Weather Alert Day: Dangerous cold to start Monday

UPDATE:

Cold air has filled the region, dropping wind chills into the near-to-below zero range. Winds slowly relax through the day, allowing for less extreme wind chills by the afternoon.

The ABC 17 Stormtrack Weather Team has issued a Weather Alert Day ahead of the potential for a few strong storms, accumulating snow, strong non-thunderstorm winds, and wind chills near or just below zero between Sunday and Monday.

Severe thunderstorms have ramped up along the cold front approaching St. Louis, with the severe threat ending for Mid-Missouri. Attention will now turn to snow showers, rapid temperature drop, and strong non-thunderstorm gusts to 50 mph tonight into Monday morning.

SETUP & TIMING:

Temperatures have already begun to plummet to the 50s where the cold front has moved through, and storms have fired up along the cold front. Strong winds will pick up behind the front in addition to snow showers wrapping around low pressure. Snow chances look to linger through the first half of the overnight before clearing Monday morning, when cold and wind will be the big story.

IMPACTS:

Impact potential is becoming clearer as the timing of the cold front is becoming more consistent, as well as the moisture behind the front. This gives us a better idea of the type of severe threat that will be present in Missouri ahead of the front, as well as when the transition to snow will occur. There also remains high confidence that we stand to be quite windy and cold Sunday night into Monday morning.

SNOW:

The snow chance is questionable as well. We are uncertain exactly how much moisture makes it into the wrap-around portion of this low. The northwest side of this will surge in cold air at the low levels and try to take advantage of what moisture is available, creating snow showers overnight. The potency of this snow is greatest in the northeast, nearest this low that passes by. We are also quite warm leading into the event. The soils are warm and still wet in spots, which may make ground temperatures slow to cool. It's possible that warm ground temperatures could contribute to more of a slushy accumulation at first. Still, winds will be dropping temperatures into the 30s and 20s while the snow falls, and eventually into the teens by Monday morning. This will eventually freeze anything that is initially slushy, but early warmth could greatly cut down on accumulations.

Snow accumulations currently look limited, with chances highest across the region for less than 2 inches of snow. It's entirely possible we only record trace to 1 inch amounts in the northeast. A less likely scenario does exist where we end up with such little snow that accumulation is avoided, but it still looks likely for some at the moment.

COLD & WIND:

Due to the confidence in high winds throughout this entire period, a wind advisory has been issued for the entirety of Central Missouri until Monday afternoon.

The aforementioned cold will be less uncertain as winds rush in Sunday night. Wind gusts as high as 40-50 mph at times, with winds sustained around 20-30 mph will drop temperatures well into the teens by Monday morning.

Wind chills could drop a few degrees below zero by Monday and continue to stay bitterly cold throughout the day.