Chicago, IL 60640 Weather

Cook County12:52 AM CDT41.97°N, 87.66°W

Current conditions

Clear
48°
Clear
Feels like 48°
High 67°·Low 48° tonight
WindCalm
Humidity93%
Dew point46°
Pressure30.29 inHg
Visibility8.0 mi
Cloud cover20%
UV index0 Low
Sunrise7:11 AM
Sunset6:01 PM

Observed at Chicago, Chicago-O'Hare International Airport · 17 min ago

Forecast

10-day

  • Tonight

    Patchy fog after 3am. Partly cloudy. Low around 48, with temperatures rising to around 50 overnight. South southeast wind 0 to 5 mph.

  • Wednesday

    Patchy fog before 8am. Sunny, with a high near 67. South wind 0 to 5 mph.

  • Wednesday Night

    Mostly clear, with a low around 52. South southwest wind 0 to 5 mph.

National Weather Service forecast updated 9 hrs ago.

Hourly

Hourly forecast
  1. Now Mostly Clear 55°
  2. 1 AM Mostly Clear 54°
  3. 2 AM Mostly Clear 53°
  4. 3 AM Patchy Fog 52°
  5. 4 AM Patchy Fog 51°
  6. 5 AM Patchy Fog 50°
  7. 6 AM Patchy Fog 49°
  8. 7 AM Patchy Fog 48°
  9. 8 AM Mostly Sunny 50°
  10. 9 AM Mostly Sunny 53°
  11. 10 AM Mostly Sunny 57°
  12. 11 AM Sunny 60°
  13. 12 PM Sunny 63°
  14. 1 PM Sunny 66°
  15. 2 PM Sunny 66°
  16. 3 PM Sunny 67°
  17. 4 PM Sunny 67°
  18. 5 PM Sunny 66°
  19. 6 PM Mostly Clear 63°
  20. 7 PM Mostly Clear 60°
  21. 8 PM Mostly Clear 59°
  22. 9 PM Mostly Clear 58°
  23. 10 PM Mostly Clear 57°
  24. 11 PM Partly Cloudy 56°

10-day forecast

Details
  1. TonightOct 20 Partly Cloudy then Patchy Fog Partly Cloudy then Patchy Fog48°
  2. TodayOct 21 Patchy Fog then Sunny Patchy Fog then Sunny52°67°
  3. ThuOct 22 Mostly Sunny Mostly Sunny52°66°
  4. FriOct 23 Sunny Sunny51°66°
  5. SatOct 24 Mostly Sunny Mostly Sunny54°67°
  6. SunOct 25 Partly Sunny Partly Sunny53°69°
  7. MonOct 26 Partly Sunny Partly Sunny17%48°63°
  8. TueOct 27 Slight Chance Rain Showers then Partly Sunny Slight Chance Rain Showers then Partly Sunny17%56°
  9. WedOct 28 Partly cloudy Partly cloudy42°51°
  10. ThuOct 29 Partly cloudy Partly cloudy38°53°

Days after the National Weather Service's seven are MET Norway's outlook, a computer model with no forecaster's review.

Radar

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Weather news near Chicago

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Air quality

71
Moderate
Fine particles (PM2.5)

Acceptable. Unusually sensitive people should consider limiting prolonged outdoor exertion.

Forecast

  • WedModerate
  • ThuModerate
  • FriModerate

Chicago, IL reporting area · 52 min ago. Data from AirNow (EPA and its state, local and tribal partners); preliminary and subject to change.

Sun & moon

Sunrise 7:11 AM
Sunset 6:01 PM
Daylight 10 h 50 min (−2 min 40 s tomorrow)
Waxing Gibbous · 75% lit
Moonrise 3:45 PM Moonset 2:08 AM
Full moon Oct 26 New moon Nov 9

Almanac

Monthly
Normal high / low60° / 44°
Record high87° (1953)
Record low26° (1952)
Wettest2.28 in (1933)
Month to date2.54 in (normal 2.24 in)

Chicago Area, records since 1872. Normals 1991–2020. Data from NOAA's Regional Climate Centers (ACIS).

Nearby

Forecasters' discussion

From the National Weather Service office in LOT, issued 39 min ago

Key Messages

- Areas of fog, including potentially dense fog, may develop again late tonight into early Wednesday morning in and near the Chicago metro.

- An extended period of dry and above to much above average temperatures is expected through the upcoming weekend.

Discussion

Issued at 226 PM CDT Tue Oct 20 2026

An Omega block that is in place over the CONUS is expected to persist through the end of the week. The associated ridge axis will only ever so slowly crawl eastward over the coming days, which will maintain broad surface high pressure across the region. As a result, dry conditions with an abundance of sunshine will continue through the remainder of the week with high temperatures remaining above to well above normal for this time of year. Daily lake breezes will cause the coolest (low- mid 60s) high temperatures to be observed near Lake Michigan each day.

Much like last night/early this morning, optimal radiational cooling conditions will likely allow for fog to develop late tonight into tomorrow morning and possibly again in the coming nights/mornings. This will particularly be the case in and near the Chicago metro within the footprint of the marine-influenced air brought inland during the daytime, where the fog could become dense once again.

There is pretty good ensemble agreement at this point in time that the blocking pattern will break down by early next week. This will allow for a cold front to drop through the region sometime on Monday or Tuesday, resulting in a return to cooler and more seasonable temperatures for the middle of next week. The frontal passage may bring a chance for precipitation to the area early-mid next week, but support for this across the latest suite of ensemble guidance is not ubiquitous, and there are considerable temporal differences with when this next potential opportunity for precipitation may arrive as well.

Ogorek

Aviation

Issued at 1213 AM CDT Wed Oct 21 2026

Key Aviation Messages for the current TAF period:

- Fog, locally dense, is possible prior to sunrise, mainly at Chicago Terminals north of a KARR to KMDW line.

Winds are expected to be light and calm through the night. There is another chance for fog to develop this morning. It has already started to develop around and north of KENW where obs are already reporting 1/4SM. While fog development is not a certainty, if/when it does occur, it can be locally dense with vis potentially near zero. Similar to yesterday, vis improvement should be fairly quick after sunrise.

Light southwest winds are expected through much of the day before becoming more southeasterly toward sunset. Once the fog clears, VFR conditions are expected through the end of the TAF. There is another chance for patchy fog tomorrow morning, but the chances are not as great as recently.

DK

Lot Watches

IL...None. IN...None. LM...None.

Forecasts, observations and alerts in the United States come from the National Weather Service (NOAA); radar from NOAA's Multi-Radar Multi-Sensor system; satellite imagery from NASA's Global Imagery Browse Services (GIBS) and NOAA's GOES satellites; the map from the U.S. Geological Survey's National Map; air quality from AirNow (EPA and its partners); hurricane information from the National Hurricane Center; climate normals and records from NOAA's Regional Climate Centers (ACIS). Forecasts outside the United States and the UV index: MET Norway (CC BY 4.0); observations outside the U.S.: airport reports via NOAA's Aviation Weather Center. Place names: GeoNames (CC BY 4.0). Data are copied on a schedule and may lag the sources; for warnings that affect your safety, follow your local National Weather Service office and emergency officials. Weather news is drawn from the 4Search index and reflects what the press published. Terms of use.