Jan 24-26 Weekend Snow and Sleetfest Model Thread Part Tres

[bncho]

I think HRRR is a little bit faster and a little bit wetter.

(2/10)

[Interstate]

Lost 2 degrees in last 15 minutes. 23.7

[Eskimo Joe]

Looking to our SW, places that were supposed to be ice or sleet are snow. Soundings reveal the forecasted warm layer failing to materialize. Maybe it gives us some hope?

 

 

[IronTy]

Topped out at 30F today at Deep Creek, dropped like a stone and now I'm down to 6F.  I have no idea how high the wind gusts are but they have to be 40mph here on top of the mountain.  It's been all day.   I have a few flakes blowing around but otherwise partly cloudy. 

[Jebman]

14 minutes ago, jayyy said:

Bottoms falling out. Down to 20 already

I just completed my daily weather obs across the country. VERY COLD all over!

Best of luck with this storm!!!! You guys are in for a treat! Good Times!

[wxmeddler]

35 minutes ago, mikeg0305 said:

Well then what does sleet look like?

Good Question. I made an example here of the general concept. In the images below I've "Unskew'd" the Skew-T so that temperature is now vertical line on the X axis. Y axis is height obviously. 
The only question to ask is which area / shape is bigger? The Red (Above Freezing) or the Blue (Below Freezing). In this profile the blue is bigger, and therefore Sleet would likely be the most dominant precipitation type.
 

So what about this one? Red is bigger, therefore Freezing Rain would be most likely.

In the real world of course there is more to consider like dynamic lift in banding, precipitation rate, etc. but it's useful.

[yoda]

00z HRRR is still snow DC metro at 15z... but pingers are nearby

[Paleocene]

Latest HRRR has south of i-66/50 holding as snow thru 15z, then flipping around the metros at 16z. 0.6" QPF pre-flip

[clskinsfan]

1 minute ago, yoda said:

00z HRRR is still snow DC metro at 15z... but pingers are nearby

It's a really nice thump. DC 8 inches plus. More north and west.

[yoda]

Hmmm... 00z HRRR really spiking temperatures too...

[TSSN+]

Just now, yoda said:

Hmmm... 00z HRRR really spiking temperatures too...

Looks like the other model like euro and rgem

[yoda]

1 minute ago, yoda said:

Hmmm... 00z HRRR really spiking temperatures too...

Rain in most of DE, S MD at 20z... rain not far away from DC metro tbh

[DDweatherman]

Even if these models are right, it’s such a bad idea to use them in their extended range. The HRRR is wrong often at hour 6 much less post hr 18.

[mitchnick]

Really odd how the sleet makes it just past Hanover at 3pm, but then starts sinking back down the next 2 hours so we're back to snow at 5pm. But, the slp is still in WV gradually moving north.

Take a look at it TSSN+.

[mikeg0305]

One of those YouTubers is saying the Arctic high is a bit further south on the recent model runs than prior runs.

Any of you see that from your perspectives? Does that make a difference?

[nj2va]

48H HRRR is better off being in the banter.

[yoda]

Just now, nj2va said:

48H HRRR is better off being in the banter.

True, just a bit awkward seeing 34 and rain for Wes at 19z

[TSSN+]

2 minutes ago, mitchnick said:

Really odd how the sleet makes it just past Hanover at 3pm, but then starts sinking back down the next 2 hours so we're back to snow at 5pm. But, the slp is still in WV gradually moving north.

Take a look at it TSSN+.

Coastal pulling away maybe pulling back in the cold air. 

[clskinsfan]

It looks like it is trying to jump off of OC. Would like to see more plots. I wonder if some us would go back over to snow. 

[Paleocene]

2 minutes ago, yoda said:

Rain in most of DE, S MD at 20z... rain not far away from DC metro tbh

 These are the warmest surface temps I've seen. WAY warmer than the NAM 3km and globals at the same time. I say toss.

 

 

[Weather Will]

WB 0Z HRRR is a glacier.  Not sure what people expect from this storm, but it looks like a serious storm with prolonged cold in place. Totals added to my list a couple pages back.

[mitchnick]

Just now, TSSN+ said:

Coastal pulling away maybe pulling back in the cold air. 

There's really no coastal. Just one circle of isobars. Warm air advecting from the south must have been shut off, but I don't know how or why.

[Scraff]

Deep breathing exercises right now. Missed a lot I’m guessing. Anyone got the cliff notes for the last 6 hours? 

[Amped]

48hr hrrr has the changeover line matches the euro almost perfectly.

[psuhoffman]

4 minutes ago, TSSN+ said:

Coastal pulling away maybe pulling back in the cold air. 

 

7 minutes ago, mitchnick said:

Really odd how the sleet makes it just past Hanover at 3pm, but then starts sinking back down the next 2 hours so we're back to snow at 5pm. But, the slp is still in WV gradually moving north.

Take a look at it TSSN+.

It’s because the warm layer is at its greatest extent there and thin and it’s wobbling based on rates. Around 20z we’re in a dry slot then it sinks south during some heavier precip 

[LVblizzard]

9 minutes ago, Paleocene said:

 These are the warmest surface temps I've seen. WAY warmer than the NAM 3km and globals at the same time. I say toss.

 

 

HRRR has a warm bias at the surface…which is strange because it’s often too cold in the mid levels.

[CAPE]

30 minutes ago, Weather Will said:

WB 0Z HRRR 4 am Sunday; 9, noon flip in DC complete; 3 pm flip to PA line: Precip totals 7 pm Sunday: A True glacier.

HRRR look good. Primative grunt.

[Solution Man]

NAM with snow about 8pm tomorrow 

[TSSN+]

20 minutes ago, yoda said:

Rain in most of DE, S MD at 20z... rain not far away from DC metro tbh

Flood watch was just issued in Georgetown I hear. 

[Wetbulbs88]

The HRRR is vaguely useful at 6 hours. At this range it means almost nothing.