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

[bncho]

1 minute ago, high risk said:

              You are spot on.   MPAS is going to replace FV3 in RRFS Version 2, and it will probably be used across the board eventually in the NWS models.

Will this greatly improve the verification scores of the American models? Will the GFS be an actual model to consider once this new core is implemented?

[WEATHER53]

21 minutes ago, Snowciopathic Snow Bro said:

ZR reduction/deletion, ftw!  Trees, you can stop exploding or falling down now.

And north and west of 95 is how many miles?

[Snowciopathic Snow Bro]

2 minutes ago, WEATHER53 said:

And north and west of 95 is how many miles?

As many miles as NWS needs to verify their discussion.  Might be Pittsburgh for all we know.  Let us embrace the ground truth when it's time to do so.

[jayyy]

I’m going with 10”. If I hit that in combined snow and sleet up this way…. I’m happy. Lotta tracking to settle for 6”. I’ll be frustrated for sure if I end up with 6 and my parents in NY end up with 18

[Scarlet Pimpernel]

Interestingly, in their latest forecast package, LWX has actually upped the amounts a tad for the immediate DC suburbs in MD (Bethesda, Silver Spring, etc.) in tonight's snow as well as snow/sleet tomorrow.

[mitchnick]

10 minutes ago, Weather Will said:

WB 18Z ICON snowfall is an improvement.

Kuchera better and makes sense with higher ratios to start. 

[Scarlet Pimpernel]

4 minutes ago, WEATHER53 said:

And north and west of 95 is how many miles?

I take that to mean north and west of the main urban corridor around DC-Balt.  So north and west of suburban DC for instance, somewhere well enough outside the Beltway.

[LordBaltimore]

11 minutes ago, high risk said:

              You are spot on.   MPAS is going to replace FV3 in RRFS Version 2, and it will probably be used across the board eventually in the NWS models.

I had no idea it was even an option for the GFS. That's awesome if it happens

[konksw]

3 minutes ago, Scarlet Pimpernel said:

Interestingly, in their latest forecast package, LWX has actually upped the amounts a tad for the immediate DC suburbs in MD (Bethesda, Silver Spring, etc.) in tonight's snow as well as snow/sleet tomorrow.

I’ll take it. 

[jayyy]

I’ll take it. 

Respectable. The MoCo-HoCo area to me is the biggest ? mark going into this thing. Transition zone of >50% snow will be right there. Could see 6, could see 10-12. A few hours will make all the difference

[stormtracker]

40 minutes ago, high risk said:

        It's pretty clear that the NAM is slow with the leading edge of the precip.    It definitely has a bias of being too slow to advance precipitation into very dry air.     The 18Z cycle doesn't bring snow into DC until 6Z, and I doubt it will take that long.   It's probably good reason to ignore its QPF for the front end thump and go with wetter models.    That said, none of that means that it must be off with the timing of the transition to sleet.    It might very well be too fast with that, but I wouldn't base that off of not getting snow to the ground quickly enough at the leading edge.

I've mostly accepted the transition time.  It's the thump QPF I was worried about.  Feel a little better about this after your reply.

[jayyy]

All snow 12-18” with 24” lollipops - the WSW for where I grew up. Still have time to make the drive up. Off until Wednesday. It’s very tempting. But if I can manage a foot here, I’d def rather just watch it from MBY

[Scarlet Pimpernel]

5 minutes ago, stormtracker said:

I've mostly accepted the transition time.  It's the thump QPF I was worried about.  Feel a little better about this after your reply.

Same.  I don't necessarily question the NAM's thermals per se for the most part (though I have a sense it's perhaps too aggressive on that).  But it is clearly on the really light end in terms of QPF up to the point where most flip to sleet.  Nearly every other model has a good, solid thump of snow into at least mid-morning or so tomorrow.  Given LWX's latest forecast, I can only assume they view the NAM's QPF as a low outlier as well.  We will see.

[Maestrobjwa]

Just now, Scarlet Pimpernel said:

Same.  I don't necessarily question the NAM's thermals per se for the most part (though I have a sense it's too aggressive on that).  But it is clearly on the really light end in terms of QPF up to the point where most flip to sleet.  Nearly every other model has a good, solid thump of snow into at least mid-morning or so tomorrow.  Given LWX's latest forecast, I can only assume they view the NAM's QPF as a low outlier as well.  We will see.

Yeah of all the issues we've battled with this moisture has never been one of them...and the NAMs when they aren't going crazy with moisture they're dry sometimes, lol

[Maestrobjwa]

4 minutes ago, jayyy said:

All snow 12-18” with 24” lollipops - the WSW for where I grew up. Still have time to make the drive up. Off until Wednesday. It’s very tempting. But if I can manage a foot here, I’d def rather just watch it from MBY

Where is that?

[Scarlet Pimpernel]

Just now, Maestrobjwa said:

Yeah of all the issues we've battled with this moisture has never been one of them...and the NAMs when they aren't going crazy with moisture they're dry sometimes, lol

Leaving aside whether or not the NAM is too aggressive with slamming that mid-level warmth in too fast (and too much)...I really wonder why it is so anemic with the QPF surge.  I mean, it seems like it has generally the same overall synoptic setup and progression as most other models, I believe?

[SnowBeach]

First flakes falling here at Wintergreen Resort. 

[Maestrobjwa]

2 minutes ago, Scarlet Pimpernel said:

Leaving aside whether or not the NAM is too aggressive with slamming that mid-level warmth in too fast (and too much)...I really wonder why it is so anemic with the QPF surge.  I mean, it seems like it has generally the same overall synoptic setup and progression as most other models, I believe?

According to more knowledgeable folks in here...it appears so. So given that--that's another reason to be skeptical of the QPF. Nowcasting may bear that out...

[stormtracker]

Don't know if it's reaching the ground, but there's a good slug of precip just NW of RIC

https://weather.cod.edu/satrad/nexrad/?parms=LWX-N0B-1-24-100-usa-rad

[jayyy]

Where is that?

Orange County NY

[stormtracker]

GFS has begun...I'll just post relevant panels as I get them

[BTRWx's Thanks Giving]

Fwiw, the 20z hrrr converts .4-.5" qpf to 6-7" snow at the end of its range. 

[CavalierHoo]

2 minutes ago, stormtracker said:

Don't know if it's reaching the ground, but there's a good slug of precip just NW of RIC

https://weather.cod.edu/satrad/nexrad/?parms=LWX-N0B-1-24-100-usa-rad

Can confirm very light flurries in Richmond and just south.  Multiple reports now.

[stormtracker]

[stormtracker]

Kinda hoping we hang on here

[LongRanger]

I imagine the QPF vs snow depth measurements are going to be distorted by IP. Whatever fluffy stuff falls first is going to be compacted by sleet on top.

[stormtracker]

Sleet kingdom from here on out

 

[BTRWx's Thanks Giving]

Just now, LongRanger said:

I imagine the QPF vs snow depth measurements are going to be distorted by IP. Whatever fluffy stuff falls first is going to be compacted by sleet on top.

The hrrr maps I shared were all snow. 

[stormtracker]

[stormtracker]

Well...good bit of QPF I guess