Saturday's Severe Weather Risk
Update as of 6pm Saturday
The Storm Prediction Center has put the metro area back in a slight risk for severe weather, mainly this evening for the metro area points south.
There is a Severe Thunderstorm Watch until 1am for northern Illinois. We'll wait and see if any of this action will cross the state line. The biggest threats appear to be hail, damaging wind, and heavy rain. Stay tuned to CBS58 for updates throughout the night.
Update as of 9am Saturday
It appears the severe weather threat for later today has shifted farther south into Illinois. This is where the best dynamics look to be. We still run the risk for storms into this evening and tonight. You know the CBS58 Ready Weather Team will keep you updated both on air and online.
Please keep your eye to the sky on Saturday with chances for strong to severe storms by the early evening.
Key ingredients are forecast to come together Saturday evening across southeastern Wisconsin. Storms Friday night won't have an impact on the atmosphere for Saturday. Sun and clouds on Saturday should allow temperatures to warm into the low to middle 80s by the afternoon.
Sunshine will also help the instability increase. Explosive instability supports strong updrafts that are needed for severe weather. Cold air aloft from the jetstream will enhance that instability late in the day. The jetstream will also help produce wind shear, or the turning of winds with height. Strong wind shear supports rotating updrafts that are capable of producing large hail and isolated tornadoes.
The humidity will also increase on southerly winds on Saturday. Dewpoints in the upper 60s are forecast to stick around Saturday evening.
Timing: Showers and storms will ignite as a shortwave piece of energy moves overhead. We are expecting the storms to increase in coverage and intensify between 5 PM and 10 PM. The bulk of the storms will move through between 7 PM and 9 PM.
Threats: All modes of severe weather are expected along and south of I-94. Damaging winds between 50 mph and 70 mph, quarter size hail, and isolated tornadoes. The best chance for tornadoes will sit right along the border of Illinois and Wisconsin.
We will continue to watch the atmosphere closely throughout the day. Please download the CBS 58 Ready Weather App so you can get warnings right in the palm of your hand.