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GRAND RAPIDS, Mich. (WOOD) — A flash freeze is in the forecast for Thursday night. It sounds ominous, but what does it mean?
The only other time we use the word ‘flash’ in meteorology is when we are talking about flooding. It just means we expect something to happen fast. For example, the only time a flash flood warning is issued is when we expect flooding to happen rapidly, over the course of minutes rather than days.
A flash freeze has much the same connotation. We expect temperatures to cool faster than usual Thursday night thanks to a cold front that will swing in.
We are expecting to drop from the mid-40s to freezing in about a four-hour window, with temperatures continuing to steadily tank as the night wears on, allowing any ice that refreezes to harden.
The reason it is important to talk about now is because of all the ice on our trees. Any ice that doesn’t fall off in the afternoon’s quick warm-up will rapidly freeze back onto limbs and powerlines. The wind will pick up, too.
If we are lucky, the wind will kick off a lot of the ice before it solidifies back onto trees and lines. If not, the wind will work to knock down heavy trees and lines, exacerbating the power outage situation.
Ice is incredibly heavy. Just half an inch of ice can add up to 500 pounds on a powerline — not just the poll or a tree, but an actual, single line.