| NWS Forecast for: Vandalia IL Issued by: National Weather Service Saint Louis, MO Last Update: 3:11 am CDT Aug 8, 2026 | |
| Today: Sunny, with a high near 88. Light west wind. Tonight: Mostly clear, with a low around 68. Calm wind. Sunday: Sunny, with a high near 90. Heat index values as high as 101. Light southeast wind becoming south 5 to 10 mph in the morning. Sunday Night: Mostly clear, with a low around 73. South wind 7 to 9 mph. Monday: Sunny, with a high near 91. Southwest wind 6 to 9 mph. Monday Night: Mostly clear, with a low around 75. Tuesday: Mostly sunny, with a high near 91. Tuesday Night: A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 73. Wednesday: A chance of showers, with thunderstorms also possible after 1pm. Mostly sunny, with a high near 88. Chance of precipitation is 30%. Wednesday Night: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Partly cloudy, with a low around 70. Chance of precipitation is 60%. Thursday: A 50 percent chance of showers and thunderstorms. Partly sunny, with a high near 84. Thursday Night: A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 67. Friday: A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 81. | |
| Vandalia IL 38.96°N 89.11°W (Elev. 531 ft) | |
Visit your local NWS office at: https://www.weather.gov/lsx/ |