ST. LOUIS, Mo. – Light snow is expected to fall all over the area starting very late tonight and going on until just before dawn on Tuesday. This snow will be light, but the timing of the most robust snow, in the hours between midnight and the morning rush, will lead to some challenges for the Tuesday morning commute.
The precipitation may briefly be mixed with rain at the onset, but will quickly transition to all snow. Ground temperatures have cooled quite a bit over the past few days and this, along with the overnight timing, will make it easier for some of the snow to stick to roads. This is especially relevant for elevated road surfaces.
St. Louis snow forecast timeline:
The snow will begin southwest of St. Louis after 8:00 p.m. It should arrive in St. Louis around midnight. It will quickly spread to the northeast from there. This is a quick hit of snow, with accumulations only falling for a few hours in any one location.
Snowfall totals will be heaviest to the northwest of St. Louis City from central into northeast Missouri. That is where 2 to 4 inches of accumulation is possible.
- 8:00 p.m. to 10:00 p.m. – Snow near Rolla, Missouri moves northeast
- 10:00 p.m. to Midnight – Snow begins to fall in the St. Louis area
- 12:00 a.m. to 2:00 a.m. – The snow moves to south central Illinois
How much snow will Missouri and Illinois get?
Most of the rest of the region is in line for 1-2 inches. Amounts will taper to less than 1 inch as you move into southeast Missouri and southern Illinois.
Will schools call off classes Tuesday? That is not yet clear. If they do, the closing will appear on this list.
Temperatures will rebound above freezing during the morning Tuesday, so roads should improve rapidly with the onset of daytime heating.