More Storms, Heat, and Flooding Possible

It’s Friday and we’ve got a lot to discuss regarding hazardous weather, advisories, and heat. To start off the day we’re already sitting in the lower 70s in Sterling at 6:30AM. More shower and thunderstorms are possible through much of the day mainly an on/off scenario. It’ll remain somewhat scattered and our chances for showers will decrease late this afternoon before more chances increase in our overnight hours.

Highs for today will be around 90 with a gentle south wind around 8MPH, again with periodic rain chances through today. Tonight we turn our attention to more active weather mainly after 11PM where we could see a line of strong thunderstorms move into our area from the northwest. These storms will be weakening as they continue through our area, but a strong or a severe thunderstorm is not out of the question. Below is a simulated graphic showing the line of thunderstorms entering our area after midnight.

Again, these will be on a weakening trend as they enter the Sauk Valley region, but our main hazards will be damaging winds, heavy rainfall, and small hail. A brief tornado can not be ruled out however. For this reason the SPC has and will likely keep our area under a slight risk for the threats listed.


Let us turn our attention to some of our active advisories and warnings.


A Flood Warning continues for the Rock River at Como. At 1:30 AM Friday, the stage was 10.6 feet and continues to rise. Minor flooding is already occurring and moderate flooding is forecast. It is predicted to rise to 11.6 feet Saturday morning and fall below flood stage Tuesday.

A Flood Advisory continues for the Rock River at Dixon. At 7:15PM Thursday the stage was 13.1 feet. Flood stage is 16.0 feet. It is predicted the river will rise to near 14.4 feet by Friday evening.

A Flash Flood watch continues for Lee county until Saturday morning. This is in part due to rounds of thunderstorms producing heavy rainfall with rates over one inch per hour. This will be likely late Friday through early morning Saturday.

A Heat Advisory has been extended for Whiteside County. A hot and humid air mass will remain over much of the area through Saturday. With the combination of the heat and humidity, the heat index values are expected to reach over 100 degrees Friday and Saturday. Temperatures in the upper 80s to low 90s are expected with heat index values up to 105 are possible. The heat advisory is expected to expire 8PM Saturday.