Chinook

Models are coming into better agreement with the storm system moving south from the Rockies into Texas. It is kind of strange to see this. Most of the time, when a model shows snow for Dallas, it doesn't really happen. Over the weekend, temperatures will be close to freezing around and south of I-20 with 850mb temps of possibly -2C to -4C. There are a variety of model solutions on snow totals, so this should be interesting to see how this turns out.

The models now have some agreement on some version of a 500mb low near the Four Corners and snow for northern Colorado on Saturday. ECMWF has the snow farther south around Trinidad CO, moving down toward SE New Mexico. It's possible that this is a storm that could just disappear, as so many have. By the way, my place hasn't been above 50 since Dec. 26th. They keep saying it will be 50, but the snowcover and lack of mixing has kept us cooler than Cheyenne and Denver at times.

In related news, the low pressure in the western Aleutians in the Pacific was analyzed at 921 mb at December 31st, 18z. Since it was so late in the day, in UTC, it was indeed January 1st in some part of the Eastern Hemisphere. I have not seen a 921mb low for extratropical lows. I believe the record is 913mb for the North Atlantic. I am not aware of any extratropical lows of this value in the Southern Hemisphere, but there could have been something. Edit: Raindance, I wonder when (and if) the models will pick up on such a storm system at some 240 hours out. Perhaps we could say model ensembles already have a hint of a upper trough and surface low near the Great Lakes at 280 hours, and that may be the hint of the connection right there.

It looks like we've got an El Nino going here with mild Pacific air an important factor in the Dakotas, and cool conditions in the Southwest and Southeast.

Pretty nice composite picture and tweet by Jim Cantore

It certainly seems like this could be a regional tornado outbreak, with SRH values of over 300-400 m2/s2 and shear values of 60 kt, and CAPE values of 500 J/kg to 1500 J/kg in southern Louisiana. Convection allowing models show a squall line or at least quite a few cells in western Louisiana, and several more isolated cells near the LA/MS border

There is a mix of snow, rain, and freezing rain in Kansas. As always, the colors I get on this map are not completely the same as the type of precipitation reported at airports. Kansas City: light freezing rain.

My place got a little over 2", probably like 2.2".

Here is the 00z Euro snow totals chart up to the point -before- the 500mb low regenerates a snowy surface low in the southern Plains. Overall, the GFS, Euro, and Canadian have come into better agreement on QPF in Colorado, where snow should be in my area from 12z Monday- 06z Tuesday. Note: See MO/AR/OK/KS thread for discussion of possible large southern plains ice and snow storm.

The storm is getting closer. This is the Euro depiction that shows that northern Colorado would get 1-3" with sort of a warm advection sector to the storm. The higher elevations of Colorado will get 3-6" or better with upslope, and maybe over 6" as the upslope continues for perhaps some hours (beyond what's shown on this chart). As for the Midwest, Nebraska/Iowa and the Upper Midwest will have the potential for snow over 6"-12". Kansas and possibly northern Missouri could have some sleet or freezing rain. It seems several models have shown low snowfall for eastern Colorado, and this is kind of disappointing, considering the 500mb is so close to the right spot.

My place dropped from 60 degrees to 29 degrees. Look at South Dakota-- they were in the mid 60's, then blizzard, apparently 49.7 degrees colder.

It looks like we really may have something to track over the next 6 days. There could me more snow in Kansas than at my place.

change over to snow in Minneapolis

14 years ago (December 20-21, 2006) view from apartment building

For those interested, this radar web page provides a little better functionality to the new NWS web page. The boxes labeled "3" to "15" on the left hand side are zoom levels (you can zoom out by clicking a different zoom level) https://mrms.nssl.noaa.gov/qvs/product_viewer/

wind warnings and blizzard warnings. NWS point forecast for me shows 52mph wind gusts before midnight.

Today, my area has a few lenticular clouds and mostly clear skies. I am hoping to see Saturn and Jupiter next to each other in about 1-2 hours. Yesterday, my area had about 39 degrees in mid-afternoon when other areas were warmer, with adiabatic mixing. Today, my area is up to the upper 50's. edit: I got lucky. Sometimes the lenticular cloud at sunset is tough to find. I also saw Jupiter and Saturn in the binoculars a few minutes ago.

Some of the ensemble means do indeed have a trough in Utah/Colorado-- about what you want to see, I suppose, if you were going to put your hope in any storm in Colorado at 240 hours in the future. edit: to a degree, this month has showed signs of looking like an El Nino upper level pattern, with positive PNA and cooler temperatures in the Southern Plains and Southeast, and even, nearly a true Miller-A storm for the East Coast.

Tomorrow, there will be something that I expect several times during a La Nina winter: high winds, from a northern jet stream disturbance. Southeast Wyoming and Larimer County (6000-9000 ft) have high wind watches tomorrow.

For those in search of a new radar site- also extra helpful for severe storms. The boxes numbered "3" to "15" on the left are zoom levels. https://mrms.nssl.noaa.gov/qvs/product_viewer/

possible synoptic setup of the polar cold front, arctic cold front, warm front, and stationary arctic front on the 23rd

My area got about 0.5" of snow last night, and Denver got around 2". Saturn and Jupiter will be (or were) the closest that they have appeared in our sky in many years.

Totals: Dec 10-12: 0.17" precip, 1.6" snow Dec 12-13: 0.08" precip, 1.0" snow

I definitely made a mistake on that. Congrats to those in Oklahoma and Arkansas getting snow. Here are some snow reports and radar from the region.

My area got about 2" yesterday it could always be worse--- Denver, Colorado , December 1990 high and low temps