Sterling in Summer
In summer (June, July and August), Sterling sees average daytime highs around 81°F and overnight lows near 63°F, with 11.5 in of rain over about 31 wet days across the season. It is the warmest season of the year and the 2nd-wettest season.
Across summer, daytime highs hold fairly steady around 81°F. The sky is clear or mostly clear about 36% of the time across summer, and the air most often feels muggy.
Summer is Sterling's best season of the year to visit on our travel score. For the whole year in context, see Sterling's year-round climate.
- Avg daytime high
- 81°F
- warmest season of the year
- Avg overnight low
- 63°F
- Rainfall
- 11.5 in
- 31 wet days
- Avg wind
- 7 mph
- Travel score
- 6.3
- best season of the year
- Months
- Jun · Jul · Aug
Temperature in Sterling in Summer
Across summer, daytime highs hold fairly steady around 81°F.
A typical summer day in Sterling reaches about 81°F and drops to 63°F overnight. The warmest of the three months is July, the coolest June.
How summer really feels in Sterling
Once humidity and wind are folded in, summer brings about 0 days that feel above 90°F and 0 that feel at or below 32°F.
summer sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.
Sterling weather by month
How the three summer months (June, July and August) 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° / 15° | 1.9 | 7.6 | 5.1 | 9.3 | 0.0 |
| Feb | 35° / 19° | 1.9 | 6.7 | 4.2 | 10.3 | 0.0 |
| Mar | 48° / 30° | 2.6 | 9.4 | 2.4 | 11.7 | 1.7 |
| Apr | 60° / 41° | 4.3 | 11.5 | 0.8 | 13.1 | 4.6 |
| May | 71° / 52° | 4.7 | 13.2 | 0 | 14.3 | 6.0 |
| Jun | 80° / 62° | 4.5 | 12 | 0 | 15 | 6.3 |
| Jul | 83° / 65° | 3.7 | 10.1 | 0 | 14.7 | 6.0 |
| Aug | 81° / 63° | 3.3 | 9.1 | 0 | 13.7 | 6.7 |
| Sep | 75° / 55° | 3.4 | 8.3 | 0 | 12.3 | 7.1 |
| Oct | 62° / 43° | 2.9 | 8.5 | 0.2 | 10.9 | 5.5 |
| Nov | 47° / 32° | 2.5 | 7.7 | 1.3 | 9.6 | 1.7 |
| Dec | 35° / 22° | 2.2 | 7.5 | 4 | 9 | 0.0 |
Cloud cover in Summer
The sky is clear or mostly clear about 36% of the time across summer.
Chance of precipitation in Summer
Sterling gets around 11.5 in of rain over 31 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels muggy — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 7 mph across summer.
Sunrise & sunset in Summer
Daylight runs from about 14 h 48 min in early June to 13 hours by late August. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 6.1 kWh/m².
Is summer a good time to visit Sterling?
Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
summer is a reasonable time to visit Sterling for sightseeing. The water and warmth also suit a beach or pool day.
What to pack for Sterling in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Sterling sees daytime highs around 81°F and nights near 63°F. Pack light clothes and sun protection. Worth having: rain gear. About 31 days see rain.
UV index in Sterling in Summer
Clear-sky midday UV across summer averages around 8 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Sterling peaks around June 18 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 19 at about 2 (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) | 2 | 3 | 5 | 6 | 8 | 9 | 8 | 8 | 6 | 4 | 3 | 2 |
| Level | Low | Moderate | Moderate | High | Very high | Very high | Very high | Very high | High | Moderate | Moderate | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 2 | Low |
| Feb | 3 | Moderate |
| Mar | 5 | Moderate |
| Apr | 6 | High |
| May | 8 | Very high |
| Jun | 9 | Very high |
| Jul | 8 | Very high |
| Aug | 8 | Very high |
| Sep | 6 | High |
| Oct | 4 | Moderate |
| Nov | 3 | Moderate |
| Dec | 2 | Low |
Air quality in Sterling in Summer
Average fine-particle pollution (PM2.5) through the year — so you can see where summer falls, not just the annual average.
Air quality in Sterling is worst in July — around 15 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (October, 7 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) | 11 | 13 | 13 | 11 | 13 | 13 | 15 | 14 | 11 | 7 | 8 | 9 |
| Level | Good | Moderate | Moderate | Good | Moderate | Moderate | Moderate | Moderate | Good | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 11 | Good |
| Feb | 13 | Moderate |
| Mar | 13 | Moderate |
| Apr | 11 | Good |
| May | 13 | Moderate |
| Jun | 13 | Moderate |
| Jul | 15 | Moderate |
| Aug | 14 | Moderate |
| Sep | 11 | Good |
| Oct | 7 | Good |
| Nov | 8 | Good |
| Dec | 9 | Good |
Where is Sterling?
Sterling sits at 41.8°N, 89.7°W, 659 ft above sea level, in United States. The nearest listed city is Dixon, 12 mi away.
Topography around Sterling
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Sterling.
Within 2 miles, the terrain around Sterling has only modest variations in elevation — a maximum elevation change of 121 ft around an average of 656 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 295 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 830 ft.
The land around Sterling is covered by trees (28%) and artificial surfaces (28%) within 2 miles, cropland (81%) within 10 miles, and cropland (77%) 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 Sterling (41.7886°, -89.6962°, elevation 659 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.