Two rounds of wintry precipitation possible Saturday night through Monday morning
ST. LOUIS – Two rounds of wintry precipitation are possible from Saturday night through Monday morning. A Winter Weather Advisory will be in effect from 12 a.m. to 12 p.m. Sunday for the entire region.
The first of these rounds is expected to begin overnight Saturday into early Sunday morning. Precipitation will be light to moderate, but road conditions could deteriorate very quickly after precipitation begins.
There are some questions as to precipitation type, but snow and a wintry mix will spread northeast into the region through the early morning hours. North of St. Louis will see mainly snow. To the south of St. Louis, there will be more of a sleet/freezing rain mix that could result in a light glaze up to 1/10th of an inch of ice. While snow and ice amounts should stay light, temperatures will be well below freezing so it won’t take much to make travel hazardous through the morning hours.
Snow amounts for St. Louis and points north will be less than 1″ and a light glaze of ice will be possible from St. Louis and points south.
As temperatures warm on Sunday, the snow and wintry mix should change over to rain. Highs on Sunday should climb to the mid 30°s.
There is more uncertainty with a potential second round of wintry precipitation for Sunday night into Monday morning. The question will be how far north rain will move into the region and the corresponding temperatures. A wintry mix of sleet, freezing rain, and rain will be possible Sunday night into Monday morning, especially along and north of I-70. To the south, the precipitation should stay mostly, if not completely, liquid. This means the Monday morning commute could be slick in some areas. The good news is that temperatures should climb above freezing fairly early on Monday morning, so any precipitation should change to rain rather quickly.
Rain chances will then continue through Monday and Monday night, but temperatures should stay above freezing for this time period.