Update 12/5/2016 - the cold is on it's way

In the post I did last week on the 30th (read it by clicking here), I showed a system that was along the northern border of Washington state and was expected to dive way south into southwest Texas.  Did that happen?  Look at this mornings satellite image:

click for a larger map
This system did develop as expected.  On the map, the system is denoted by the red "L" near El Paso.  It has brought very heavy rain to much of Texas, parts of Oklahoma and is now soaking the lower Mississippi Valley and eventually the parched southeast U.S.  Good for them!  What I was not expecting was enough lift of the atmosphere across the central U.S. from a passing upper level trough (mostly unrelated to the upper low but the northern branch of the westerlies) to produce much precipitation.  Some areas of the central U.S. did receive some beneficial rains (and a little bit of wet snow)!

Here is a map of precipitation from over the weekend:

Click for a larger map


Anything from about Amarillo to OKC south is related to the upper low.  The remainder north of that line is a gift from the northern branch of the westerlies!

In the previous post I also talked about an upstream system that could bring snow Tuesday and Wednesday, but also cautioned to seeing predictions.  Computer models are and have been all over the place!

On the satellite image above, there are actually 2 systems.  One was over northern Wyoming and will become a pretty decent storm for the northern Plains and upper Midwest/Great Lakes region.  Nothing for the central U.S. other than providing a cold front that will sweep across the high plains Monday night into Tuesday..

The other X (2) was approaching Washington state and you can see the expected path it should take.  It will be a compact system and thus will bring a narrow band of precipitation (snow) as it moves out across the central U.S. on Wednesday.  It looks like any significant snow will be confined to northeast Colorado and western Nebraska and perhaps far northwest Kansas.  Lighter snow (less than 2 inches) will fall on a line across mainly the I-70 corridor as far east as Manhattan.  Some of that snow could creep a little farther south, but it shouldn't be much (a dusting to 1 inch).

Through the next 7 days, here is the outlook from the Weather Prediction Center:


After this second system moves through, a brief period of even colder air should spill south across most of the area Wednesday and Thursday.  That would be just a couple of days faster than I originally expected (in the previous post).  But as I also previously expected, it will likely be just a brief visit as there will be a warm up (to seasonal values) Friday and Saturday.  But, that might just be the start. There is some pretty cold air to be tapped into and it looks like this cold air will slosh back and forth for at least 10 days to 2 weeks (maybe longer) centered on the central and northern plains.  Thus, areas of the high plains will see wild swings from really cold to brief warmups.  The upper midwest and northern plains may be set for the deep freeze for an extended period well into December.  The first slosh back into the really cold might be as early as the end of the weekend.  Every time that happens, there might be a brief period of fluffy light snow.

Here is the morning map of temperatures:
 
December is typically (based on climatology) the driest month of the year.  At this point it sure doesn't look like it will be any different.  As the repeating pattern length starts to reveal itself, I might be able to pin down the next chance for a "significant" chance of a storm.    I'd like to say between the 18th and 22nd, but the confidence in that period is near zero but it's stuck in my mind.  I'll try and update towards the end of the week or weekend so check back.  In the meantime, prepare for periods of really cold air and then it's back to near seasonable temperatures for a few days before going back into the deep freeze.Break out the feed bales!