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

[NorthArlington101]

[weathercoins]

Would not worry about how the NAM is handling complex energy interaction, and specifically the thermal profiles, past 36 hours.  If it showed something amazing the responsible thing to do would be to disregard it; don’t think it’s different when it shows something like this, especially if inconsistent with the beginning of the run 

[Negnao]

Man if you just read the hyperbole here about the nam “improvements” and didn’t look at the run you would have thought it spit out the blizzard of 93. 

[psuhoffman]

Hopefully the RRFS sucks

[DDweatherman]

Just now, Negnao said:

Man if you just read the hyperbole here about the nam “improvements” and didn’t look at the run you would have thought it spit out the blizzard of 93. 

It always starts that way and losses to end that way too…. But let’s hope it’s doing NAM things…could be post truncation and outside the best range.

 

Just now, psuhoffman said:

Hopefully the RRFS sucks

We were hoping it was good 2 hours ago. Most of these mesos do in fact suck, and AND they’re at range. 

[NorthArlington101]

2 minutes ago, psuhoffman said:

Hopefully the RRFS sucks

It's better than the NAM? At this point I lock this in 100% with no thought

if you mean the mostly FRZA as opposed to sleet though, I agree

[psuhoffman]

6 minutes ago, MN Transplant said:

We took a step backwards with a stronger (the strongest yet) 850 low in Ohio.

NAMs don't bother me, the jump around run to run like crazy...but what do you know about the RRFS because it looked great at 12z and just want WAY WAY north... I don't know enough about it to know whether that should bother us or not 

[Ji]

It's better than the NAM? At this point I lock this in 100% with no thought

if you mean the mostly FRZA as opposed to sleet though, I agree

As long as I get any color not in blue. I’m good.

[NorthArlington101]

2 minutes ago, psuhoffman said:

NAMs don't bother me, the jump around run to run like crazy...but what do you know about the RRFS because it looked great at 12z and just want WAY WAY north... I don't know enough about it to know whether that should bother us or not 

This is kinda noise level to me but might be IMBY bias - re: your post below, fair enough.

[psuhoffman]

1 minute ago, NorthArlington101 said:

It's better than the NAM? At this point I lock this in 100% with no thought

problem is that's it...the warm layer has blasted all the way into PA by then...so pretty much we all end up with 6-7" which is fine for DC but for places NW of 95 it took away 6" of snow from the last run that had 10-12" in places 

[Ji]

NAMs don't bother me, the jump around run to run like crazy...but what do you know about the RRFS because it looked great at 12z and just want WAY WAY north... I don't know enough about it to know whether that should bother us or not 

I’ve used that model a couple times so my first thought was this is no way ready for the big leagues


It needs to go back to AA ball for a year

[DDweatherman]

Just now, psuhoffman said:

problem is that's it...the warm layer has blasted all the way into PA by then...so pretty much we all end up with 6-7" which is fine for DC but for places NW of 95 it took away 6" of snow from the last run that had 10-12" in places 

We made great progress at 12z and I liked the nams through 36. Let’s see what the jv models have vs the middle school model set. 

[MillvilleWx]

1 minute ago, psuhoffman said:

problem is that's it...the warm layer has blasted all the way into PA by then...so pretty much we all end up with 6-7" which is fine for DC but for places NW of 95 it took away 6" of snow from the last run that had 10-12" in places 

I still have 10-12” for the northwest crew using the internal snow ratio calculation the RRFS uses if it’s any consolation. The crazy thing was how far the warm nose blasted in PA. That was wild. Freezing rain all the way past the turnpike 

[psuhoffman]

1 minute ago, MillvilleWx said:

I still have 10-12” for the northwest crew using the internal snow ratio calculation the RRFS uses if it’s any consolation. The crazy thing was how far the warm nose blasted in PA. That was wild. Freezing rain all the way past the turnpike 

wow what did it show 12z for this area then because it cut our snow in half on the publicly available maps lol 

[DDweatherman]

1 minute ago, MillvilleWx said:

I still have 10-12” for the northwest crew using the internal snow ratio calculation the RRFS uses if it’s any consolation. The crazy thing was how far the warm nose blasted in PA. That was wild. Freezing rain all the way past the turnpike 

Just when we thought the models were picking up the impression of the high pressure and the damming. 

[DDweatherman]

Just now, psuhoffman said:

wow what did it show 12z for this area then because it cut our snow in half on the publicly available maps lol 

Yes, I saw it was 12-14 over us at 12z 

[SomeguyfromTakomaPark]

2 minutes ago, MillvilleWx said:

I still have 10-12” for the northwest crew using the internal snow ratio calculation the RRFS uses if it’s any consolation. The crazy thing was how far the warm nose blasted in PA. That was wild. Freezing rain all the way past the turnpike 

Freezing rain would be a real problem here given the low temps and high qpf.  

[Terpeast]

3 minutes ago, MillvilleWx said:

I still have 10-12” for the northwest crew using the internal snow ratio calculation the RRFS uses if it’s any consolation. The crazy thing was how far the warm nose blasted in PA. That was wild. Freezing rain all the way past the turnpike 

Unless the synoptics changed drastically, I don't think the freezing rain in the PA turnpike is right. The arctic high is already stronger than had been modeled (1050) and the cold air both at surface and aloft isn't going to go that easily. I can see a flip up to the M/D line by early afternoon, but probably not much further north than that given recent trends.

[psuhoffman]

1 minute ago, DDweatherman said:

Just when we thought the models were picking up the impression of the high pressure and the damming. 

These 18z runs continued that trend...that wasn't the issue...the problem was around hour 36 they go berserk with the primary to our west and amp the system like crazy.  A little better high and damming won't offset that.  That's like throwing a couple poker chips on one side of the scale and then dropping a piano on the other.  

[baltosquid]

1 minute ago, psuhoffman said:

wow what did it show 12z for this area then because it cut our snow in half on the publicly available maps lol 

[Ji]

Stefi Graf model

[87storms]

21 minutes ago, SnowenOutThere said:

I mean it has the FGEN but only bothers to bring it north after we all are sleeting. The HRRR has FGEN more spread out which makes sense imo with this setup and then its real band is right on the snow/sleet line

Yea I noticed that on recent runs…you can basically follow the lobe of energy from the Baja low and that’s the driving force behind the potential changeover. WV loop is gonna blossom on Sunday once that piece gets near…just gotta see whether it’s too much of a good thing.

[MillvilleWx]

2 minutes ago, psuhoffman said:

wow what did it show 12z for this area then because it cut our snow in half on the publicly available maps lol 

Lost about 4 inches, but legit everyone lost 4-6” from that run until you got north of I-78 where they gained 4-6”. It was because of the 7H and 85H evolution. Just waaaaay too aggressive for here and the warm nose would catapult its way north. Provided a trend graphic below. It’s been bouncing around like that rubber playground ball we used to use. Still trying to figure itself out, so wouldn’t sweat it. I loved the run up until 18z, then it went agro. 

2 minutes ago, DDweatherman said:

Just when we thought the models were picking up the impression of the high pressure and the damming. 

The synoptic evolution would cancel that. Surface remains cold af though. It was actually a worse case scenario regarding impact. That would be hell around here and travel would hit an impasse. 
 

[psuhoffman]

8 minutes ago, Terpeast said:

Unless the synoptics changed drastically, I don't think the freezing rain in the PA turnpike is right. The arctic high is already stronger than had been modeled (1050) and the cold air both at surface and aloft isn't going to go that easily. I can see a flip up to the M/D line by early afternoon, but probably not much further north than that given recent trends.

[Ruin]

20 minutes ago, NorthArlington101 said:

Sleet way over done warm bias om model. Fresh artic air strong high 

[Ruin]

Just now, psuhoffman said:

What i keep saying strong artic high its like models and forecasters are ignoring it

[baltosquid]

ICON looks prepared to amp more at hr36

[Scarlet Pimpernel]

Interesting snippet from LWX's latest AFD.  I bolded the part that stood out to me, involving heavy sleet at times and possibly "a few inches" of sleet accumulation!  If that happens...wow...that would be an unreal sleet bomb, bigger than what I got in Feb. 2007 (and this will be a LOT colder too).  They've adjusted the Saturday night and Sunday accumulations of snow/sleet a bit but still generally in the same range as before at least for the DC metro.

 

While this event will start as a period of heavy snow
(potentially 1-2"/hr at times) overnight Saturday into early
Sunday morning, a potent warm nose aloft will quickly transition
most locales to sleet by mid-morning. Now, this will be very
heavy sleet at times, especially before the afternoon, so even
the sleet accumulations could amount to a few inches. Hence, the
storm total snow forecast you will see on weather.gov/lwx/winter
will be showing the combination of snow and sleet.

[Terpeast]

2 minutes ago, psuhoffman said:

That big of a change in one run, outside of range? Toss until other models say otherwise. 

[SnowenOutThere]

4 minutes ago, psuhoffman said:

I think we should feel better knowing this was a synoptic scale shift instead of a thermal driven one. Less likely it seems for a dynamics model to beat out the Euro and Gfs on the large scale picture.