PITTSBURGH (KDKA) — If you’re looking for a white Christmas, the large-scale weather pattern may not end up being in Pittsburgh’s favor this year. 

The early part of this week featured a brief thaw after a short-lived cold snap last week. Colder air will make a return to the Ohio Valley and Great Lakes region this upcoming weekend. A large trough or dip in the jet stream will result in a surge of Arctic air to push south toward our region. 

It will not be extremely or dangerously cold as the air mass will modify or lose its original potency as it loses latitude with southward progression. Still we expect high temperatures to be 5 to 15 degrees below average on Saturday, Sunday and Monday next week.

Warm-up arrives for Christmas

Just in time for Christmas Eve and Christmas Day, the large-scale weather pattern is projected to shift across the entire country. The general consensus among model guidance is for the deep trough of cold air to lift out of the Great Lakes, Ohio Valley and Northeast and be replaced with a more zonal or west to east flow from the Plains and Pacific West Coast. 

This will result in a substantial and likely long-lasting warming trend that will carry us from Christmas onwards. The Climate Prediction Center has shaded virtually all of the Contiguous U.S. in a moderate to high probability of warmer than normal temperatures in their Dec. 24 to Dec. 30 outlook. 

While we are likely going to be shifting into a pattern with above average temperatures around Christmas, that doesn’t necessarily mean it will be sunny either. Surges of warm air often come with moisture in this part of the world, so we could be looking at more clouds and possibly some rain chances around Christmas. Perhaps if you’re fortunate enough to have elevation or latitude working in your favor, you may be able to squeeze out some snow in Western Pennsylvania, but as of now, things aren’t looking too great.

What are the odds of a white Christmas in Pittsburgh? 

Statistically, the probability of Pittsburgh seeing a white Christmas is around 25%, so the odds are often in favor of no white Christmas— especially from Pittsburgh south and west. Odds increase farther north toward Lake Erie where lake-enhanced snows help raise this potential and in the Laurel Highlands which usually are the first to receive wintry precipitation because of their higher elevation and more frequent time spent above the freezing level.

Here’s how the odds are shaping up for this year.