Old Mill Creek, Illinois Weather
Solstice approaches — longest light. Day 88 of spring. Read this microseason across nine climate regions →
Old Mill Creek weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 15Overcast——74°50°—
- TuesdayJun 16Overcast69%—72°57°-2°
- WednesdayJun 17Thunderstorm89%1.6″70°50°-2°
- ThursdayJun 18Heavy Drizzle72%0.10″68°53°-2°
- FridayJun 19Light Drizzle—0.01″66°49°-2°
- SaturdayJun 20Heavy Drizzle14%0.17″65°53°-1°
- SundayJun 21Overcast31%—68°51°+3°
AQI 29 (Good), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 7.1 µg/m³, PM10 at 7.3 µg/m³ — typical background levels with no transport signature.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
PM × Wind × Precip
PM2.5 at 7.1 µg/m³, PM10 at 7.3 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.97
- Wind
- light
- Recent rain
- 0h in last 6h
- Pattern
- background
Trends
Seven days of AQI and PM2.5.
Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).








































A summer fog for fair, a winter fog for rain.
- Moonrise
- 5:13 AM
- Moonset
- 8:49 PM
- In sign
- ♊︎ Gemini
Solstice approaches — longest light
Old Mill Creek at a glance
- Today vs. normal: 21°F below the seasonal normal for this latitude
- Last frost: May 1 (climatological average for this latitude)
- Microseason: Jun 11–15
- Planting window: Stake and prune tomato suckers. Watch for squash vine borers.
15-Day Forecast — Old Mill Creek
- Mon74°50°2%
- Tue72°57°69%
- Wed70°50°89%
- Thu68°53°72%
- Fri66°49°9%
- Sat65°53°14%
- Sun68°51°31%
- Mon68°51°31%
- Tue72°52°10%
- Wed78°57°19%
- Thu76°58°20%
- Fri78°58°24%
- Sat88°68°29%
- Sun90°75°28%
- Mon80°69°32%
Forecast data from Open-Meteo (CC BY 4.0).
Right now in the garden
Peak growing season
As of June 15, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.
SPC Convective Outlook
Storm Prediction Center — Old Mill Creek
SPC has placed Old Mill Creek in the Slight Risk category for severe thunderstorms day after tomorrow.
- TODAYTSTMGeneral Thunderstorms
- TOMORROWMRGLMarginal Risk
- DAY 3SLGTSlight Risk
Scattered severe storms possible. A few tornadoes, hail, and damaging wind gusts possible.
Source: NOAA / NWS Storm Prediction Center categorical convective outlook. Outlooks are re-issued multiple times per day; this page reflects the most recent SPC polygons covering the city’s coordinates.
Microseason · June 11–15
Solstice approaches — longest light
Sunrise before 5:30 AM; sunset nearly 8:30 PM.
Day 166 of 365 · Wedge 33 of 72
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | — | — |
| April | — | — |
| May | lettuce, peas, spinach, radishes | lettuce, peas, radishes |
| June | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | tomatoes, peppers, beans, squash | tomatoes, beans, summer squash |
| August | tomatoes, peppers, beans, squash, fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| September | fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| October | — | winter squash, tomatoes (last) |
| November | — | — |
| December | — | — |
A year in weather
Old Mill Creek's warmest month is July (~75°F mean) and its coldest is January (~22°F). Rainfall peaks in May (3.7 inches) and bottoms out in January (1.8 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 22° | 1.8″ | 15 |
| February | 24° | 1.9″ | 13 |
| March | 35° | 2.7″ | 15 |
| April | 47° | 3.4″ | 17 |
| May | 57° | 3.7″ | 18 |
| June | 68° | 3.4″ | 15 |
| July | 75° | 2.5″ | 13 |
| August | 74° | 2.8″ | 13 |
| September | 67° | 3.1″ | 14 |
| October | 54° | 2.9″ | 13 |
| November | 39° | 3.2″ | 14 |
| December | 26° | 2.3″ | 13 |
Frequently asked
- When does it freeze in Old Mill Creek?
- In Old Mill Creek, expect the last spring frost near mid-May; Old Mill Creek's first autumn frost comes around mid-October.
- What is the rainy season in Old Mill Creek?
- May is the wettest month in Old Mill Creek, about 3.7 inches on average; the year totals roughly 34 inches.
- What is the warmest month in Old Mill Creek?
- The warmest stretch in Old Mill Creek comes in July, around 75°F on average.
- What is the coldest month in Old Mill Creek?
- On average January is the chilliest month in Old Mill Creek, about 22°F.
- When can I start a vegetable garden in Old Mill Creek?
- Time tomatoes in Old Mill Creek for two weeks after mid-May; peas and greens start at Old Mill Creek's frost line.
- How many rainy days does Old Mill Creek get?
- Expect roughly 173 wet days a year in Old Mill Creek.
- What hardiness zone is Old Mill Creek?
- Old Mill Creek sits in the USDA zone set by January lows near 22°F; the USDA ZIP tool gives the band.
- What is the 10-day forecast for Old Mill Creek?
- Old Mill Creek's extended outlook — daily high and low temperatures and precipitation chances for each upcoming day — is in the daily forecast above.
- Will it rain this week in Old Mill Creek?
- See this week's day-by-day rain chances for Old Mill Creek in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Old Mill Creek?
- Current conditions for Old Mill Creek and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Old Mill Creek forecast updated?
- The Old Mill Creek forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Old Mill Creek?
- Day length in Old Mill Creek peaks around the June solstice — earliest sunrise and latest sunset — and is shortest near the December solstice.
- How accurate is the weather forecast for Old Mill Creek?
- The next few days in Old Mill Creek's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Climate
Old Mill Creek, Illinois has a warm-summer humid continental climate: January averages roughly 22°F, July about 75°F, 53°F between them.
Across the year, Old Mill Creek collects about 34 inches of precipitation over roughly 173 days with measurable rain or snow.
At 42.4°N, Old Mill Creek's 53°F summer-to-winter swing sets when Old Mill Creek's gardens wake and when frost returns.
ZIP codes in Old Mill Creek
- 60083