That vacation winter's been on is coming to an abrupt end as a pattern change starts to unfold along with a central Midwest snowstorm. The hardest hit areas will be Missouri and central Illinois where totals of over a foot are possible. Here's a couple situation reports from NWS offices in St. Louis, Missouri and Lincoln, Illinois.
You can see all the warnings and advisories in effect as of late Friday. These are likely going to get extended north a bit by Saturday based on Friday nights data.
My area remains on the northern periphery of the snow shield. Accumulations in my forecast region will be more manageable but still significant in the south, especially along and south of HWY 30 where snow is expected to fall through Saturday. Here amounts of 4-8" looks attainable...the 7-8" amounts south of I-80. There will be a sharp cut-off to the northern edge of the snow near HWY 20. Here's the latest snowfall forecasts as of Friday night. The EURO is the furthest north and most aggressive with amounts. It may be a tad high on totals but I would lean on it this late in the game. Here it is.
A larger perspective of the EURO.
The 3K NAM
After the snow moves out, next week looks quiet and seasonably cold until Friday. Then the dam breaks and much of the nation enters into an energetic pattern featuring several potential snow systems and Arctic outbreaks. Here's an example of what's on the table. This is the 500mb jet stream flow January 22nd on the GFS. I haven't seen a set-up that impressive in quite some time. It may not happen exactly as depicted but the model is grasping the depth of the coming cold.
This is the 5 day temperature departures at 5,000 ft centered around the frigid vortex's visit.
The one day temperature departure shows the intense cold over the central U.S. January 22nd
Hopefully ensuing model runs will ease the intensity of the cold but for several days they've consistently pointed at the threat of bitterly cold air around this time frame. Friday's GFS has lows in my area 15 to 20 below January 23rd.
The wind chills are just ridiculous. Very dangerous levels 40 to 50 below! I'll believe that when I see it.
If you didn't get snow this time around don't despair, there will be other chances. The GEFS ensembles show this for 16 day snowfall.
The EURO EPS ensemble mean has this for 15 day snow.
It sure looks like it's payback time for all that mild weather of the past 6 weeks. I'll keep you posted. Meantime have a swell weekend and roll weather...TS