A new Tornado Watch has been issued for all of central Illinois and west-central Indiana through 3am Tuesday morning. Severe storms were quick to develop over central Illinois, near a warm front, Monday evening. Flash Flood Warnings and numerous severe thunderstorm warnings have also been issued.
The warm front has stayed south of the area all afternoon leaving our air mass overhead a little more stable. There’s been quite a bit of wind shear (changing wind speed/direction) above the surface, but the instability was lacking. There has, however, been quite a bit of moisture in the atmosphere and that allowed some of the rain showers to be efficient rain producers.
Light showers will continue through Midnight but locally dense fog will likely become more of a concern by Tuesday morning. Visibility has already fallen down to under a half mile in some locations.