Arctic Air To Move Into Oklahoma This Weekend

Arctic air will come in STRONG Saturday night and Sunday morning with many locales falling below 32° by sunrise. The plunge won't stop there, as Arctic air will continue to seep south across the remainder of the state. By sunset on Sunday, temperatures in the 20s will be commonplace across the entire state - that has me concerned.

Freezing rain occurring in surface temperatures of 28° or less means ice will readily accrete (build) on all exposed surfaces: roads, power lines and trees. While precipitation rates/amounts don't look impressive, a steady freezing drizzle for several hours could be all it takes for 0.1" to 0.2" of an inch of ice to accrete on exposed surfaces here in OKC.

Wind strength will also be a big contributing factor to ice accumulation impacts. Northeast winds will average 15-25 mph throughout Sunday. The ice accumulations combined with the wind would be enough to result in localized utility interruptions, as well as slick and hazardous traveling conditions.

Then there's the snow, which still remains one of the more uncertain aspects of this winter weather event. There's been some indication within a select model (GFS) that the system is slowing down. This could result in the storm's impacts being felt overnight Sunday into Monday morning, as well as accumulating snow along and north of I-40. Right now, I'm more concerned with freezing rain and sleet than snow.

Thermodynamic profiles also suggest some convective elements will come together to support thunderstorms in southeastern OK. If the instability builds farther north into central parts of the state, we may very well see thunder sleet/freezing rain in OKC.

Very tricky forecast, and the storm is still out over the Pacific away from our land-based observation network. Take it all with a grain of salt for now.