Chinook

Maybe the severe weather will ramp up soon in far northeast Texas into southwest Arkansas, including the current tornado warning at Woodland TX/ Red River area. Otherwise... 30 severe reports so far would be a very low # of severe reports if things don't get active.

New tornado warning south of Fort Worth, heading for FWS radar.

Maybe this is one of those "oops" moments for automated sensors - Chariton, Iowa has had RA and +RA with temps below freezing KCNC 102235Z AUTO 36021G29KT 1 1/4SM +RA FEW007 BKN013 M02/M02 A3003 RMK AO2

Why? Is this super confusing or something? The GFS and NAM-3km have some ice in these areas.

New tornado warning says that this is a radar confirmed tornado. (Zeb, Oklahoma)

Winter Storm Watches have been issued for Wichita, Chicago, Michigan, Iowa, Wisconsin. It seems that several overlapping weather watches/warnings/advisories can make the NWS web pages confusing

This is the NWS forecast for the next 66 hours. I'm sure they will be basing their winter storm watches and winter storm warnings on this or something similar. The Weatherbell web site also has a graphic for the freezing rain expected, but it's confusing right now, but it says 0.48" of freezing rain for Grand Rapids, MI.

Regarding Saturday, the 12z NAM has SigTor values of 3-5 in southern Mississippi at 12z. Unlike many days in the summer, severe weather should be happening around 12z.

As an interesting side note, you can use the PivotalWeather ECMWF clickable soundings to check for severe weather parameters.

We need to have something more specific than simply a negative PNA index number. We need to have a trough that develops near the West Coast and tracks toward here UT and CO (Four Corners), with perhaps even a ridge just off the West Coast. The PNA index doesn't capture that well, but the index could be negative when that happens. On the other hand, we could get a lot of cold air on the Plains and have upslope event with more arctic air and less of an organized 500mb trough. The PNA or NAO indices may not capture that well. In rare circumstances (like an El Nino,) we could use a large California 500mb low to track toward us, via the Four Corners.

NWS Boulder lists top weather events of Colorado within the last 10 years

Storm reports show up to 5" - 6" in some parts of the Denver metro, with over 6" at the foothills/Palmer Divide. Also, up to 8" at Pine Bluff, Wyoming. It must have taken a long time. Here in Loveland, snow had mainly ended when I last posted (12 hours ago), we had some downslope wind off the Cheyenne ridge, with weak radar returns, so almost nothing happened beyond 10:00AM. This might be something like a 48-hour (near-blizzard?) storm for eastern South Dakota.

My area got 1-2" of snow today, with maybe some wind gusts to 20-25mph right now.

The GFS has 12" of snow for Akron CO (Washington County, CO) and the NAM has 1" and the NAM-3km has something like 2"-5" in the county. This is madness! This is mixed precipitation madness that has been happening today in KS and Nebraska:

A winter storm reaching from Mexico to Canada.

NWS-Cleveland posted these stats on twitter: #Toledo #Ohio broke a record high temperature today of at least 63°F (old record was 62°F back in 1888). #Youngstown has tied the record high temperature at 64°F (old record was 64°F set back in 2016/1982). I was just in Toledo a few days ago. Also, on Monday (Dec 23rd) I was at Cleveland Hopkins Airport and there was a high of 58, low of 36.

We should be close to the 500mb/700mb lows, but without a strong upslope component. So upward motion will not be concentrated on the foothills for very long. Then stronger lift will begin farther east as the surface-to-700mb low intensifies to the east, out near Goodland and into central Kansas. By the way, it looks like the Euro had another (minor) victory on this one, as the GFS had the snow to the east of us for several runs. NWS already has 8-10" for northern Nebraska through western Minnesota with this storm.

For Saturday-Sunday, the NWS is expecting 1.5"-3.9" of snow for the Front Range cities. There is a winter storm watch east of DIA. Heavier snow towards northeast Colorado and Nebraska, as well as southern Colorado and northern New Mexico.

Some ensemble members of the GFS and Euro show some hope for snow in Denver. These must have a bit of a different look at 500mb than the regular GFS at this time. Interesting fact: NWS-Fairbanks is forecasting -46F for the Tanana valley this week.

Today's Euro shows that the storm will provide about 2-3" of snowfall all over the plains of Colorado on 12/28 (96 hours) but this is somewhat of an outlier. I think it handles the 500mb low differently than the GFS and Candian.

I got back from my trip to Ohio. I was in the Akron/Canton area, and I drove to Toledo and back. We had 5 consecutive sunny days, with no low stratus clouds. (Thursday-Monday) There is a very low chance to have 5 sunny days in a row at this time of year, with no overcast stratus clouds at any time. Here's my thinking. The chance of having roughly 24 hours of clear(ish) skies is 20% or less. Weather tends to change in some predictable ways over the course of 5 days. But if you just think of this as a series of random events, then the chance of 5 sunny days is (0.2)^5 = 0.00032 = 0.032%

Euro/GFS/Canadian all have a closed 500mb low in AZ/NM on December 28th, so it's definitely something to watch for the southern Rockies and areas of the plains into Kansas.

Since November 25th, Fort Collins has been -2.2 F in temperature, with 294% of normal snow and 439% of normal precipitation, (393% of normal at my place) . Snow is still on the ground here in some of the areas that face the sun. So, December has felt snowy, even though little snow fell out of the sky. Not much will happen here soon, and temps will be 40's and possibly some 50's. But that's good for my trip. I will be flying out tomorrow, and there should be few weather problems anywhere before I get back.

Debris/ tornado report evident at Baldwyn and Guntown, Ms

tornado warning and tornado reports near/at Bogue Chitto, Mississippi.