index
5
Low
Temperature 15°C / 7°C
Feels Like 13°C / 4°C
Rainy Days 10
Rainfall 83 mm
Sunshine 9 h
Humidity 71%
Wind Speed 22 km/h
Dew Point 6°C
Snow Days 6 days
Frost Days 16 days
Hottest Month
28°C
July
Avg Low20°C
Rain11days
Coldest Month
-6°C
January
Avg High0°C
Rain9days
Driest Month
8days
February
Avg High3°C
Avg Low-5°C
Windiest Month
25 km/h
February (Gusts 44)
Worst Time to Visit
Consider avoiding January, February, March, December due to very cold temperatures.
Sun Position
Sunrise 05:17
Daylight 15.2h
Sunset 20:29
Live conditions—
River Forest on the map · live conditions
River Forest, United States
- Continent
- Americas
- Country
- United States
- City
- River Forest
- Population
- 11.2K
- Elevation
- 192 m
- Coordinates
- 41.90°, -87.81°
Seasonal Breakdown
Spring
Mar–May
Avg High 14°C
Avg Low 5°C
Rain 12 days/mo
Summer
Jun–Aug
Avg High 27°C
Avg Low 19°C
Rain 11 days/mo
3/3 best months
Autumn
Sep–Nov
Avg High 17°C
Avg Low 10°C
Rain 9 days/mo
1/3 best months
Winter
Dec–Feb
Avg High 2°C
Avg Low -4°C
Rain 8 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: 0°C / -6°C . Feb: 3°C / -5°C . Mar: 9°C / 1°C . Apr: 14°C / 5°C . May: 20°C / 11°C . Jun: 26°C / 17°C . Jul: 28°C / 20°C . Aug: 27°C / 19°C . Sep: 24°C / 17°C . Oct: 17°C / 10°C . Nov: 9°C / 3°C . Dec: 4°C / -3°C .
Monthly Rainfall
Rainfall
Bar chart showing monthly rainfall. Jan: 65 mm. Feb: 53 mm. Mar: 90 mm. Apr: 108 mm. May: 120 mm. Jun: 101 mm. Jul: 92 mm. Aug: 78 mm. Sep: 67 mm. Oct: 105 mm. Nov: 57 mm. Dec: 60 mm.
Monthly Humidity
Humidity
Line chart showing monthly humidity. Jan: 73%. Feb: 69%. Mar: 69%. Apr: 69%. May: 73%. Jun: 71%. Jul: 74%. Aug: 73%. Sep: 71%. Oct: 69%. Nov: 69%. Dec: 72%.
Monthly Wind Speed
Wind SpeedGusts
Bar chart showing monthly wind speed. Jan: 24 km/h . Feb: 25 km/h . Mar: 24 km/h . Apr: 24 km/h . May: 21 km/h . Jun: 20 km/h . Jul: 18 km/h . Aug: 17 km/h . Sep: 19 km/h . Oct: 24 km/h . Nov: 25 km/h . Dec: 24 km/h .
Sunshine
Sunshine
Sunshine: Jan: 5h. Feb: 7h. Mar: 8h. Apr: 9h. May: 10h. Jun: 12h. Jul: 12h. Aug: 12h. Sep: 10h. Oct: 8h. Nov: 6h. Dec: 5h.
UV Index
UV Index
Bar chart showing monthly UV index. Jan: UV 2. Feb: UV 3. Mar: UV 5. Apr: UV 6. May: UV 7. Jun: UV 7. Jul: UV 7. Aug: UV 7. Sep: UV 5. Oct: UV 4. Nov: UV 3. 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: 12 days. Feb: 9 days. Mar: 5 days. Apr: 3 days. May: 0 days. Jun: 0 days. Jul: 0 days. Aug: 0 days. Sep: 0 days. Oct: 1 days. Nov: 3 days. Dec: 7 days.
Climate Trends
Average highs have stayed broadly stable across the available records. Average rainfall has remained broadly steady.
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 | Jan 2025 · -7°C | Jan · -6°C |
| Wettest month | Jun 2025 · 124 mm | May · 120 mm |
| Windiest month | Jan 2025 · 27 km/h | Feb · 25 km/h |
Month-by-Month Weather Table
January
Poor 
February
Poor March
Poor April
Fair May
Good June best
Excellent July best
Excellent August best
Excellent September best
Excellent October
Good November
Poor December
Poor | Month | Temp | Feels Like | Rain | Sun | Humidity | UV | Status | Details |
|---|---|---|---|---|---|---|---|---|
| January | 0°C / -6°C | -4°C / -11°C | 9days (65 mm) Wet | 5.2h Fair | 73% Muggy | 2.1 Moderate | Poor | View Details |
| February | 3°C / -5°C | -1°C / -10°C | 8days (53 mm) Wet | 6.9h Fair | 69% Muggy | 3.4 Moderate | Poor | View Details |
| March | 9°C / 1°C | 5°C / -4°C | 11days (90 mm) Wet | 7.9h Good | 69% Muggy | 4.6 Moderate | Poor | View Details |
| April | 14°C / 5°C | 11°C / 0°C | 13days (108 mm) Wet | 9.1h Good | 69% Muggy | 5.5 High | Fair | View Details |
| May | 20°C / 11°C | 19°C / 8°C | 13days (120 mm) Wet | 10.4h Excellent | 73% Muggy | 6.7 High | Good | View Details |
| June best | 26°C / 17°C | 27°C / 16°C | 11days (101 mm) Wet | 12h Excellent | 71% Muggy | 7.1 Very High | Excellent | View Details |
| July best | 28°C / 20°C | 30°C / 21°C | 11days (92 mm) Wet | 12.2h Excellent | 74% Muggy | 7 High | Excellent | View Details |
| August best | 27°C / 19°C | 29°C / 20°C | 10days (78 mm) Wet | 11.5h Excellent | 73% Muggy | 6.6 High | Excellent | View Details |
| September best | 24°C / 17°C | 25°C / 16°C | 9days (67 mm) Wet | 9.7h Good | 71% Muggy | 5.3 High | Excellent | View Details |
| October | 17°C / 10°C | 15°C / 7°C | 11days (105 mm) Wet | 7.6h Good | 69% Muggy | 3.8 Moderate | Good | View Details |
| November | 9°C / 3°C | 5°C / -2°C | 8days (57 mm) Wet | 6.1h Fair | 69% Muggy | 2.6 Moderate | Poor | View Details |
| December | 4°C / -3°C | -1°C / -8°C | 8days (60 mm) Wet | 5.1h Fair | 72% Muggy | 1.8 Low | Poor | View Details |
Compare Nearby City Climates
Frequently Asked Questions
The best months to visit River Forest are June, July, August, September, when temperatures are comfortable and rainfall is at its lowest. This is based on 10-year climate averages for River Forest, scoring temperature, rainfall, humidity, and sunshine hours.
The hottest month in River Forest is July, with average daytime highs of 28°C (82°F). Plan outdoor activities for early morning or late afternoon if visiting during this period.
The coldest month in River Forest is January, with average overnight lows of -6°C (21°F). Pack warm layers and expect shorter daylight hours during this period.
The wettest month in River Forest is May, averaging 120mm of precipitation across 13 rainy days. An umbrella or waterproof jacket is essential.
The rainy season in River Forest runs through April, May, March, June, with the heaviest rainfall in April. Based on 10-year averages for River Forest.
River Forest receives approximately 104 sunshine hours per year. The sunniest month is July with around 12 hours. Based on climate data for River Forest.
The least favorable months to visit River Forest are January, February, March, December, primarily due to very cold temperatures. For the best conditions, consider June, July, August, September instead.
The annual average UV index in River Forest is 5, classified as moderate. Standard sun protection (sunscreen, hat) is recommended during prolonged outdoor exposure.
Average humidity in River Forest is 71%, classified as moderate. Humidity levels are generally comfortable and should not affect outdoor activities for most people.
Yes, River Forest receives snow. Months with snowfall average 6 snow days and 10 cm (4 in) of accumulation, with about 16 frost days during winter.
Average wind speeds in River Forest are 22 km/h (14 mph). The windiest month is February with peak winds reaching 25 km/h (15 mph) (gusts up to 44 km/h / 28 mph).
River Forest averages 4 clear-sky days per month with overall cloud cover around 61%. The clearest skies occur in September.
The annual average dew point in River Forest is 6°C (43°F), which feels dry and comfortable. Outdoor activities are comfortable year-round from a humidity standpoint.
River Forest has a Humid Subtropical climate, classified as Cfa under the Köppen system. Temperate climates have mild winters and warm summers, with rainfall spread across the year and four distinct seasons.
The 'feels like' temperature in River Forest ranges from 4°C (39°F) to 13°C (55°F) on average. Wind chill makes winters feel noticeably colder than the actual temperature — layered clothing is recommended.
Yes, June is a great time to visit River Forest. It earns a climate score of 8.4/10 with Excellent.
For June in River Forest, pack Umbrella, Waterproof jacket, Breathable clothing, Sunscreen (SPF 30+), Sun hat. With average highs of 26°C (78°F) and 11 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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