Wednesday, 11:30 a.m.
I ask that question, as there has been little hint of it so far this fall. However, starting with the 0z Nov. 4 deterministic European model run, there have been some hints at this possibility by some of the other models, so it's not something we can summarily dismiss and say it won't happen because the pattern is a warm one. Well, in the grand scheme of things over the next two weeks or more, the pattern, for most, WILL be warm. But that's not to say it can't get cold enough for just a long enough period of time to allow some snow to fall.
As an example, a nice blanket of snow fell across part of Nebraska, southeastern South Dakota and far northwestern Iowa in the past 24 hours, a snowfall that then extended diagonally across Minnesota from southwest to northeast. Visually you can see it here:
Farther north and west, it was too dry, and the ground remains bare. To the southeast, it was too warm, thus no snow. Yet if you look at the region as a whole, it is in the midst of a mild weather pattern for early November. All it did was get cold enough at the right time with a storm cutting by to the south for it to snow, and you can visually see the results.
As we look out over the next 10 days, it is hardly a cold weather pattern for most places from the Rockies to the East Coast. Here's a look at the 06z Nov. 6 GFS ensemble forecast for seven-day means of temperatures from this Friday through next Thursday:
Note that the Rockies and Plains to the Mississippi Valley are, by and large, very mild for that one-week period! In contrast, the East is not so warm, especially the Northeast, which at least opens the door to frozen precipitation if the moisture and cold air are well timed. Up to now in most of the country, especially from the Great Lakes to the Northeast, that timing has been lacking.
Modeling has been throwing out some hints over the past two days, though, of the potential for snow or at least a 'wintry mix' of precipitation next week. It really began with the 0z Nov. 5 European operational model that closed off a deep upper-level low over the Ohio Valley to the Northeast later next week. It has since backed away from such a bold prediction, but some of the other models are now bearing the torch, and even some of the ensemble members of the various models are now suggesting snow is not a ludicrous thought.
How COULD this come about? The answer could well lie way upstream over the Pacific. If you go back to the GFS ensembles and look at the forecast of mean 500mb heights and anomalies, the one that boldly sticks out is the extreme amplification of the troughs and ridges over the Pacific. Look at this image:
That's for next Monday evening, And it shows an extremely strong upper-level ridge over the north Pacific right up into the Bering Sea. That forces an upper-level trough to dig in off the West coast, and there's another piece of energy ready to dig that trough even deeper. With such strong forcing upstream, we'll almost assuredly see an upper-level ridge form over the eastern Rockies and Plains, bringing a lot of mild air to bear. If you look again at that image above, there's a pretty strong upper-level trough rolling through Quebec and therein lies part of the issue regarding snow chances next week over the interior Northeast.
One disturbance will zip across the northern tier of states this weekend, pulling a cold front swiftly off the Northeast coast Sunday with limited moisture. There can be a little snow in far northern reaches of upstate New York and northern New England, but that's nothing out of the ordinary for this time of the year.
A second piece of energy will move in behind the first Monday and Monday night, and that should be enough to pull colder air southward through Quebec and into the Upper Midwest and Great Lakes. This is where it gets dicey, though, as the models clearly diverge at this point. Some suggest a bigger feature will arrive by Wednesday to attack the cold air air that will have moved into place by then. Other models skirt the cold air with these features, leaving much of the Great Lakes and the interior Northeast high and dry.
It would seem the window of opportunity runs from Tuesday night or Wednesday to Friday, and it could be from a couple of separate features. The verdict is clearly not in on this, but there are definitely some hints that snow may not be that far off for the interior Northeast later next week.
Comments that don't add to the conversation may be automatically or manually removed by Facebook or AccuWeather. Profanity, personal attacks, and spam will not be tolerated.