Weather World
McCormick, IL Weather Forecast
Quick Weather Clicks
Settings
Sun & Moon
McCormick Weather Forecast
| TONIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | SUNDAY NIGHT | LABOR DAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT | WEDNESDAY | WEDNESDAY NIGHT | THURSDAY |
 |  |  | | | | | | | | | |
| Clear | Sunny | Partly Cloudy | Sunny | Mostly Clear | Clear | Clear | Sunny | Clear | Clear | Mostly Clear | Mostly Clear |
| Lo: 75°FLo: 24°C | Hi: 100°FHi: 38°C | Lo: 71°FLo: 22°C | Hi: 91°FHi: 33°C | Lo: 65°FLo: 18°C | Hi: 90°FHi: 32°C Lo: 69°FLo: 21°C | Hi: 90°FHi: 32°C Lo: 69°FLo: 21°C | Hi: 95°FHi: 35°C | Hi: 99°FHi: 37°C Lo: 71°FLo: 22°C | Hi: 99°FHi: 37°C Lo: 71°FLo: 22°C | Hi: 95°FHi: 35°C Lo: 75°FLo: 24°C | Hi: 95°FHi: 35°C Lo: 75°FLo: 24°C |
POP = Probability of Precipitation.
Weather Outlook Updated: 1127 PM CDT Fri Sep 04 2026 
McCormick Radar Loop
Use the map search tool if you want to place a location marker on the radar map...
McCormick Weather Map
McCormick Quick Facts
McCormick Forecast Discussion
Meteorlogic Glosserator
Instant definitions for any meteorological term.
Instant definitions for any meteorological term.
Issued: 1141 PM CDT Fri Sep 4 2026
Key Messages
- An Extreme Heat Warning remains in effect through tomorrow for a prolonged dangerous heatwave with daily heat index values ranging from 103-110 degrees. There is a 30-80% chance of triple digit heat index values continuing into Sunday over southeast Missouri, the Purchase Area of Kentucky, and adjacent portions of southern Illinois.
- Near record high temperatures in the upper 90s to around 100 degrees and near record warm overnight low temperatures in the mid to upper 70s are expected...