Concerning next week’s arctic cold wave:
I will follow the model which lines up best with the past three days’ worth of output (ECMWF), and ignore the GFS model which is delaying the front until Monday afternoon. However, all outputs agree on coldest of the season weather, at least for daytime highs, along with low wind chills next week.
Several surges of colder air should keep all of next week colder than average for early to mid January. I’m keeping a slight chance of snow in for Monday-Tuesday based mainly on the condensation potential of the very cold low-level air, but amounts should be light as the main upper support from a mid-level low tracks to our north.
One model (FNMOC) does show the mid-level low passing overhead Monday, but this output does not match the others. Also, this model appears to have initialized the low too far to the south Wednesday. The other models including the latest GFS run shift it further north, which would keep accumulating snow to our north as well. This is a good example of how blindly following a model without fact-checking and tracking can cause forecast problems (discussion continues below map).
Some accumulating snow is certainly possible, but I’ll keep significant snowfall at a low probability unless the other computer solutions begin to lean toward the FNMOC’s mid-level trough position.
I had a blog question about cold air even further into the future. Gee, yall…that’s getting out there!
The GFS indicates the Polar Vortex (PV) coming very far to the south the week of Jan 17-21, and they’ve shown this more or less for the past couple of days. Please bear in mind that beyond a week, the errors can become very large in both position and strength of these features. If the PV does significantly southward, then very cold air would likely dominate the week of Jan 17th.
But, one arctic blast at a time, please…I’ll start blogging on that come Monday…so keep reading!