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

[Amped]

5 minutes ago, yoda said:

This is near Mason Dixon line at 15z... sleety

 

The 2017 storm had a pesky warm layer around 800mb which caused the sleet line to be way north.

[Maestrobjwa]

Just now, Chris78 said:

If the M/D is pinging by mid morning that would be a poor showing from the globals.

 

Very poor. I mean they wouldn't even be close! This one falling apart in the last 36 hrs would be brutal...

[clskinsfan]

3K was a step back. Is what it is. 

[psuhoffman]

Trick, the FV3 is almost always similar to the gfs inside 48 hours. Similar to the rgem/ggem. So if you want to know about what the gfs is going to look like just look at the FV3 now. 

[DDweatherman]

The model war will definitely continue into the final day, willing to bet. 

[mitchnick]

At 39hrs, the 12k has a 1007 slp in central Mississippi, yet it just punch the sleet line thru mby like a hot knife thru butter some 1000+ miles away. Pretty crummy long wave pattern that we can't keep this storm from turning nasty.

[MN Transplant]

The surface didn’t warm as much as the HRRR.  Stays around 25 in DC and the freezing line is east of the Bay.

[clskinsfan]

2 minutes ago, psuhoffman said:

Trick, the FV3 is almost always similar to the gfs inside 48 hours. Similar to the rgem/ggem. So if you want to know about what the gfs is going to look like just look at the FV3 now. 

We would all take that right now. No doubt. 

[Heisy]

At 39hrs, the 12k has a 1007 slp in central Mississippi, yet it just punch the sleet line thru mby like a hot knife thru butter some 1000+ miles away. Pretty crummy long wave pattern that we can't keep this storm from turning nasty.

The 50/50 tpv shifted more and more NE as we get closer through the week


.

[mattie g]

2 minutes ago, Weather Will said:

Nowadays that means work from home or take leave.

Click the link. It says that remote and telework employees are expected to work and that non-telework employees will be given the hours they were supposed to work. That said, it is surprising given the current status of the federal workforce.

NAMs suck.

[Buddy1987]

FV3 looks like it has an itchy trigger finger in shooting the sleet line up around I-64 by HR 38. Naked eye looks like it’s even sleetier earlier down here. 

[SomeguyfromTakomaPark]

At this point u gotta just be in chips fall mode, if you get a ton of sleet that just happens sometimes.  Always good to get to that zen whatever happens happens mode at around 24 hours.  The atmosphere was always going to do what it was going to do and our computer simulations aren’t perfect yet.

good luck to all 

[TSSN+]

What's the Nam's sleet accumulation map looks like from weather bell? Got to be like 3-5" of sleet alone. 

[psuhoffman]

6 minutes ago, Buddy1987 said:

FV3 looks like it has an itchy trigger finger in shooting the sleet line up around I-64 by HR 38. Naked eye looks like it’s even sleetier earlier down here. 

It’s fine. 10” in DC. 12” IAD. 13” up here. 

[psuhoffman]

1 minute ago, TSSN+ said:

What's the Nam's sleet accumulation map looks like from weather bell? Got to be like 3-5" of sleet alone. 

[poprock49]

5 minutes ago, Buddy1987 said:

FV3 looks like it has an itchy trigger finger in shooting the sleet line up around I-64 by HR 38. Naked eye looks like it’s even sleetier earlier down here. 

It might be more of a timing thing. Thermals are a bit worse but heavier rates get going earlier and many end up with same total hours of snow.

[Weather Will]

WB 0Z 3K NAM

[psuhoffman]

2 minutes ago, TSSN+ said:

What's the Nam's sleet accumulation map looks like from weather bell? Got to be like 3-5" of sleet alone. 

MD is kind of dry slotted after the snow thump on the NAM so only 1-2” of sleet but a ton down in VA 

[Jersey Andrew]

1 minute ago, psuhoffman said:

It’s fine. 10” in DC. 12” IAD. 13” up here. 

You don’t believe those higher totals do you? I’m afraid the NAM is right here and DC metro is 4-6. Hope I’m wrong.

[snowfan]

If we're going to fail, I'm cool getting 4-6" followed by 2-3" of sleet that turns into a glacier.

[psuhoffman]

Just now, Jersey Andrew said:

You don’t believe those higher totals do you? I’m afraid the NAM is right here and DC metro is 4-6. Hope I’m wrong.

I went 6-10 along 95 

[Maestrobjwa]

1 minute ago, psuhoffman said:

I went 6-10 along 95 

My bar for this storm. I hope that's still possible, man. But if the NAM is right even the low end might be in trouble (that run gives Baltimore 5.2")

[TSSN+]

1 minute ago, Maestrobjwa said:

Well that would hurt...that would be another missed warning level snowfall, smh

The snow and sleet combo would be a warning level "snow" 

[Buddy1987]

2 minutes ago, psuhoffman said:

MD is kind of dry slotted after the snow thump on the NAM so only 1-2” of sleet but a ton down in VA 

Hands down one of the most impressive sleet accumulation forecasts I’ve ever personally seen. 5.7” is pretty awesome. I’ve fully accepted the sleet-mageddon and I’m excited now. 

[Chris78]

4 minutes ago, psuhoffman said:

It’s fine. 10” in DC. 12” IAD. 13” up here. 

I hope the hell it's right. Change over is 4pm or a little after at the M/D line.

Nam changeover is 6 hours or so earlier?

[SomeguyfromTakomaPark]

2 minutes ago, Weather Will said:

WB 0Z 3K NAM

2.5 inches of sleet on top of 4.5 inches of snow would be wild. 

 

2 minutes ago, Jersey Andrew said:

You don’t believe those higher totals do you? I’m afraid the NAM is right here and DC metro is 4-6. Hope I’m wrong.

The NAM has been right, but it’s also fell on its face in embarrassing fashion close up to events as well so of course consider it but I wouldn’t assume 100 percent it is correct.  Just have to keep it in mind as a possibility. 

[WxMan1]

1 hour ago, wxmeddler said:

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.

Typically the degree of the warm air (MaxT aloft) will be proportional to the depth. In other words, the highest the MaxT aloft, the deeper the warm or >0C air.

In many studies I've seen though, no matter how deep or shallow the warm air is, when you hit 3C or 37F, you're completely melting the hydrometeor. Once that happens, there's no going back to sleet or anything "pellety" unless the air somewhere within the subfreezing layer can get down to -13C/8F or lower. Unless that happens, the rain drop does not refreeze. When we see sleet, it's typically associated with an elevated warm layer temp between 0.5C and just below 3.0C. When it's closer to 0.5C, it's probably more of a sleety & rimed snow mix. When the MaxT aloft is closer to 2.5C, it's more like a sleet ball, with little if any evidence of a mangled snowflake. 

[mappy]

22 minutes ago, Chris78 said:

If the M/D is pinging by mid morning that would be a poor showing from the globals.

 

A changeover before noon would not be ideal, but if I’ve got 6” on the ground by then, then so be it. I’ve been hugging the euro for my backyard. 

[winter_warlock]

8 minutes ago, psuhoffman said:

Wow  shows 5.7 Inches of sleet in southwest Virginia!! That's just insane lol

[yoda]

00z RRFS pounds DC metro between 09z and 13z