Round Lake in Fall
In fall (September, October and November), Round Lake sees average daytime highs around 59°F and overnight lows near 47°F, with 8.8 in of precipitation over about 27 wet days across the season. It is the 2nd-warmest season and the 3rd-wettest season.
Over the season highs ease from about 76°F in early September to 41°F by late November. The sky is clear or mostly clear about 33% of the time across fall, and the air most often feels dry.
Fall is Round Lake's 2nd-best season to visit on our travel score. For the whole year in context, see Round Lake's year-round climate.
- Avg daytime high
- 59°F
- 2nd-warmest season
- Avg overnight low
- 47°F
- Precipitation
- 8.8 in
- 27 wet days
- Avg wind
- 10 mph
- Travel score
- 4.4
- 2nd-best season
- Months
- Sep · Oct · Nov
Temperature in Round Lake in Fall
Over the season highs ease from about 76°F in early September to 41°F by late November.
A typical fall day in Round Lake reaches about 59°F and drops to 47°F overnight. The warmest of the three months is September, the coolest November.
How fall really feels in Round Lake
Once humidity and wind are folded in, fall brings about 0 days that feel above 90°F and 26 that feel at or below 32°F.
The story in fall is cold — wind chill drags the overnight "feels like" below the raw low.
Round Lake weather by month
How the three fall months (September, October and November) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 30° / 19° | 2.3 | 9.1 | 6.4 | 9.3 | 0.0 |
| Feb | 33° / 20° | 2.0 | 7.2 | 5.3 | 10.3 | 0.0 |
| Mar | 42° / 29° | 2.6 | 9.7 | 3.2 | 11.6 | 0.6 |
| Apr | 53° / 40° | 4.4 | 12.2 | 1.2 | 13.1 | 2.9 |
| May | 64° / 51° | 4.1 | 12.3 | 0 | 14.4 | 5.3 |
| Jun | 76° / 62° | 3.6 | 11.4 | 0 | 15 | 6.5 |
| Jul | 80° / 67° | 3.3 | 10.8 | 0 | 14.8 | 6.4 |
| Aug | 79° / 66° | 3.6 | 10.7 | 0 | 13.7 | 6.7 |
| Sep | 72° / 58° | 2.9 | 9 | 0 | 12.3 | 6.9 |
| Oct | 60° / 46° | 3.3 | 9.5 | 0.1 | 10.8 | 4.8 |
| Nov | 46° / 35° | 2.6 | 8.5 | 1.4 | 9.6 | 1.4 |
| Dec | 35° / 25° | 2.4 | 8.8 | 4.5 | 9 | 0.0 |
Cloud cover in Fall
The sky is clear or mostly clear about 33% of the time across fall.
Chance of precipitation in Fall
Round Lake gets around 8.8 in of rain and snow over 27 wet days across fall. The line is the day-by-day chance of measurable precipitation.
Humidity in Fall
Most of fall feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Fall
Winds average 10 mph across fall.
Sunrise & sunset in Fall
Daylight runs from about 13 hours in early September to 9 h 12 min by late November. The lit band spans sunrise to sunset each day.
Solar energy in Fall
Average shortwave solar energy reaching the ground each day across fall, about 3.1 kWh/m².
Is fall a good time to visit Round Lake?
Our two travel scores rate fall for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
fall is a reasonable time to visit Round Lake for sightseeing.
What to pack for Round Lake in Fall
From fall's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In fall, Round Lake sees daytime highs around 59°F and nights near 47°F. Pack a warm layer. Worth having: light clothes, a heavy coat and rain gear. About 27 days see rain.
Sea temperature near Round Lake in Fall
The nearest coast averages about 57°F across fall — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea at the nearest coast (about 11 mi away) is warmest in August at about 71°F and coldest in March near 36°F.
It's comfortable for a long swim from Jul 18 to Sep 8 — about 1.7 months when the water holds above 68°F.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°F) | 38 | 36 | 36 | 38 | 43 | 55 | 68 | 71 | 67 | 57 | 47 | 42 |
| Comfort | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Refreshing | Refreshing | Cool | Bracing | Bracing | Bracing |
| Sea temperature (°F) | Comfort | |
|---|---|---|
| Jan | 38 | Bracing |
| Feb | 36 | Bracing |
| Mar | 36 | Bracing |
| Apr | 38 | Bracing |
| May | 43 | Bracing |
| Jun | 55 | Bracing |
| Jul | 68 | Refreshing |
| Aug | 71 | Refreshing |
| Sep | 67 | Cool |
| Oct | 57 | Bracing |
| Nov | 47 | Bracing |
| Dec | 42 | Bracing |
UV index in Round Lake in Fall
Clear-sky midday UV across fall averages around 4 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Round Lake peaks around June 22 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 at about 1 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 1 | 2 | 4 | 6 | 7 | 9 | 9 | 8 | 6 | 3 | 2 | 1 |
| Level | Low | Moderate | Moderate | High | Very high | Very high | Very high | Very high | High | Moderate | Moderate | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 1 | Low |
| Feb | 2 | Moderate |
| Mar | 4 | Moderate |
| Apr | 6 | High |
| May | 7 | Very high |
| Jun | 9 | Very high |
| Jul | 9 | Very high |
| Aug | 8 | Very high |
| Sep | 6 | High |
| Oct | 3 | Moderate |
| Nov | 2 | Moderate |
| Dec | 1 | Low |
Air quality in Round Lake in Fall
Average fine-particle pollution (PM2.5) through the year — so you can see where fall falls, not just the annual average.
Air quality in Round Lake is worst in July — around 21 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (October, 10 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 12 | 15 | 18 | 19 | 20 | 21 | 21 | 18 | 15 | 10 | 10 | 11 |
| Level | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 12 | Moderate |
| Feb | 15 | Moderate |
| Mar | 18 | Moderate |
| Apr | 19 | Moderate |
| May | 20 | Moderate |
| Jun | 21 | Moderate |
| Jul | 21 | Moderate |
| Aug | 18 | Moderate |
| Sep | 15 | Moderate |
| Oct | 10 | Good |
| Nov | 10 | Good |
| Dec | 11 | Good |
Where is Round Lake?
Round Lake sits at 42.4°N, 88.1°W, 797 ft above sea level, in United States. The nearest listed city is Round Lake Beach, 1.2 mi away.
Topography around Round Lake
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Round Lake.
Within 2 miles, the terrain around Round Lake has only modest variations in elevation — a maximum elevation change of 125 ft around an average of 784 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 302 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 827 ft.
The land around Round Lake is covered by trees (31%), grassland (29%) and artificial surfaces (28%) within 2 miles, trees (37%) and grassland (29%) within 10 miles, and water (30%), cropland (26%) and trees (20%) within 50 miles.
United States travel facts
- Power plugs
- Type A / B
- 120 V · 60 Hz
- Prices
- ≈ 100% of US
- price level, 2025
- GDP per capita
- $90,027
- 2025
- Happiness
- 6.8 / 10
- World Happiness, 2025
- Safe drinking water
- 98%
- of population, 2024
- Homicide rate
- 5.8
- per 100k, 2023
- Road deaths
- 12.7
- per 100k/yr, 2019
- Income group
- High
- World Bank
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Round Lake (42.3534°, -88.0934°, elevation 797 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.