The trend is your friend - that is the mantra for meteorologists when watching for potential storms and pattern shifts. After a very mild December for much of the country, the trend is a big pattern shift heading into the second week of January.
The area of focus for this blog post will be January 8-11.
The European (left) and American (GEFS, right) ensembles both show a strong trough in the jet stream that features a winter storm in the central US with the potential of heavy snow. Even about eight days out, there aren’t major differences in the upper-level patterns which show higher-than-normal confidence in this winter storm threat.
Before getting too much deeper into the models, I did want to show the current thinking of the Climate Prediction Center regarding the snow threat. This goes to show the strong signal in the models that they are putting out a Moderate Risk for Heavy Snow.
While the upper-level pattern is coming into agreement, what happens at the surface is still rather uncertain. Above you can see the range of solutions with a center of the storm as far north as Clinton, Iowa to as far south as Birmingham, Alabama.
The main takeaway here is that there is rather high confidence in a storm, however location and impacts are still being worked out which is common a week out.
Based on the European Ensemble, the probability of at least 3” of snow is rather high stretching from western Kansas through the Great Lakes - therefore this is the area we are closely watching for impactful snow.
The actual width of heavy snow will be more narrow than indicated above, but eight days out the range in possibilities remains high. Eastern Iowa, northern Illinois and southern Wisconsin are most interesting at this stage.
Another thing worth watching into the extended period is the likelihood of winter temperatures finally making an appearance. Analogs show with pretty high confidence below-normal temperatures for much of the US following the storm early next week in the middle of the month.
That’s a cold signal!
That’s it for now, more to come as the forecast becomes more clear.
-Meteorologist Nick Stewart
