Thunderstorms a Good Possibility Later on Sunday Night

A  disturbance  caused a few showers with isolated lightning to develop across the Stateline late this afternoon. The activity has intensified  tonight. A low level jet with warm air advection along with disturbances moving in from the west will cause scattered showers tonight with thunderstorms developing eastward out of Iowa later on well after midnight. On Monday it will be partly cloudy and warmer in the north central part of Illinois as a warm front lifts northward. The Gulf of Mexico is pretty much blocked off so no heavy rainfall is anticipated. Winds will pick up as the pressure gradient tightens on Monday with the system low pressure system intensifying over the northern plains.  There could be some scattered showers and thunderstorms over far northwestern Illinois, and extreme southern Wisconsin on Labor Day, and across the entire area on Monday night as the strong low pressure system passes by to the north over far northern Wisconsin.  This will be a very intense the low pressure center, so, a tight pressure gradient will develop by Monday afternoon, and continue into Tuesday night.  Winds will gradually pick up during the day on Monday increasing to 15 to 25 miles an hour by afternoon with gusts above 30 mph.  It will continue very breezy overnight Monday night, and WIND ADVISORIES may be needed on Tuesday with winds 20 to 35 miles an hour gusting to near 45 miles an hour, and possibly higher.  High pressure from southern Canada will take control of Stateline weather on Wesnesday with mostly sunny skies and pleasant temperatures into the middle 70's by late afternoon.  On Thursday the high will shift off to the east allowing a warm front stretching from the Missouri valley southeast into the middle Mississippi valley to begin a slow northeastward movement.  There is a chance of some scattered showers and thunderstorms by late in the day on Thursday.  The system will be a slow mover, so, showers and thunderstorms will continue to be a threat across our region off and on through Saturday when a new cool front will sweep in from the west and clearing skies for Sunday.
By Meteorologist
Eric Nefstead