A killing frost or freeze is likely tonight and tomorrow morning for many in the mid-Mississippi Valley, the lower Ohio River Valley, and portions of the northern Mid Atlantic. Because of this threat, the National Weather Service has issued multiple frost and freeze advisories.
High pressure moving in behind a cold front is responsible for the conditions making it ripe for what’ll be the first frost or freeze of the autumn season for many. The high will allow for drier and colder air filtering into the area, with clearing clouds allowing for radiational cooling. Temperatures will likely fall to or below freezing north and west of the Fall Line in the Mid Atlantic and elsewhere across the central Appalachians into the Mid-Mississippi River Valley. Here, a large area of Freeze Warnings have been issued.
Over the Urban Corridor around I-95 in the Mid Atlantic, the National Weather Service has issued a Frost Advisory. According to the National Weather Service, temperatures will likely be highly variable in this area based on proximity to the urban centers. Upper 30s can be expected in the highly urbanized centers, with temperatures decreasing to the low to mid 30s, just outside of the urban centers. Pavement on parking lots and driveways, highways, and large brick and steel buildings will hold onto the heat longer, preventing a deep, solid freeze from occurring in many of the highly urbanized centers for now.
Frost and freeze conditions will kill crops, other sensitive vegetation and could possibly damage unprotected outdoor plumbing. The National Weather Service is encouraging people to take steps now to protect tender plants from the cold. To prevent freezing and possible bursting of outdoor water pipes they should be wrapped, drained, or allowed to drip slowly. Those that have in-ground sprinkler systems should drain them and cover above-ground pipes to protect them from freezing. Those with sensitive pets or animals should also take steps to protect them from possible freezing conditions.