Subtle wave in jet stream may bring a shower/storm Saturday night

Low pressure developing over the Plains Friday evening will pull a cool front back north as a warm front Saturday morning.  Following the warm front temperatures will climb into the upper 80's and low 90's Saturday afternoon.  Dew point temperatures should still remain in the 50's, keeping humidity values still tolerable.  The heat index through the weekend isn't expected to rise much past the upper 90's.

With the jet stream passing to the north and settling into Wisconsin this weekend most of the storm activity will remain to the north.  However, a very subtle and weak upper level wave will move through the jet stream late Saturday night and Sunday morning.  Thunderstorms are possible over the northern Plains, Minnesota and Wisconsin Saturday afternoon and evening.  With this subtle wave moving through it's very well possible that a few storms could slide through southern Wisconsin and far northern Illinois into Sunday morning.  The atmosphere doesn't look overly support for thunderstorms to maintain themselves over the Stateline during this time, but there is still a chance for storms.

Ridge then pushes back north Sunday with temperatures staying in the low 90's for Sunday, Monday and Tuesday of next week.