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Weekend winter storm threat lingers in Northeast

We’ve discussed for a few days the threat for wintry weather this coming weekend – and while the evolution of the forecast has changed in the atmospheres mid and upper levels, the threat for wintry weather still does exist. With that being said, forecast model guidance continues to offer little help in regards to consistency and confidence as we move forward. A complicated situation is set to evolve across the Great Lakes and Northeast States this weekend.

An initial disturbance is still likely to drop southward into the Great Lakes, well from the northwest, associated with Pacific energy. It will undercut a piece of what is known as the “tropospheric polar vortex” – or the polar vortex that exists in our troposphere, where we experience most of our weather. The interactions between these two disturbances will be critical, and forecast model guidance is struggling with exactly how the two of them will behave.

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Despite strong signal, models differ on late week winter storm

Forecast models are a complicated thing: Meteorologists know, when major storms are looming, that they can often provide major hints and clues into how the atmosphere is going to evolve. Unfortunately, many readers or the general public don’t fully understand that models should be used for guidance, and not as fact. Quite possibly, the misunderstanding stems from meteorologists inability to communicate that.

Global models over the past few days have been strongly signaling the potential for a major East Coast storm system later this week. More specifically, many of them have been signaling the potential for a significant winter storm in our area. However, closer inspection of these global models reveals several large differences — and reasons why confidence is very low in any specific storm evolution as we move forward.

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Understanding the difference between potential and hype

I think I personally hit a bit of a breaking point today. Around 6:00am this morning, we received an inquiry regarding the potential winter weather events next week.  This is nothing terribly unusual — our email inbox is normally filled with these and we do our best to try and answer them and keep people informed. The title of the email read “Information Regarding Blizzard Feb 8” and the contents essentially asked us for our snowfall forecast for the upcoming “Blizzard” which the mailer was under the assumption was going to arrive next week. In the email was a model image, produced by Weatherbell Analytics, which showed the snowfall totals from a ECMWF Ensemble Control run at 200+ hours. It was then that I realized we had a big problem on our hands.

This is nobody’s fault. Not the mailer, nor the company which produced the map. It isn’t our fault, your fault, or any meteorologists. In fact — nobody is to blame. But it is a problem, because the image went viral on social media and many in the general public took it as fact. And so, as meteorologists, it is our job to source back this issue and try to figure out how to avoid it happening again. Similar things have occurred during storms in the past, as recently as a month ago, and the end result is never pretty.

This snowfall total map, which went viral yesterday, is a snowfall forecast from an ensemble member of the ECMWF model.

This snowfall total map, which went viral yesterday, is a snowfall forecast from an ensemble member of the ECMWF model.

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