Severe threat continues south Monday afternoon - Could move south of northern Illinois late this afternoon

Tornado Watch issued for parts of Iowa, western Illinois and eastern Missouri until 7pm.

1:05am Update: Clearing in Missouri along with building instability has caused a few thunderstorms to develop northeast of Columbia, MO.  These were right along and south of the surface warm front which has stayed pretty much in place through the morning and early afternoon.  Thunderstorms also are forming closer to the surface low near the Iowa and Nebraska border north of Omaha.  There, stronger shear could promote a few tornadoes.  A weather watch will likely be issued for parts of Missouri, Iowa and west-central Illinois very soon.



Previous discussion:

After Sunday's devastating tornadoes that killed over 12 people, the south is gearing up once again for another active day.  Ongoing storms in parts of Tennessee, Kentucky and further south have already produced numerous severe thunderstorm warnings and even tornado warnings Monday morning.  The greatest threat for severe weather will remain over parts of Mississippi, Alabama and Tennessee later today, but the threat does extend further north into central and northern Illinois.  Most models indicate the highest instability will remain well south of the Stateline as thunderstorms from this morning have somewhat disrupted the flow of moisture from the Gulf.  However, clearing has begun to take place over Missouri and west-central Illinois late this morning and this area could become the focal point for thunderstorm redevelopment early this afternoon as surface low pressure strengthens and spins into Iowa.

A warm front sits from eastern Nebraska southeast through Iowa and into central Illinois.  North of the front clouds, east winds and morning rain has kept the atmosphere pretty stable and is expected to do so through the majority of the early afternoon.  South of the boundary, instability is slowly starting to build as upper level disturbances wrap around the surface low.  The disturbances will try to pull the warm front further north through the afternoon which could allow storms to creep back in after 4pm into northern Illinois.  While the chance of severe weather remains low, if the front were to slide close to I-88 the storm threat would increase with hail and damaging winds.  Of lesser concern would be a tornado threat, but enough wind shear near the surface warm front could cause a few isolated tornadoes to develop. 

We'll be watching closely the development of the front and just how much instability can build during the day.  The greatest concern for severe weather will stay south as another potentially dangerous day could unfold through the south.  Be sure to stay with the First Warn Weather Team for both local and national weather updates.