Monday Evening Weather Update; November 9, 2020

A Winter Weather Advisory is in effect until 3 p.m. Tuesday for most of the KLKN-TV viewing area.

Winter Weather Advisory State

Winter Weather Advisories are in effect until Tuesday afternoon.

There are many things going on in the atmosphere Monday night/Tuesday morning.  To start, there is a pocket of “warm air” (above freezing) residing between 2,000ft and 8,000ft above the ground.  So any precipitation that falls in to that layer is going to melt and fall as rain.

Underneath the “warm layer” temperatures drop to at, or below, freezing.  This will allow the liquid to cool.  At the surface temperatures are expected to drop to the upper 20°s to lower 30°s by sunrise Tuesday.  As the liquid, falling as rain, reaches the ground surfaces that are at or below 32° will cause the water to freeze.

Ice accretion will likely happen for parts of the area, especially along I-80 by morning.  There is still some question as to how much freezing rain could fall.  Computer models are doing a horrendous job handling the cold air that rushed in to the area this afternoon.  Even this evening computer models are several degrees too warm.  That could mean that the computer models are underplaying the amount of ice accretion.

I do think there could be a corridor along and north of I-80 that could pick up 0.10″ to 0.20″ of ice by Tuesday morning.  If that happens, slick spots could develop on roads for the Tuesday morning commute.

By mid-morning the “warm layer” will be replaced by below freezing air.  Once that happens rain will change over to snow.  This will happen as an upper-level low pressure area passes overhead.  This could allow for slightly higher snow amounts from roughly a line from Broken Bow to Norfolk.  Somewhere in that band could end up with 5″ to 6″ of snow by late Tuesday afternoon.  Other areas, especially south of I-80, will have lesser amounts.

– Chief Meteorologist John Dissauer

Follow John on social media:
Twitter: @JohnDissauer

Categories: Channel 8 Eyewitness News Weather, Forecast