hawkeye_wx

I'm up to 2" with the best snow of the night currently falling. One nice thing about getting a solid glaze before the snow is I can measure anywhere and not just on my snow boards.

The backside deformation zone is filling in across eastern Iowa. It's not heavy, but it's solid accumulating snow that will continue all night.

I've received about an inch since it began around 7pm.

Snow is picking up here, into moderate territory. A long-duration light to moderate snow through Sunday morning may get us to 3-4".

We've switched to light snow. It's possible we could still pile up 3-4" if the deformation zone works out favorably.

A few flakes are finally beginning to mix in over here.

Unfortunately, today's models were too aggressive with the switch to snow over here. They had it all snow by 6pm, but it's still all sleet.

We have very slowly risen to near 32º now, still raining. The HRRR and NAMs insist we will switch to snow over the next hour.

For the last several runs, the HRRR has the light, but solid, deformation zone parking over Cedar Rapids/Iowa City through mid morning tomorrow.

The solid rain has arrived here. It's still 31º, so there is a shiny glaze covering the snow.

The HRRR is ramping the snowfall back up for east-central Iowa. The 18z is the best run since yesterday.

... and the GFSv16, Canadian, and UK. If the northern stream outruns/bypasses the southern stream, which is what models are beginning to show, then anything could happen after that. The southern wave could get dragged along and sheared (tonight's UK), or it could hang way back and get picked up by the next northern stream wave (other models).

The 18z Euro is the first Euro run to move Cedar Rapids out of the 6+" 10:1 snowfall. On top of that, the 00z HRRR is even warmer once again and, like the NAMs, brings plain rain up into Cedar Rapids. This formerly "locked-in" snow event is fading fast over here. Perfect low track, strong storm, but not enough cold air.

Yep. I'm not expecting more than a few inches of slop. Bummer.

3k NAM says forget the mixing, let's just go with rain.

The HRRR has a 7:1 ratio over here. That'll be fun to clean.

18z HRRR... last evening this model had all snow down to I-80 in eastern Iowa at this time. Meanwhile, the Euro still does have all snow. One of them is very wrong.

The CAMs keep warming it up over here and lowering snow totals, but the globals, particularly the GFSv16 and Euro, won't budge from their colder and snowier solutions. 12z Euro 10:1

Keep in mind this should be pretty wet stuff with a lousy ratio.

Those of us in Iowa are wondering what happened to our big snow event that appeared as locked in as any storm could be a few days out. Nearly all models are either cutting the precip down, warming us up, or both. Even the HRRR, which nailed the colder, snowier late December storm, has now warmed us up and drops at least a few hours of mix crap here. The 6-9" snow event has been cut in half.

00z Euro - The east trend continues. Central Iowa's snow is fading, but east-central is still good....for now. This run is also a bit south.

While we've been analyzing the thermals, there is a new unfriendly trend for Iowa. Some models are now veering the heavy precip farther east into Illinois and bypassing much of Iowa. The UK has been consistently one of the snowiest models for central to eastern Iowa. Tonight's run cut out a huge chunk of our precip.

So you're saying the precip is not going to change to rain up to Chicago by Sunday morning?

It's going to be a nail biter over here Saturday afternoon. The NAMs have warmed a bit more, which now puts Cedar Rapids on the southern edge with a bit of mix at the start. The HRRR, on the other hand, is colder and changes the precip to snow before reaching Iowa City. I'm hoping it works out like the storm in late December when I received 8.5 inches, with 5.4" in three hours early in the event. That storm also had borderline thermals. Models were wobbling on the fence. It was unclear if Cedar Rapids would get 8" or 3". However, there was a clear model winner (HRRR) and a clear loser (NAMs). The NAMs insisted the warm air aloft would push sleet up through eastern Iowa. The HRRR insisted the snow would hold strong down to Cedar Rapids, at least. The HRRR was absolutely correct. First few hours of the HRRR are in range. This would clearly be much better for Cedar Rapids/Iowa City and also Peoria.

3k NAM