Traditionally, we stick to a 7-day forecast on air. Beyond that, forecast confidence decreases. We can tell general trends, but nailing down specifics is next-to-impossible. At the same time, we understand the thirst for knowledge and information. In trying to balance responsible science with people-pleasing, we've come up with this blog post about the Thanksgiving week forecast.
The folks at the Climate Prediction Center regularly issue 6-10 day and 8-14 day temperature and precipitation outlooks. This is the 8-14 day temperature outlook, which shows a low-medium level of confidence in cooler-than-average weather here.
There are two reasons for this lack of confidence. 1) Inconsistent forecast data and 2) A changeable weather pattern.
Two things we can use to diagnose what might come the week of Thanksgiving are 1) The current snow cover in Siberia and 2) Something called the North Atlantic Oscillation.
Siberian Snow Cover
Currently, there's a lot of snow cover in Siberia. It may seem odd that we're looking at this, but there's a reason.
White-colored objects, like snow (don't taste the yellow kind), reflect light more than say asphalt. That reflection of the sun's light warms up a higher section of the atmosphere (known as the stratosphere).
That warming effect will loosen the winds up north, essentially loosening the grip on colder air. Because of that, we are fairly confident in a blast of cold air somewhere in the 11/19-11/21 time frame.
How long does that cold air stick around? That's where things become trickier.
North Atlantic Oscillation
The North Atlantic Oscillation refers to the pressure difference between the Icelandic Low and Azores High. If the pressure difference is smaller, as is indicated in most medium-to-long range forecast models, then the winds in the North Atlantic would loosen. Once again, loosening winds would allow for more cold snaps in the eastern half of the US during the second half of November.
Based off of this information, we are fairly confident that it will get cold in the 11/19-11/21 time frame. Beyond that, the inconsistency in our forecast data has us still scratching our heads on Thanksgiving itself.
For those wondering about snow, it's too soon to tell. With the cold snap in the 11/19-11/21 time frame, the winds would have to come perfectly from the NW off of Lake Michigan for there to be any mountain snow. If the winds take more of a turn from the west, that chance goes down.
Keep checking back for updates on air, on our mobile app, on our website, and on our social media pages. We understand the desire for knowledge during your holiday plans, but we also have to tread carefully when trying to forecast long-term.
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