Stalled System Tonight...Sunday Afternoon Looks Good

The cold front that generated severe weather on Friday afternoon, and evening has pretty much stalled out this evening.  It stretches from a vertically stacked large upper low over Lake Winnipeg in Manitoba Provience, Canada across Lake Superior, western lower Michigan, southwest to near St. Louis, to southwest Arkansas, to a surface low over Texarkana, and then southwest to the lower Rio Grande Valley.  The front pretty much parallels the upper jet stream.  A mid level disturbance over Texas will get caught up in the northeast flow overnight, and enhance the surface low as it moves across Arkansas and Missouri through east central Illinois by morning.  A band of precipitation has developed in association with this system from Oklahoma, across Missouri, and western Illinois into the north central Illinois area.  Within that band, an area of thunderstorms has developed from extreme northeastern Oklahoma though Missouri to just south west of Quincy, Illinois.  As the entire system moves northeast tonight, enhanced by a 50 knot low level jet, precipitation will overspread the entire Stateline region by late evening.  Conditions appear to be too stable in this area to be able to  to support any thunderstorm activity.  It looks as if any thunderstorms that do occur, will be well off to our southeast.  Rain will be likely from late evening until 4 or 5 am in the morning.  Right now it appears as if it will be mostly light rain, but totals by morning may be a quarter of an inch in some areas.  The rain will scatter on out during the early daylight hours on Sunday, and should be all finished by late morning leaving the day partly sunny with warm afternoon temperatures reaching the low 70's once again.  The large upper low over Manitoba will move slowly into western Ontario on Sunday, and spin a trough of low pressure southeast across the northern plains reaching the Stateline overnight on Sunday night.  Although, this does not appear to be a moisture rich environment, it does look to be quite unstable with some very cold air aloft, so, again showers will probably develop overnight on Sunday with even the possibliity of some thunderstorms over southern Wisconsin.  Any scattered light showers remaining on Monday will not amount to much.  A warm front will push back northward  across the area on Tuesday taking temps back into the low 70's again. No precipitation is expected because of limited moisture availability.  Another front will move through the area on Wednesday with very little affect on the weather.  That front will stall out near the Ohio River Valley on Thursday as the upper flow becomes more westerly, and disturbances moving from west to east across the plains to the north of the front cause showers and thunderstorms to break out in our area from Thursday into Friday.  A push of colder air from Canada will end the precipitation on Friday night. In fact, it may be cold enough Friday night for some patchy frost over parts of southern Wisconsin, with low temperatures below 40 degrees.  Next weekend looks like it will be dry at this time.
By Meteorologist
Eric Nefstead