Chinook

I did a little something different with this loop. It shows the 700mb-400mb relative humidity and SLP, so you can see the moisture streams joining up on the East Coast. http://www.greatlakes.salsite.com/Mar_6_2020_700mb_loop.html

It looks like a 500mb low will be in Arizona and New Mexico, on Friday morning, possibly tracking toward SE Colorado and SW Kansas. We will have to see how the models handle the synoptic details in the next few days.

This is weird.. and models have quite a bit of agreement at this time, which is also a little weird.

At the end of this East Coast storm, I may put a loop of the 500mb vorticity on my web site, because it's a 500mb phase. The GFS has 964mb off the coast by 06z, which is still today, in my time zone. Remarkably, this is yet another situation that screws the Boston-Washington corridor out of snow. Coming up soon, we'll have later sunrises, later sunsets, and the 00z models will be on the internet later in the evening. And 06z will be "tomorrow," technically.

Low-level rotation track for the tornadic supercell at Nashville

This was the radar from the reported tornado at Crofton KY earlier (8:00PM CST/ 9:00PM EST). At the current time, some tornado warnings are ongoing around Waverly, Tennessee/ Tennessee City

This WPC blend of models shows the potential for 0.3" of QPF or 3" of snow or more for lower elevations, on Sunday to Monday. It's possible that 5-day storm totals may be at least 8" above 8000ft.

Models continue to show a lighter snow event on Monday (possibly morning). I kind of hope it's wrong. Too much of this stuff has happened on Mondays and Tuesdays.

Yesterday, my area had temps of 27 degrees in the afternoon, with winds to 23mph gusting to 36mph at the airport. (wind chill of 13 degrees.) Even if you have lower winds in the city environment, the wind chill values are still much colder than the average temperatures of upper 40's to 50 degrees, for this time of year.

Interesting story: on this day in 1965, a great storm tracked from the lower Mississippi Valley to bring 11" of snow to Detroit. As you can see on this map, over 10" was reported in MO, IL, IN, and MI, and close to Toledo. It also seems likely that there were some 10" amounts in Kansas

This snow squall lasted for about 20 minutes (1503z is 8:03AM) KFNL 241503Z AUTO 31024G35KT 1/4SM SN FG SCT005 BKN012 OVC075 00/M02 A2985 RMK AO2 PK WND 32035/1457 PRESRR P0000 FZRANO

For all Detroit/ Toledo people out there, the Euro shifted south, with the 850mb low tracking near both cities with 850mb temps of -6C. 5.7" to 6.8" near Detroit, 5.3" at Toledo.

Some of California and Nevada have increased in drought coverage recently. It seems that the Sierra Nevada snowpack is not going to get a lot better soon. Overall, the West has less drought than one year ago. As you can see, most of the snowpack values are pretty good, and Montana has about 117% of snow water equivalent in the mountains. Not too many areas of the West have been more than +2F for this February, so that is not too crazy.

On February 15th (8 days ago) I posted a GEFS-500mb/SLP image for 240 hours (Feb 25th) that seems to partially correlate with today's weather (Feb 23rd.) There has briefly been some snow between Denver and Boulder today, but it must not have been too interesting. Colorado Springs is still getting some snow right now. At my place, it is not snowing or raining currently. There may have been some drizzle or snow near Loveland today, but it has not been below freezing since yesterday. Coming up Tuesday and Wednesday, we should have some chilly weather. It seems like we will get much-needed moderate temperatures and fair weather, possibly until March 2nd or March 3rd.

I think it's because there's a higher lapse rate near the 500mb low. Maybe models can't decide what to do with the banding of precipitation with some slight variations in lapse rate and higher values of vertical velocity. I'm not sure though. The liquid equivalent of snow and rain should be 0.20" to 0.30" near Denver. There is a winter storm watch for the Palmer Divide, and winter weather advisories for the mountains.

The next storm on Sunday should have some areas of snow from Denver, eastward to Goodland, KS. Otherwise, models differ on details. Areas of the plains should be above freezing and may get rain initially. The way things are going, this storm will find a way to bring snow to my house.

My place has gotten about 1.5" of snow today.

Weird anticyclonic snow band. It's a pretty interesting radar loop, if you happen to catch it soon.

A snow band developed very recently here. Hopefully this won't last too long.

I am not sure if you saw my recent post about the recent Iceland low pressure. There have been several strong low pressures have been in the Iceland region this winter. Seemingly, no matter what happens, Europe continues to get warmer air masses. I have heard that January 2020 was tied for the warmest January on record. (Source: Brian Brettscheider/ Climatologist49 on twitter.) I have barely seen any TropicalTidbits maps where the surface temperature was below normal in eastern Europe.

If you live on the Palmer Divide (Palmer Lake and east of it) there will be some 2" hailstorms. Along with that, hailstorms can lead to street flooding, and "hail drifts." As you can see on the SPC severe plot image, the high plain area is prone to 1"-2" hail, plus tornadoes on the east side of the Palmer Divide. The mountainous areas even get 0.75"-1" hail sometimes. See reference map with county boundaries on the right. This severe data is from 2010-2017. Luckily, the chance of fatalities in Colorado tornadoes is nearly zero. All of these places should get decent snowfall. North facing areas of the Palmer Divide will have snow and blizzard conditions from time to time. They warm up very quickly with 40mph chinook winds at some times during the winter. Places closer to Boulder and Golden have a greater chance of extreme chinook winds (70mph.) This is one of the places where you could have a winter storm watch and a tornado warning on the same day (Springtime only.)

In the short term, the NAM/Euro/Canadian show snow should happen Monday night and Tuesday, along with higher amounts over 18" in the mountains. In the long term, We may have something interesting to watch on the ensembles for cold temperatures and snow, for the February 25th time frame. It's not like I really need to shovel a lot more right now.

This doesn't really have a lot to do with North American weather, but this is about 2 mb away from breaking the non-hurricane pressure record for the Atlantic. (This should happen tomorrow.)

Low temperatures were between 4 and 14 degrees around here. Now it is 50 degrees with 30mph wind gusts. The front porch is wet all over the place.

Here's my snow totals FEB 2020 feb 3-4: freezing drizzle and 7.2" of snow feb 4-5: 1" feb 5: low temp of -5 to -15 feb 6: trace of snow + before midnight, wet roads feb 7-8: 5" feb 9: 0.5" feb 10: 2" feb 12-13: 2.5" 18.2" Loveland 2N co-op station (up to yesterday): 15.5", 0.88" Note: we really didn't get -16 degrees on two different days.