Weather World
Mann Lake, IL Weather Forecast
Quick Weather Clicks
Settings
Sun & Moon
Mann Lake Weather Forecast
| TONIGHT | SUNDAY | SUNDAY NIGHT | MONDAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT | WEDNESDAY | THURSDAY | FRIDAY | SATURDAY |
 | |  |  |  | | | | | | |
| Patchy Fog | Patchy Fog | Partly Cloudy | Mostly Sunny | Mostly Clear | Sunny | Mostly Clear | Mostly Clear | Mostly Clear | Mostly Clear | Mostly Clear |
| Lo: 69°FLo: 21°C | Hi: 91°FHi: 33°C | Lo: 69°FLo: 21°C | Hi: 90°FHi: 32°C | Lo: 71°FLo: 22°C | Hi: 95°FHi: 35°C | Hi: 95°FHi: 35°C Lo: 71°FLo: 22°C | Hi: 95°FHi: 35°C Lo: 71°FLo: 22°C | Hi: 95°FHi: 35°C Lo: 71°FLo: 22°C | Hi: 89°FHi: 32°C Lo: 69°FLo: 21°C | Hi: 89°FHi: 32°C Lo: 69°FLo: 21°C |
POP = Probability of Precipitation.
Weather Outlook Updated: 1142 PM CDT Sat Sep 12 2026 
Mann Lake Radar Loop
Use the map search tool if you want to place a location marker on the radar map...
Mann Lake Weather Map
Mann Lake Quick Facts
Mann Lake Forecast Discussion
Meteorlogic Glosserator
Instant definitions for any meteorological term.
Instant definitions for any meteorological term.
Issued: 1257 AM CDT Sun Sep 13 2026
Key Messages
- Very warm conditions with small rain chances in parts of southeast Missouri and north of Interstate 64 are forecast today and Monday.
- A major late season heat wave is forecast Tuesday through Thursday. High temperatures will reach the middle to upper 90s with daily peak heat index values around 105 degrees or higher. A Heat Advisory will very likely be needed.
- Slightly cooler and less humid conditions arrive by the end of the week, along with low-end 15 to 25% chances of thunderstorm...