Frost expected tonight even while forecast above freezing

Mid-Missouri felt a widespread freeze Wednesday morning and while temperatures will be a few degrees warmer tonight, it will still be cold enough for frost. Even before a hard freeze, frost can become a hazard for plants in marginally warmer conditions.

When sensors record temperatures in the mid-30s, this reading is often taken several feet above the ground. The air temperature can differ impressively in just these few feet, and air closer to the ground can reach freezing long before temperature gauges catch it. This temperature gradient is the most exaggerated on nights that produce frost.

For the best chance of frost, little to no cloud cover is optimal. Clouds reflect heat by the greenhouse effect while clear skies allow temperatures to cool efficiently. Light winds are also a necessity, as a high breeze wicks away cold air as it tries to settle near the ground.

Frost is not atypical this time of year, Mid-Missouri can usually expect the first frost of the season by mid to late October. The forecast for the rest of the month is trending warmer than average which will likely keep more frosty nights at bay.