Illinois · NWS LOT office

Algonquin, IL weather

It is 55°F and cloudy at Chicago / West Chicago, Dupage Airport as of Oct 28, 1:15 AM CDT. Overnight: Partly Cloudy, low near 50°F, 1% chance of precipitation. Forecast from the National Weather Service, issued Oct 28, 1:20 AM CDT.

Updated Oct 28, 1:27 AM CDT (snapshot)

Current conditions

Temperature

55°F

Cloudy

Wind

SSE 5 mph

Humidity 77% · dew point 48°F

Pressure · visibility

30.19 inHg

Visibility 10 mi

Observed at Chicago / West Chicago, Dupage Airport (KDPA), Oct 28, 1:15 AM CDT. Station readings can lag or be missing.

Alerts for this area

No active NWS alerts cover the Algonquin forecast zone right now.

Around the NWS LOT forecast area

No active alerts in zones served by the LOT office near Algonquin.

From the alert snapshot of Oct 28, 2026, 2:15 AM EDT. No alerts are active anywhere in Illinois.

For official warnings, check weather.gov and your local authorities. OpenForecast repeats National Weather Service alerts and may be delayed or incomplete. Follow instructions from emergency officials.

Next 24 hours

Hourly forecast for Algonquin (local time)
TimeTempForecastPrecip. chanceWind
Wed 1 AM55°FMostly Cloudy0%S 5 mph
Wed 2 AM54°FPartly Cloudy0%S 5 mph
Wed 3 AM52°FMostly Clear0%S 5 mph
Wed 4 AM51°FMostly Clear0%S 5 mph
Wed 5 AM51°FMostly Clear0% 0 mph
Wed 6 AM50°FSunny0% 0 mph
Wed 7 AM50°FSunny0% 0 mph
Wed 8 AM51°FSunny0% 0 mph
Wed 9 AM55°FSunny0%S 5 mph
Wed 10 AM60°FSunny0%SSW 10 mph
Wed 11 AM64°FSunny0%SSW 10 mph
Wed 12 PM67°FSunny0%S 10 mph
Wed 1 PM70°FSunny0%S 10 mph
Wed 2 PM71°FSunny0%SSW 15 mph
Wed 3 PM72°FSunny0%SSW 15 mph
Wed 4 PM72°FSunny0%SSW 15 mph
Wed 5 PM71°FSunny0%S 10 mph
Wed 6 PM68°FMostly Clear0%S 10 mph
Wed 7 PM65°FMostly Clear0%S 10 mph
Wed 8 PM64°FMostly Clear0%S 10 mph
Wed 9 PM63°FMostly Clear0%S 10 mph
Wed 10 PM63°FMostly Clear0%S 10 mph
Wed 11 PM62°FPartly Cloudy1%S 10 mph
Thu 12 AM62°FPartly Cloudy1%SSW 15 mph

Hourly values come from the NWS gridded forecast for the 2.5 km grid square that covers the city's center point. Conditions elsewhere in Algonquin can differ.

7-day forecast

Overnight

Low 50°F

Partly cloudy, with a low around 50. South wind around 5 mph.

Wednesday

High 72°F·Low 58°F

Sunny. High near 72, with temperatures falling to around 70 in the afternoon. South southwest wind 0 to 15 mph, with gusts as high as 25 mph.

Wednesday Night: A chance of rain showers after 3am. Partly cloudy, with a low around 58. South southwest wind 10 to 15 mph. Chance of precipitation is 30%.

Thursday

High 69°F·Low 42°F

A chance of rain showers before 8am. Mostly sunny, with a high near 69. West wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 30%.

Thursday Night: Mostly clear, with a low around 42. North wind 0 to 5 mph.

Friday

High 63°F·Low 48°F

Partly sunny, with a high near 63.

Friday Night: A chance of rain showers between 7pm and 1am, then a chance of showers and thunderstorms. Cloudy, with a low around 48.

Saturday

High 61°F·Low 49°F

A chance of showers and thunderstorms. Mostly cloudy, with a high near 61.

Saturday Night: A chance of rain showers. Cloudy, with a low around 49.

Sunday

High 66°F·Low 51°F

A chance of rain showers. Mostly cloudy, with a high near 66.

Sunday Night: A chance of rain showers. Mostly cloudy, with a low around 51.

Monday

High 66°F·Low 52°F

A chance of rain showers. Mostly cloudy, with a high near 66.

Monday Night: A chance of rain showers. Mostly cloudy, with a low around 52.

Tuesday

High 65°F

Rain showers likely. Mostly cloudy, with a high near 65.

Nearby cities

Larger cities in the area

Other cities in McHenry County

See every city we cover in Illinois, or check all active alerts.

About this forecast

Forecast office
Algonquin is served by the National Weather Service LOT forecast office, forecast zone ILZ005, county zone ILC111.
Location used
The Census Bureau's internal point for Algonquin (42.1595, -88.3219), in McHenry County. Population: 30,539 (2024 estimate), number 65 of the 121 Illinois cities on this site.
Radar
Nearest NWS radar: KLOT. View it on radar.weather.gov.

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Sources

  • Forecast, hourly forecast, observations and alerts: National Weather Service API, api.weather.gov/points/42.1595,-88.3219 (forecast issued Oct 28, 1:20 AM CDT).
  • Official forecast page: forecast.weather.gov.
  • City location and population: U.S. Census Bureau, Vintage 2024 population estimates and 2024 Gazetteer files.
  • Snapshot taken Oct 28, 2026. The NWS and Census Bureau do not endorse OpenForecast.

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