Mount Prospect, Illinois Weather
Fireflies rise from the lawn. Day 76 of spring. Read this microseason across nine climate regions →
Mount Prospect weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 3Overcast——83°50°—
- ThursdayJun 4Overcast——88°59°+5°
- FridayJun 5Heavy Drizzle57%0.04″79°68°-9°
- SaturdayJun 6Drizzle57%—84°63°+5°
- SundayJun 7Overcast14%—76°58°-8°
- MondayJun 8Light Drizzle16%—81°62°+5°
- TuesdayJun 9Light Drizzle23%—80°69°-1°
Ozone at AQI 76 now. AQI up 7 over the last 6 hours (gradual rise). With UV 7.3 peaking around 1 PM under partly cloudy skies, surface ozone likely climbs to AQI 52 by mid-afternoon.
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 76 now. With UV 7.3 peaking around 1 PM under partly cloudy skies, surface ozone likely climbs to AQI 52 by mid-afternoon.
- Present
- AQI 76
- UV peak
- 7.3 at 1 PM
- Sky at peak
- partly cloudy
- Projected peak
- AQI 52
PM × Wind × Precip
PM2.5 at 8.0 µg/m³ (AQI 44) with a 0.88 fine-to-coarse ratio and 6 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
- 3:51 AM
- Moonset
- 12:42 PM
- In sign
- ♑︎ Capricorn
Fireflies rise from the lawn
Mount Prospect at a glance
- Today vs. normal: 9°F above the seasonal normal for this latitude
- Last frost: April 28 (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 — Mount Prospect
SPC has placed Mount Prospect in the Marginal Risk category for severe thunderstorms day after tomorrow.
- TODAYNONENo severe risk
- TOMORROWNONENo severe risk
- 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.