It wouldn't be spring in Mid-Missouri without a few curveballs, and that's exactly what we're dealing with this week after starting out with temperatures near 70 degrees on Monday with measurable snow less than 24 hours later.
An unseasonably cool two weeks can be blamed on the upper air pattern, with cold air masses on opposite coasts trapping us in a stagnant pattern last week, and cold air from Canada diving south this week. A strong cold front dropped our temperatures more than 30 degrees between Monday and Tuesday. Just enough energy associated with this front allowed precipitation to set up across the Midwest and Plains Tuesday, bringing measurable snow on the order of a dusting to 2" to Mid-Missouri.
A new latest measurable snowfall record of 1.3" was set at Columbia Regional Airport Tuesday afternoon, replacing the old record of 0.8" set on April 20, 1904. The latest report of snow flurries in Columbia was set on May 13, 1953.
Along with the rare wintry weather, record low temperatures could also be broken or come close Tuesday and Wednesday nights as temperatures dip into the upper 20s to around 30. The record in Columbia is 29 degrees both nights. A Freeze Warning goes into effect Tuesday night and expires at 9:00 AM Wednesday.
Frost forms when warm air rises as skies begin to clear and the temperature drops at night time, allowing air just above the surface to cool. This cooling forces moisture near the ground to sink onto the grass (or plants) and freeze on contact, creating frost.
Plants are highly susceptible to damage when temperatures get this cold. Hopefully you had the chance to cover vegetables or flowers in your garden and bring in potted plants from your deck or porch with a light to moderate freeze expected tonight. Unfortunately, widespread damage can be expected when temperatures get under 28-29 degrees. A severe freeze (25-28 degrees) can kill the most hardy perennials and trees.
Another cold night is expected on Wednesday, with lows falling into the upper 20s to around 30 once again Thursday morning. This is likely our last freeze for the season as temperatures will warm back in into the 40s and 50s at night from Thursday on into next week.