Romeoville weather in January
In January, Romeoville sees average daytime highs of 31°F and overnight lows near 18°F, with 2.1 in of precipitation across 8.3 wet days and about 9.3 hours of daylight. It is the 12th-warmest and 11th-wettest month of the year here.
Day-to-day highs hold fairly steady near 31°F through the month. The sky is clear or mostly clear about 21% of the time in January, and the air most often feels dry.
Daylight stretches from about 9 hours at the start of January to 9 h 42 min by month's end. Set against the rest of the year, January is Romeoville's 12th-clearest and 3rd-windiest month. For the whole year in context, see Romeoville's year-round climate.
- Daytime high
- 31°
- 12th warmest
- Overnight low
- 18°
- 1st coldest
- Precipitation
- 2.1 in
- 8.3 wet days
- Daylight
- 9 h 18 min
- 7:23 AM – 4:40 PM
- Cloud cover
- 71%
- 12th clearest
- Wind
- 9 mph
- 3rd windiest
- Solar energy
- 1.92 kWh/m²
- Travel score
- 0.0
- out of 10
Romeoville is village in Will County, Illinois, United States.
- Density
- 818/km²
- people per km²
- Founded
- 1895
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Temperature in January
Day-to-day highs hold fairly steady near 31°F through the month.
A typical January day in Romeoville reaches about 31°F in the afternoon and slips back to 18°F overnight — a 13°F spread between the day's warmth and the night's chill. On most days the high lands between 17°F and 45°F. Set against its neighbours, January runs about 5°F cooler than December and about 4°F cooler than February.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°F) | 33 | 33 | 33 | 33 | 33 | 32 | 32 | 32 | 32 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 30 | 30 | 30 | 30 | 30 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 |
| Avg low (°F) | 21 | 20 | 20 | 20 | 20 | 19 | 19 | 19 | 19 | 19 | 18 | 18 | 18 | 18 | 17 | 17 | 17 | 17 | 17 | 17 | 17 | 17 | 17 | 17 | 17 | 17 | 17 | 17 | 18 | 18 | 18 |
| Avg high (°F) | Avg low (°F) | |
|---|---|---|
| 1 | 33 | 21 |
| 2 | 33 | 20 |
| 3 | 33 | 20 |
| 4 | 33 | 20 |
| 5 | 33 | 20 |
| 6 | 32 | 19 |
| 7 | 32 | 19 |
| 8 | 32 | 19 |
| 9 | 32 | 19 |
| 10 | 31 | 19 |
| 11 | 31 | 18 |
| 12 | 31 | 18 |
| 13 | 31 | 18 |
| 14 | 31 | 18 |
| 15 | 31 | 17 |
| 16 | 31 | 17 |
| 17 | 31 | 17 |
| 18 | 30 | 17 |
| 19 | 30 | 17 |
| 20 | 30 | 17 |
| 21 | 30 | 17 |
| 22 | 30 | 17 |
| 23 | 31 | 17 |
| 24 | 31 | 17 |
| 25 | 31 | 17 |
| 26 | 31 | 17 |
| 27 | 31 | 17 |
| 28 | 31 | 17 |
| 29 | 31 | 18 |
| 30 | 31 | 18 |
| 31 | 31 | 18 |
How January really feels in Romeoville
Once humidity and wind are folded in, January averages 0 days that feel above 90°F and 31 that feel at or below 32°F — the comfort signal a plain temperature reading hides.
The story in January is cold — wind chill drags the overnight "feels like" below the raw low.
Romeoville weather by month
How January compares with the rest of the year at a glance. January is the 12th-warmest and 11th-wettest month here — the current month is highlighted below.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 31° / 18° | 2.1 | 8.3 | 5.9 | 9.3 | 0.0 |
| Feb | 35° / 21° | 2.0 | 7.1 | 4.6 | 10.3 | 0.0 |
| Mar | 47° / 30° | 2.7 | 10.1 | 2.9 | 11.7 | 1.4 |
| Apr | 59° / 40° | 4.4 | 12.2 | 1 | 13.1 | 4.2 |
| May | 69° / 51° | 4.4 | 12.7 | 0 | 14.3 | 5.9 |
| Jun | 79° / 61° | 4.2 | 12.2 | 0 | 15 | 6.2 |
| Jul | 83° / 66° | 3.7 | 11.4 | 0 | 14.7 | 5.8 |
| Aug | 81° / 64° | 3.7 | 10.9 | 0 | 13.7 | 6.5 |
| Sep | 74° / 56° | 2.9 | 8.3 | 0 | 12.3 | 7.1 |
| Oct | 62° / 44° | 3.1 | 9.1 | 0.1 | 10.9 | 5.3 |
| Nov | 48° / 33° | 2.5 | 8.3 | 1.3 | 9.7 | 1.7 |
| Dec | 36° / 24° | 2.2 | 8 | 4.2 | 9 | 0.0 |
Cloud cover in January
The sky is clear or mostly clear about 21% of the time in January, the cloudiest month of the year.
Beyond those clear spells, partly cloudy skies cover about 11% of January, with mostly cloudy or overcast conditions the remaining 68%.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 31 | 31 | 31 | 31 | 30 | 30 | 30 | 29 | 30 | 31 | 31 | 31 | 31 | 32 | 32 | 32 | 32 | 33 | 33 | 32 | 32 | 32 | 32 | 33 | 33 | 32 | 31 | 31 | 31 | 31 | 31 |
| Cloudier (%) | 69 | 69 | 69 | 69 | 70 | 70 | 70 | 71 | 70 | 69 | 69 | 69 | 69 | 68 | 68 | 68 | 68 | 67 | 67 | 68 | 68 | 68 | 68 | 67 | 67 | 68 | 69 | 69 | 69 | 69 | 69 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| 1 | 31 | 69 |
| 2 | 31 | 69 |
| 3 | 31 | 69 |
| 4 | 31 | 69 |
| 5 | 30 | 70 |
| 6 | 30 | 70 |
| 7 | 30 | 70 |
| 8 | 29 | 71 |
| 9 | 30 | 70 |
| 10 | 31 | 69 |
| 11 | 31 | 69 |
| 12 | 31 | 69 |
| 13 | 31 | 69 |
| 14 | 32 | 68 |
| 15 | 32 | 68 |
| 16 | 32 | 68 |
| 17 | 32 | 68 |
| 18 | 33 | 67 |
| 19 | 33 | 67 |
| 20 | 32 | 68 |
| 21 | 32 | 68 |
| 22 | 32 | 68 |
| 23 | 32 | 68 |
| 24 | 33 | 67 |
| 25 | 33 | 67 |
| 26 | 32 | 68 |
| 27 | 31 | 69 |
| 28 | 31 | 69 |
| 29 | 31 | 69 |
| 30 | 31 | 69 |
| 31 | 31 | 69 |
Chance of precipitation in January
Romeoville gets around 2.1 in of rain and snow over 8.3 wet days in January. The line is the day-by-day chance of measurable precipitation.
Day to day, the chance of measurable precipitation averages around 26% and peaks near 28% on the wettest days, and about 6 days bring snow.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain chance (%) | 26 | 26 | 27 | 27 | 28 | 28 | 28 | 28 | 28 | 28 | 28 | 28 | 28 | 28 | 28 | 27 | 27 | 27 | 27 | 26 | 26 | 26 | 25 | 25 | 25 | 24 | 24 | 24 | 23 | 23 | 23 |
| Snow chance (%) | 16 | 16 | 17 | 17 | 18 | 18 | 18 | 19 | 19 | 19 | 19 | 19 | 19 | 19 | 19 | 19 | 19 | 19 | 20 | 20 | 20 | 20 | 20 | 19 | 19 | 19 | 19 | 19 | 19 | 19 | 18 |
| Rain chance (%) | Snow chance (%) | |
|---|---|---|
| 1 | 26 | 16 |
| 2 | 26 | 16 |
| 3 | 27 | 17 |
| 4 | 27 | 17 |
| 5 | 28 | 18 |
| 6 | 28 | 18 |
| 7 | 28 | 18 |
| 8 | 28 | 19 |
| 9 | 28 | 19 |
| 10 | 28 | 19 |
| 11 | 28 | 19 |
| 12 | 28 | 19 |
| 13 | 28 | 19 |
| 14 | 28 | 19 |
| 15 | 28 | 19 |
| 16 | 27 | 19 |
| 17 | 27 | 19 |
| 18 | 27 | 19 |
| 19 | 27 | 20 |
| 20 | 26 | 20 |
| 21 | 26 | 20 |
| 22 | 26 | 20 |
| 23 | 25 | 20 |
| 24 | 25 | 19 |
| 25 | 25 | 19 |
| 26 | 24 | 19 |
| 27 | 24 | 19 |
| 28 | 24 | 19 |
| 29 | 23 | 19 |
| 30 | 23 | 19 |
| 31 | 23 | 18 |
Humidity in January
Most of January feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
By dew point, January lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 |
| Dry (%) | |
|---|---|
| 1 | 100 |
| 2 | 100 |
| 3 | 100 |
| 4 | 100 |
| 5 | 100 |
| 6 | 100 |
| 7 | 100 |
| 8 | 100 |
| 9 | 100 |
| 10 | 100 |
| 11 | 100 |
| 12 | 100 |
| 13 | 100 |
| 14 | 100 |
| 15 | 100 |
| 16 | 100 |
| 17 | 100 |
| 18 | 100 |
| 19 | 100 |
| 20 | 100 |
| 21 | 100 |
| 22 | 100 |
| 23 | 100 |
| 24 | 100 |
| 25 | 100 |
| 26 | 100 |
| 27 | 100 |
| 28 | 100 |
| 29 | 100 |
| 30 | 100 |
| 31 | 100 |
Wind in January
Winds average 9 mph in January.
Across January, daily wind ranges from about 9 mph on the calmest days to 9 mph at its breeziest. It stays fairly steady from day to day.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (mph) | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 |
| Feels | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze | light breeze |
| Wind speed (mph) | Feels | |
|---|---|---|
| 1 | 9 | light breeze |
| 2 | 9 | light breeze |
| 3 | 9 | light breeze |
| 4 | 9 | light breeze |
| 5 | 9 | light breeze |
| 6 | 9 | light breeze |
| 7 | 9 | light breeze |
| 8 | 9 | light breeze |
| 9 | 9 | light breeze |
| 10 | 9 | light breeze |
| 11 | 9 | light breeze |
| 12 | 9 | light breeze |
| 13 | 9 | light breeze |
| 14 | 9 | light breeze |
| 15 | 9 | light breeze |
| 16 | 9 | light breeze |
| 17 | 9 | light breeze |
| 18 | 9 | light breeze |
| 19 | 9 | light breeze |
| 20 | 9 | light breeze |
| 21 | 9 | light breeze |
| 22 | 9 | light breeze |
| 23 | 9 | light breeze |
| 24 | 9 | light breeze |
| 25 | 9 | light breeze |
| 26 | 9 | light breeze |
| 27 | 9 | light breeze |
| 28 | 9 | light breeze |
| 29 | 9 | light breeze |
| 30 | 9 | light breeze |
| 31 | 9 | light breeze |
Sunrise & sunset in January
Daylight runs from about 9 hours at the start of January to 9 h 42 min by month's end. The lit band spans sunrise to sunset each day.
Days grow by about 42 minutes over January. Sunrise moves from 7:25 AM to 7:13 AM, and sunset from 4:26 PM to 4:58 PM.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 9.0 | 9.0 | 9.1 | 9.1 | 9.1 | 9.1 | 9.1 | 9.1 | 9.1 | 9.2 | 9.2 | 9.2 | 9.2 | 9.2 | 9.3 | 9.3 | 9.3 | 9.3 | 9.4 | 9.4 | 9.4 | 9.5 | 9.5 | 9.5 | 9.5 | 9.6 | 9.6 | 9.6 | 9.7 | 9.7 | 9.7 |
| Sunrise (AM) | 7:25 | 7:25 | 7:25 | 7:25 | 7:25 | 7:25 | 7:25 | 7:25 | 7:25 | 7:24 | 7:24 | 7:24 | 7:24 | 7:24 | 7:23 | 7:23 | 7:22 | 7:22 | 7:21 | 7:21 | 7:20 | 7:20 | 7:19 | 7:19 | 7:18 | 7:17 | 7:17 | 7:16 | 7:15 | 7:14 | 7:13 |
| Sunset (PM) | 4:26 | 4:27 | 4:28 | 4:29 | 4:30 | 4:31 | 4:31 | 4:32 | 4:33 | 4:34 | 4:35 | 4:36 | 4:37 | 4:38 | 4:39 | 4:40 | 4:42 | 4:43 | 4:44 | 4:45 | 4:46 | 4:47 | 4:48 | 4:50 | 4:51 | 4:52 | 4:53 | 4:54 | 4:56 | 4:57 | 4:58 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| 1 | 9.0 | 7:25 | 4:26 |
| 2 | 9.0 | 7:25 | 4:27 |
| 3 | 9.1 | 7:25 | 4:28 |
| 4 | 9.1 | 7:25 | 4:29 |
| 5 | 9.1 | 7:25 | 4:30 |
| 6 | 9.1 | 7:25 | 4:31 |
| 7 | 9.1 | 7:25 | 4:31 |
| 8 | 9.1 | 7:25 | 4:32 |
| 9 | 9.1 | 7:25 | 4:33 |
| 10 | 9.2 | 7:24 | 4:34 |
| 11 | 9.2 | 7:24 | 4:35 |
| 12 | 9.2 | 7:24 | 4:36 |
| 13 | 9.2 | 7:24 | 4:37 |
| 14 | 9.2 | 7:24 | 4:38 |
| 15 | 9.3 | 7:23 | 4:39 |
| 16 | 9.3 | 7:23 | 4:40 |
| 17 | 9.3 | 7:22 | 4:42 |
| 18 | 9.3 | 7:22 | 4:43 |
| 19 | 9.4 | 7:21 | 4:44 |
| 20 | 9.4 | 7:21 | 4:45 |
| 21 | 9.4 | 7:20 | 4:46 |
| 22 | 9.5 | 7:20 | 4:47 |
| 23 | 9.5 | 7:19 | 4:48 |
| 24 | 9.5 | 7:19 | 4:50 |
| 25 | 9.5 | 7:18 | 4:51 |
| 26 | 9.6 | 7:17 | 4:52 |
| 27 | 9.6 | 7:17 | 4:53 |
| 28 | 9.6 | 7:16 | 4:54 |
| 29 | 9.7 | 7:15 | 4:56 |
| 30 | 9.7 | 7:14 | 4:57 |
| 31 | 9.7 | 7:13 | 4:58 |
Solar energy in January
Average shortwave solar energy reaching the ground each day in January, about 1.92 kWh/m².
For context, solar energy here swings from a low near 1.63 kWh/m² to a high of 6.42 kWh/m² in June across the year — January's 1.92 kWh/m² sits near the bottom.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 1.6 | 1.6 | 1.7 | 1.7 | 1.7 | 1.7 | 1.7 | 1.7 | 1.8 | 1.8 | 1.8 | 1.8 | 1.9 | 1.9 | 1.9 | 1.9 | 1.9 | 2.0 | 2.0 | 2.0 | 2.1 | 2.1 | 2.1 | 2.1 | 2.2 | 2.2 | 2.2 | 2.3 | 2.3 | 2.3 | 2.4 |
| Level | Dim | Dim | Dim | Dim | Dim | Dim | Dim | Dim | Dim | Dim | Dim | Dim | Dim | Dim | Dim | Dim | Dim | Dim | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| 1 | 1.6 | Dim |
| 2 | 1.6 | Dim |
| 3 | 1.7 | Dim |
| 4 | 1.7 | Dim |
| 5 | 1.7 | Dim |
| 6 | 1.7 | Dim |
| 7 | 1.7 | Dim |
| 8 | 1.7 | Dim |
| 9 | 1.8 | Dim |
| 10 | 1.8 | Dim |
| 11 | 1.8 | Dim |
| 12 | 1.8 | Dim |
| 13 | 1.9 | Dim |
| 14 | 1.9 | Dim |
| 15 | 1.9 | Dim |
| 16 | 1.9 | Dim |
| 17 | 1.9 | Dim |
| 18 | 2.0 | Dim |
| 19 | 2.0 | Moderate |
| 20 | 2.0 | Moderate |
| 21 | 2.1 | Moderate |
| 22 | 2.1 | Moderate |
| 23 | 2.1 | Moderate |
| 24 | 2.1 | Moderate |
| 25 | 2.2 | Moderate |
| 26 | 2.2 | Moderate |
| 27 | 2.2 | Moderate |
| 28 | 2.3 | Moderate |
| 29 | 2.3 | Moderate |
| 30 | 2.3 | Moderate |
| 31 | 2.4 | Moderate |
Is January a good time to visit Romeoville?
Our two travel scores rate January for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).
January is a weaker month for outdoor sightseeing in Romeoville.
What to pack for Romeoville in January
From January's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In January, Romeoville sees daytime highs around 31°F and nights near 18°F. Pack a warm layer and a heavy coat. Worth having: rain gear. About 8 days see rain.
Sea temperature near Romeoville in January
The nearest coast averages about 38°F in January — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea at the nearest coast (about 29 mi away) is warmest in August at about 73°F and coldest in February near 36°F.
It's comfortable for a long swim from Jul 13 to Sep 15 — about 2.1 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 | 39 | 45 | 57 | 70 | 73 | 68 | 58 | 49 | 42 |
| Comfort | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Refreshing | Refreshing | Refreshing | Bracing | Bracing | Bracing |
| Sea temperature (°F) | Comfort | |
|---|---|---|
| Jan | 38 | Bracing |
| Feb | 36 | Bracing |
| Mar | 36 | Bracing |
| Apr | 39 | Bracing |
| May | 45 | Bracing |
| Jun | 57 | Bracing |
| Jul | 70 | Refreshing |
| Aug | 73 | Refreshing |
| Sep | 68 | Refreshing |
| Oct | 58 | Bracing |
| Nov | 49 | Bracing |
| Dec | 42 | Bracing |
UV index in Romeoville in January
Clear-sky midday UV in January peaks around 2. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Romeoville peaks around June 22 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 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 | 7 | 9 | 9 | 8 | 6 | 3 | 2 | 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 | 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 | 2 | Low |
Air quality in Romeoville in January
Average fine-particle pollution (PM2.5) through the year — so you can see where January falls, not just the annual average.
Air quality in Romeoville 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 Romeoville?
Romeoville sits at 41.6°N, 88.1°W, 620 ft above sea level, in United States. The nearest listed city is Bolingbrook, 3.7 mi away.
Topography around Romeoville
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Romeoville.
Within 2 miles, the terrain around Romeoville has only modest variations in elevation — a maximum elevation change of 167 ft around an average of 636 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 427 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 751 ft.
The land around Romeoville is covered by artificial surfaces (46%) and grassland (25%) within 2 miles, trees (34%), artificial surfaces (26%) and grassland (25%) within 10 miles, and cropland (46%) 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 Romeoville (41.6475°, -88.0895°, elevation 620 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. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).