| NWS Forecast for: Vandalia IL Issued by: National Weather Service Saint Louis, MO Last Update: 5:36 pm CDT Aug 14, 2026 |  |
Tonight: Mostly clear, with a low around 75. Light southeast wind. Saturday: Mostly sunny, with a high near 94. Heat index values as high as 105. Southwest wind 3 to 6 mph. Saturday Night: Mostly clear, with a low around 74. Calm wind becoming southwest around 5 mph after midnight. Sunday: Mostly sunny, with a high near 93. Heat index values as high as 103. West wind 3 to 7 mph. Sunday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 70. Light north wind. Chance of precipitation is 50%. Monday: Mostly sunny, with a high near 85. Monday Night: Partly cloudy, with a low around 65. Tuesday: Sunny, with a high near 86. Tuesday Night: Mostly clear, with a low around 69. Wednesday: Mostly sunny, with a high near 90. Wednesday Night: A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 68. Thursday: A 20 percent chance of showers and thunderstorms. Partly sunny, with a high near 84. Thursday Night: A 20 percent chance of showers. Partly cloudy, with a low around 64. Friday: A 20 percent chance of showers. Mostly sunny, with a high near 82. | |
| Vandalia IL 38.96°N 89.11°W (Elev. 531 ft) | |
Visit your local NWS office at: https://www.weather.gov/lsx/ |
