ST. LOUIS, MO - Warmer temperatures are finally in the forecast for the St. Louis region, but so is a storm system that looks to bring a mix of precipitation to the area on Sunday. After sunny and cold Saturday, clouds return ahead of a warm front Saturday night. Temperatures dip Saturday evening before starting to rise again overnight. Light snow develops early Sunday then mixes with freezing rain and sleet by late Sunday morning as temperatures above the surface climb above freezing. The icy mix gradually changes to a cold rain Sunday afternoon and evening as temperatures climb before ending as wet snow and sleet late Sunday night or very early Monday morning.
Some ice accumulation is possible so travel could be dangerous. Ground temperatures are well below freezing so even after the air temperature warms to above freezing icing will be possible.
Clouds return Saturday night ahead of a warm front. Temps dip Saturday evening before rising again overnight. Snow develops early Sunday then mixes with freezing rain & sleet by late Sunday morning. Ice will accumulate on untreated surfaces. Updates all weekend long. #stlwx pic.twitter.com/mCUnHxhhPU
— Angela Hutti (@AngWxGrl) January 5, 2018
— NWS St. Louis (@NWSStLouis) January 5, 2018
Ever wondered how a wintry mix forms? What matters most is how the temperature changes between the clouds and the ground. Different combinations result in snow, sleet, freezing rain, or rain at the surface. #stlwx #midmowx #mowx #ilwx pic.twitter.com/N0jcXaoLqk
— NWS St. Louis (@NWSStLouis) January 4, 2018