The frequency of snow occurring after the start of meteorological spring in Missouri
Sunday, March 1st, is the beginning of meteorological spring. Of course, Central Missouri gets to start this new season with winter weather, even after the spring-like conditions that have been in the area today and will be in place throughout Saturday. It may seem like the start of a new season should mean that the weather from a different season should come to an end, but for Missouri, that is rarely the case.
For far southern Missouri, the average last snow occurs anywhere from February 1st to March 1st. For almost all of the rest of Missouri, March 1st to March 20th is when the average last snowfall occurs, but this does not mean that snow never occurs past those dates.
Since March in Missouri is still in the transition period from winter to spring, measurable snow totals for the entire month average to around 2.3" for St. Louis, 2.0" for Springfield, and 1.5" for Columbia, all based on data collected from 1991-2020. This all typically falls on a couple of days during the month, meaning that snow after the start of meteorological spring is common in most parts of Missouri.
As for April, the occurrence of snow is even less frequent, but not impossible. Out of all the recorded data from 100+ years, there is only measurable snow in 25-30% of those years. This most frequently occurs near the Missouri-Iowa border, and this is because of the cooler climates and stronger winter influences persisting in those areas. This is the same reason why the last freezes and frosts in Missouri typically come later in the spring for far northern Missouri.
One of the more recent notable winter events that occurred in the late spring was April 1st, 2018, where a band of snow brought around 5 or more inches of snow for areas north of I-70, more specifically near Macon and Paris, Missouri. Surprisingly, this was the largest event of the "winter" season, as the weather throughout the majority of the true winter season had been a bit more settled. Areas near I-70, like Columbia and Jefferson City, still received almost an inch of snowfall, which also had sleet mixed in. This was the first Easter Sunday snow since 1961 in Columbia, and on the following day, a record low of 23 degrees from 1992 was tied. This goes to show that although it is rare to get winter weather deep into the spring season, it is not unheard of for the state of Missouri.
Although fewer widespread impacts are expected, there will still be wintry weather to start meteorological spring on Sunday. Areas near Macon and Paris, Missouri, can expect mostly snow throughout this event, with totals ranging from trace amounts to around 2 inches. Areas along I-70, like Columbia and Jefferson City, will get a mix of rain, sleet, and eventually snow Sunday evening into the overnight hours. Although accumulations aren't as high, there still could be travel impacts that linger into the start of Monday morning before temperatures eventually warm above freezing.
