McHenry, Illinois Weather
Solstice approaches — longest light. Day 88 of spring. Read this microseason across nine climate regions →
McHenry weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 15Overcast——73°51°—
- TuesdayJun 16Thunderstorm21%—70°57°-3°
- WednesdayJun 17Thunderstorm97%0.90″72°52°+2°
- ThursdayJun 18Light Drizzle69%0.01″65°54°-7°
- FridayJun 19Overcast——66°49°+1°
- SaturdayJun 20Light Drizzle10%0.01″68°52°+2°
- SundayJun 21Drizzle37%0.14″67°54°-1°
AQI 26 (Good), driven by Ozone. AQI flat over the last 6 hours (within ±3 points). Ozone at AQI 32 now. With UV 6.6 peaking around 1 PM under partly cloudy skies, surface ozone likely climbs to AQI 20 around 1 PM.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion during the projected peak around 9 PM.
What's driving it
Ozone × UV × Sky
Ozone at AQI 32 now. With UV 6.6 peaking around 1 PM under partly cloudy skies, surface ozone likely climbs to AQI 20 around 1 PM.
- Present
- AQI 32
- UV peak
- 6.6 at 1 PM
- Sky at peak
- partly cloudy
- Projected peak
- AQI 20
PM × Wind × Precip
PM2.5 at 4.8 µg/m³, PM10 at 4.9 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.98
- Wind
- breezy
- 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
- 5:15 AM
- Moonset
- 8:50 PM
- In sign
- ♋︎ Cancer
Solstice approaches — longest light
McHenry at a glance
- Today vs. normal: 8°F below the seasonal normal for this latitude
- Last frost: April 30 (climatological average for this latitude)
- Microseason: Jun 11–15
- Planting window: Stake and prune tomato suckers. Watch for squash vine borers.
16-Day Forecast — McHenry
- Mon73°51°2%
- Tue70°57°21%
- Wed72°52°97%
- Thu65°54°69%
- Fri66°49°9%
- Sat68°52°10%
- Sun67°54°37%
- Mon67°51°34%
- Tue72°50°11%
- Wed75°54°12%
- Thu79°58°15%
- Fri85°67°27%
- Sat86°73°29%
- Sun87°75°30%
- Mon79°65°36%
- Tue82°64°47%
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 — McHenry
SPC has placed McHenry 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.
ZIP codes in McHenry
- 60050