Anymore it seems like it's harder and harder to get the cold air in place that's necessary to produce snow. And then when you do, you can't get a storm to finish the job. That's the situation we're going into the next 6-10 days. Take a look at this temperature departure for December 13th on the EURO. Bitterly cold air with 850 temps to -24!

Here's the 500mb jet delivering the cold at that time. An anomalously deep trough centered on the Great Lakes leading the charge. At the same time the dreaded death ridge that cuts of moisture remains entrenched over western Canada and the Pacific Northwest.

Unfortunately, much of the next week the strength and position of the ridge/trough couplet is such that despite the cold there's no moisture available to cause any significant snow outside of the lee of the lakes. Here's the PWAT levels (precipitable water vapor) which are remarkably meager over the entire nation. In my local area PWAT's are near .04". The Gulf of Mexico (our moisture source) is completely closed for business.

The baroclinic zone where storms like to form is well to the west. It is clearly evident though on the above graphic in a narrow band from Western North Dakota through Kansas and into the southeast United States. That is where clippers are born and the area to watch for some fast moving but meager snow produces. As the cold vacillates back and forth the next 6-10 days a few of these systems are possible but they only generate very narrow snow bands. Amounts are usually not more than an inch or two due to the limited moisture and rapid movement. These are pretty difficult to detect past 2-3 days so they are day to day issues. The puny one arrives Friday and most of that dusting looks to be to my north. To be frank, there's nothing that looks promising for snow for at least a week and probably more in my area.

I did go through the EURO EPS weeklies from Monday night and I did not see anything that got me excited. Much of the next month it holds the existing pattern (including the death ridge) in place forming a predominate northwest flow. That creates a 46 day temperature departure that looks like this. Cold east mild west.

The snowfall forecast came out this way ending January 19th. That's nothing special for 46 days but I'd take it. In all honesty, I'll believe it when I see it.

Well, the cold is here and so is the wind. Now I wait for the white gold. Some things never change! Roll weather...TS

© 2020 Terry Swails