high risk

FWIW, I found a case almost 3 years ago to the day in which we busted on a snowfall here locally as low-level arctic air was slower to arrive than progged. The RGEM was the outlier among models right before the event, showing a slower push of the front, and it was right. I don't want to make too much out of two cases in three years, but it's something I will file away in the back of my mind.

I’m assuming that final band is on the leading edge of the arctic air.

The Kuchera daylight ratios show us getting 37 straight hours of darkness.

Clarification needed: the 12z soundings do not make it into the 12z HRRR. They’ll be used in the 13z cycle (which of course only runs 18 hours out…..)

That's awesome! But this really isn't about pulling in mild air from the ocean. It's a question of where the thermal boundary sets up at the start of the day and how quickly it moves southeast. The snowiest models move it quickly away, while the other solutions keep it close by, and we lose some QPF to a mix, before the cold air finally wins out during the afternoon.

1.5" in southern Howard County

I think that's really generous, but we'll see......

Looking at the RAP with Kuchera ratios for a snow event is like eating an entire stick of butter when you want a modest snack and then washing it down with a glass of canola oil.

It's driven by lower-atmosphere temperatures. It's great at chopping amounts in marginal temperature environments, and the premise that SLRs will be better than 10:1 in cold environments has some truth, but it's not as simple as colder=better SLR, so it goes nuts when the air mass is cold.

Thank you. The Kuchera drives me nuts. It always feels like this is 10:1 and this is the same case with Kuchera:

I'm in the "00Z NAM at f84 looks closer to the 18Z Euro at f90" camp.

Up to 6" here in southern Howard County, with moderate snow falling under this good band.

You should have just said that you were looking at the NAM (which is 2 hours slower than most other guidance).

It actually matches the HRRR (and several other models quite well), although I'd lean towards the latter parts of those time periods. The NAMs have a clear bias towards too slow of an onset in precipitation, and that is true whether it's summer convection or a winter storm.

Yeah, by hour 96, the 00Z cycle handled the shortwave over Montana quite differently than the previous 2 cycles.