Wed. Jan 27th, 2021

Thursday Evening European Model Showed a Major Piedmont Snow…Today it’s gone!

Perhaps you have seen some other sites showing 8-12 inches of snow for the Piedmont already…This morning IT IS ALL RAIN and warm. Why?

Autumn is a season of transition not only for leaves but for the climate as well. This season, we have many different variables that under normal situations, would be easy for a model to calculate. A developing El Nino, Warmer than normal Pacific ocean currents, Siberian snow pack, Volcanic gas emissions, and Saharan dust storms. Yep, all of these influence the weather but to understand their impact, you have to think globally…our weather and climate models do exactly that. What you see here and on other weather pages are just snapshots (zoom-ins) of global models.

As they try to account for all these fluctuations sometimes they get really wonky…like we saw last evening.

Run to Run Model Variation
Run to Run Model Variation

Shown here is the difference between a crippling snow storm of 10+ inches of all snow to a steady cold rain. The Friday morning run pushed the approaching system further north and west. Before you let your guard down, THIS IS STILL 10 DAYS AWAY and models will change back and forth many times before locking in on a solution for us. This is also one model which is the only one that called for a southeast snow. The GFS and Canadian long-range models show us too warm for snow (or ice for that matter).

This is what Model error looks like…This is a “Spaghetti Plot” showing how reliable/accurate a model is through time. Notice when the animation starts, there are really tight lines. These represent the Northern and Southern Jet Streams. The farther in time it goes, the more the lines come apart. This is the model’s error. The yellow line is the average between all the line widths and last evening, the yellow line dipped into the Piedmont…this morning it has moved north. Without going into jargon, the point here is that beyond 5 days or so, climate models have less and less confidence. Models are a tool and not a forecast.

Bottom Line:

  • We still have the storms in the Pacific to deal with travelling on that Conveyor Belt nicknamed the “Pineapple Express”.
  • There is a lot of model uncertainty this far out. Storms will pass through the Piedmont but as you can see, things have to be just right for a White Christmas (or any other day) for us to get a good snow.
  • This is why we didn’t post the pretty pictures showing mountains of snow here last evening and only suggested to you that you keep the 17th through the 24th open and flexible with your plans.
  • We are still saying that this morning.
  • Stay tuned!

As always,

NC Weather Happens. Enjoy it!


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