Arctic Air Arrives Wednesday With Snow Chance

The much-advertised cold blast and wintry weather potential is nearly here. On Wednesday, Old Man Winter pays us his first real visit of the season. While the precipitation will be meager, the cold air will not be in short supply. It’s not a long-term cold spell, but one that will be a weather whiplash given how warm our fall has been.

Our cool-down actually begun today behind a fast-moving cold front. Blustery north winds are bringing below-normal temperatures with wind chill values in the 30s. The real-deal Arctic air is just now invading the northern Rockies and Plains, but it won’t take long to reach us – by Wednesday afternoon, our temperatures will be dipping back to the freezing mark as wind chill values start to dip into the teens.

Wednesday will begin dry, but overcast for most of the area. We’ll see a small warm-up into midday before the reinforcing cold air arrives in the afternoon. As that occurs, a light wintry mix of drizzle, snow showers and freezing drizzle is possible. The latest computer model runs let the dry air win out with very little precipitation reaching the ground. 

However, it won’t take too much for the atmosphere to squeeze out a few snowflakes. There will be a small window for *light* accumulation as temperatures dip to freezing and before the moisture scours out. While a dusting is possible in the Tulsa area, it’s more likely that places near the Kansas or Missouri borders receive a very minor accumulation on grassy and elevated surfaces.  The map below shows that potential.

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A few snowflakes could even reach southeast Oklahoma in the evening. However, accumulation is unlikely. The main concern would be freezing drizzle, which could form instead of snow in some areas, creating a light glaze on bridges and overpasses. While, I wouldn’t change any travel plans just yet, be aware of this potential from Wednesday afternoon into the evening, especially in areas northeast of Tulsa.

The main impacts of this system will not be the precipitation potential, but the wind chills that come with this rush of Arctic air. Those feel-like readings will fall into the teens late Wednesday afternoon and flirt with the single digits by Thursday morning.  Thursday will be the coldest day as temperatures struggle to rise above freezing during the day with a wind chill holding in the teens to lower 20s all day. As the winds go calm on Thursday night, the coldest temperatures will break out. Widespread teens are expected Friday morning for lows. You can see the break-down of our cold air and expected minimum wind chill values below.

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Fortunately for those averse to cold weather, a warming trend will ensue as we head into the weekend. Another fast-moving storm system Saturday will spur strong south winds, removing that shallow, cold air in place and replacing it with more seasonable readings with highs near 50°. It’s not exactly “warm,” but a reprieve from the coldest air since last January.

The pattern into mid-December supports brief cold spells with only a few small opportunities for precipitation. The progressive pattern in the jet stream will allow lots of fast-moving systems to bring air mass changes, but not allow for enough time for moisture to return upon its passage for significant drought relief. That popularized “Polar Vortex” will be strengthening in Canada through mid-month, which will actually allow some of the coldest air to become more bottled up north as time goes on. While day-to-day variation is expected of course, we might not end up with prolonged periods of bitterly cold weather. That is, of course, not quite written in stone. As winter weather patterns take hold, there’s usually lots of volatility in forecasts beyond a week out.

For the latest on our wintry weather potential Wednesday and beyond, be sure to follow me on Twitter: @GroganontheGO and on my Facebook page for more updates!