Rosemont in Summer
In summer (June, July and August), Rosemont sees average daytime highs around 90°F and overnight lows near 61°F, with 0.3 in of rain over about 1 wet days across the season. It is the warmest season of the year and the driest season of the year.
Over the season highs climb from about 85°F in early June to 90°F by late August. The sky is clear or mostly clear about 86% of the time across summer, and the air most often feels dry.
Summer is Rosemont's 3rd-best season to visit on our travel score. For the whole year in context, see Rosemont's year-round climate.
- Avg daytime high
- 90°F
- warmest season of the year
- Avg overnight low
- 61°F
- Rainfall
- 0.3 in
- 1 wet days
- Avg wind
- 5 mph
- Travel score
- 5.2
- 3rd-best season
- Months
- Jun · Jul · Aug
Temperature in Rosemont in Summer
Over the season highs climb from about 85°F in early June to 90°F by late August.
A typical summer day in Rosemont reaches about 90°F and drops to 61°F overnight. The warmest of the three months is July, the coolest June.
How summer really feels in Rosemont
Once humidity and wind are folded in, summer brings about 71 days that feel above 90°F and 0 that feel at or below 32°F.
The story in summer is heat — humidity pushes the afternoon "feels like" well above the raw temperature.
Rosemont 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 | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 57° / 41° | 4.9 | 9.5 | 9.6 | 4.2 |
| Feb | 62° / 43° | 4.7 | 9.6 | 10.5 | 5.2 |
| Mar | 66° / 46° | 4.1 | 9.2 | 11.7 | 6.3 |
| Apr | 72° / 50° | 1.9 | 5.8 | 13 | 7.5 |
| May | 80° / 55° | 1.1 | 4 | 14.1 | 7.7 |
| Jun | 88° / 59° | 0.2 | 1 | 14.6 | 5.9 |
| Jul | 91° / 62° | 0.0 | 0.1 | 14.4 | 4.8 |
| Aug | 91° / 61° | 0.1 | 0.2 | 13.5 | 5.0 |
| Sep | 87° / 59° | 0.1 | 0.7 | 12.3 | 6.4 |
| Oct | 78° / 53° | 1.4 | 3.2 | 11 | 8.3 |
| Nov | 65° / 45° | 2.6 | 6.6 | 9.9 | 6.5 |
| Dec | 57° / 40° | 4.8 | 9.7 | 9.4 | 4.1 |
Cloud cover in Summer
The sky is clear or mostly clear about 86% of the time across summer.
Chance of precipitation in Summer
Rosemont gets around 0.3 in of rain over 1 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 5 mph across summer.
Sunrise & sunset in Summer
Daylight runs from about 14 h 30 min in early June to 12 h 54 min 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 7.9 kWh/m².
Hazard calendar for Rosemont
None of Rosemont's seasonal hazards peak in summer. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do.
Rosemont's rainy season runs November–March, when most of the year's rain falls.
Is summer a good time to visit Rosemont?
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 Rosemont for sightseeing. The water and warmth also suit a beach or pool day.
What to pack for Rosemont in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Rosemont sees daytime highs around 90°F and nights near 61°F. Pack light clothes and sun protection.
UV index in Rosemont in Summer
Clear-sky midday UV across summer averages around 10 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Rosemont peaks around June 21 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 14 at about 2 (moderate).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 2 | 3 | 4 | 6 | 8 | 10 | 10 | 9 | 6 | 5 | 2 | 2 |
| Level | Moderate | Moderate | Moderate | High | Very high | Very high | Very high | Very high | High | Moderate | Moderate | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 2 | Moderate |
| Feb | 3 | Moderate |
| Mar | 4 | Moderate |
| Apr | 6 | High |
| May | 8 | Very high |
| Jun | 10 | Very high |
| Jul | 10 | Very high |
| Aug | 9 | Very high |
| Sep | 6 | High |
| Oct | 5 | Moderate |
| Nov | 2 | Moderate |
| Dec | 2 | Low |
Air quality in Rosemont 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 Rosemont is worst in August — around 27 µg/m³ PM2.5 (moderate), about 3.6× the cleanest month (June, 8 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) | 15 | 14 | 15 | 12 | 9 | 8 | 11 | 27 | 23 | 17 | 19 | 14 |
| Level | Moderate | Moderate | Moderate | Good | Good | Good | Good | Moderate | Moderate | Moderate | Moderate | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 15 | Moderate |
| Feb | 14 | Moderate |
| Mar | 15 | Moderate |
| Apr | 12 | Good |
| May | 9 | Good |
| Jun | 8 | Good |
| Jul | 11 | Good |
| Aug | 27 | Moderate |
| Sep | 23 | Moderate |
| Oct | 17 | Moderate |
| Nov | 19 | Moderate |
| Dec | 14 | Moderate |
Where is Rosemont?
Rosemont sits at 38.6°N, 121.4°W, 49 ft above sea level, in United States. The nearest listed city is Arden-Arcade, 3.7 mi away.
Topography around Rosemont
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Rosemont.
Within 2 miles, the terrain around Rosemont has only modest variations in elevation — a maximum elevation change of 108 ft around an average of 52 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 328 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 5,384 ft.
The land around Rosemont is covered by artificial surfaces (51%) and trees (20%) within 2 miles, artificial surfaces (43%), grassland (28%) and trees (20%) within 10 miles, and trees (34%), grassland (31%) and cropland (23%) 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 Rosemont (38.5519°, -121.3647°, elevation 49 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.