Scattered storms possible today, hit-or-miss this weekend

What is an M.C.V?:

Thunderstorm chances are back in the forecast today, and it all ties back to something we call an M.C.V, or Mesoscale Convective Vortex. This is essentially a leftover spin in the atmosphere that develops within a cluster of showers and storms. Even after the main storms weaken or move out, this compact area of low pressure can linger and act like a spark for new storm development. The added spin from an M.C.V could also enhance the threat for weak tornadoes. 

Today's Severe Threat:

As for the severe threat today, areas south of highway 20 in northern Illinois are under a level 2 of 5 - slight risk for scattered strong to severe storms. It's not a slam dunk setup, though. Earlier rain and storms have worked the atmosphere a bit, which could limit how much additional thunderstorms is able to develop later on. That said, if storms could tap back into some of the available storm fuel, a few could become strong with gusty winds and heavy downpours. And while the overall threat remains on the lower end, it's still worth keeping an eye on, especially in the slight risk area where the spin will be enhanced due to the incoming M.C.V. 

For those who miss out on any of the scattered storms this afternoon and evening, it'll be a different story. Conditions will stay dry, partly cloudy, but noticeable more humid, with that muggy feel really settling in. Even without the rain, it'll be a summer-like finish to the day with afternoon highs in the low 80s and dew point temperatures in the upper 60s.  

  

Weekend Outlook:

Thunderstorm chances on Saturday look to be more isolated and pulse-like, meaning we're not expecting much in the way of severe weather. Instead, a few individual storms could quickly pop up during the heat of the afternoon, briefly intensify, and then fade just as fast. So hit-or miss. Some will see rain and others will not. Most areas however will stay dry with highs climbing into the mid 80s. As we head into Sunday, most of the daylight hours should stay dry with a mix of clouds and sunshine. Rain chances hold off until later, with the next opportunity for showers and thunderstorms arriving during the overnight hours Sunday night.