A Major Winter Storm on the way

Nam 12Z 850mb heights, temp. and wind

Nam 12Z Precipitation (by midnight), 850mb temps. and MSLP




After dumping a record 3-6 inches in Las Vegas yesterday, a major winter storm with snow, ice and thunder is on the way. They say what happens in Las Vegas stays in Las Vegas, but unfortunately this storm is headed east bound and we are right in its track. Major forecast challenges continues as whether we will see a major snow storm or a major ice storm. Either way its going to be a mess especially for Friday's morning commute. It seems the axis of major snow/ice is along the I80 corridor. North of I80 will see more snow than frezing rain. South will see more freezing rain than snow. A Winter storm warning has been posted for the Chicagoland area. However, our neighbors just to our south in Kankakee are under an Ice storm warning. Upwards to 8-14 inches is expected along the Illinois/Wisconsin border. 5-9 for the city and west suburbs, 3-8 for the south suburbs (south of I80 3-6 inches), and 0-3 inches Kankakee and south where ice storm warnings are posted where they could see ice accumulations exceed 0.5 inches. The line of heavy snow and ice will be very sharp. The energy from this system will have enough for some convection meaning thunder snow/freezing rain. 1-2 inch per hour snow rates will fall overnight. This is all due the surfacebeing below 32 degree farenheit. This storm system will provide winds fron the south to warm the mid levels of the atmosphere to above freezing. This setup is for a classic freezing rain/ice storm event. The further south the more warm air advection. This is why there is an ice storm warnign for the counties south of us. Now, there is great concern that the towns along, just north and just south of I80 could see an overlapp of snow and ice. This means that there could be ice accumulations of 0.25-0.5 inches then snow accumulations of 3-8 inches on top of that.