Lanark, Illinois Weather
Fireflies rise from the lawn. Day 76 of spring. Read this microseason across nine climate regions →
Lanark weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 3Overcast——83°53°—
- ThursdayJun 4Overcast16%—86°56°+3°
- FridayJun 5Showers63%0.28″76°67°-10°
- SaturdayJun 6Heavy Showers59%1.3″80°64°+4°
- SundayJun 7Overcast19%—80°61°0°
- MondayJun 8Light Drizzle36%0.01″73°65°-7°
- TuesdayJun 9Light Drizzle21%—77°69°+4°
Ozone at AQI 58. AQI flat over the last 6 hours (within ±3 points). Overcast through the UV peak window (cloud cover ~68%) — afternoon ozone should stay flat.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
Ozone × UV × Sky
Ozone at AQI 58. Overcast through the UV peak window (cloud cover ~68%) — afternoon ozone should stay flat.
- Present
- AQI 58
- UV peak
- 8.7 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 34
PM × Wind × Precip
PM2.5 at 5.7 µg/m³ (AQI 32) with a 0.88 fine-to-coarse ratio and 5 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.88
- Wind
- light
- Recent rain
- 0h in last 6h
- Pattern
- stagnant smoke
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).
The higher the clouds, the finer the weather.
- Moonrise
- 3:59 AM
- Moonset
- 12:50 PM
- In sign
- ♑︎ Capricorn
Fireflies rise from the lawn
Lanark at a glance
- Today vs. normal: 7°F above the seasonal normal for this latitude
- Last frost: April 29 (climatological average for this latitude)
- Microseason: Jun 1–5
- Planting window: Harvest spring lettuce before it bolts. Sow heat-tolerant greens.
Right now in the garden
Peak growing season
As of June 3, 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 — Lanark
SPC has placed Lanark in the Marginal Risk category for severe thunderstorms day after tomorrow.
- TODAYNONENo severe risk
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3MRGLMarginal Risk
Isolated severe storms possible. Limited threat for hail or damaging wind.
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.