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

[bncho]

1 minute ago, Weather Will said:

WB 12Z HRRR snow breaking out 2am Sunday 

Okay I think HRRR is an hour faster with more precip. 

Edit: no, it's just more precip

[aldie 22]

8 minutes ago, Ji said:

Feb 2015?

Maybe..i was still in leesburg then...this cold can't be that damn easy to bully even at upper levels. I do think the storm im thinking of the low was pretty far west so the cold held on longer at all levels...I don't know i just think getting that much sleet feels a bit over the top

[pazzo83]

low of 8.6F here, DCA at 10F.  Dewpoint got down to -13F (almost certainly the lowest since I've lived here).  Right now 10/-11.,  Going to take a while to saturate that column lol

[Weather Will]

6am moderate/ heavy snow DC WB 12Z HRRR

[Interstate]

38 minutes ago, Eskimo Joe said:

It's cold folks

 

Yep. And even know we had two above freezing days. The ground is still frozen solid. 

[Weather Will]

7am still a beat down DC WB 12Z HRRR

[Solution Man]

Just now, Weather Will said:

7 am still a beat down DC

Will bringing the heat this morning!

[SnowenOutThere]

1 minute ago, Weather Will said:

7 am still a beat down DC

Looks to be maybe an hour or so faster moving the mix line north so far, though its also wetter. 

[SomeguyfromTakomaPark]

1 minute ago, Weather Will said:

7am still a beat down DC WB 12Z HRRR

Oh this is looking like a proper thump. 

[Weather Will]

8am another hour of heavy snow DC

[bncho]

Will, we do PBP, not frame by frame 

[SnowenOutThere]

Wait does anyone know why on the past runs the HRRR continues to accumulate snow past the mixing line moving north? Does it see it as a snow/sleet mix or as the ratio for sleet? I don't think any other model includes sleet calculations with their snowfall output so that seems weird. 

[bncho]

Just now, SnowenOutThere said:

Wait does anyone know why on the past runs the HRRR continues to accumulate snow past the mixing line moving north? Does it see it as a snow/sleet mix or as the ratio for sleet? I don't think any other model includes sleet calculations with their snowfall output so that seems weird. 

Maybe sleet/snow mix?

[MN Transplant]

I'm not sure that I'd completely characterize it as a "thump", given that the HRRR is 0.05" QPF per hour from 09z to 14z, but if we do score favorable ratios it'll be a nice period.

[Eskimo Joe]

More sleet than ZR on the HRRR

[Weather Will]

9am still heavy snow DC with sleet knocking at door.

[SnowenOutThere]

Just now, bncho said:

Maybe sleet/snow mix?

It must be as weatherbell shows both sleet and snow accumulating for me during the mid-late morning. 

[MN Transplant]

DC loses the column between 14-15z, just shy of 0.5" QPF.  So, the HRRR is probably a 5-7" event before the sleet.

[LP08]

Just now, MN Transplant said:

I'm not sure that I'd completely characterize it as a "thump", given that the HRRR is 0.05" QPF per hour from 09z to 14z, but if we do score favorable ratios it'll be a nice period.

Has that weird dry spot almost all over Northern Va and MD compared to 6z. Surrounded by heavier stuff in all directions.  Strange run but possible

[bncho]

Less thumpy on the HRRR

[Interstate]

Highs in the mid to upper 20s on Sunday and Monday should really help road crews out. I thought we were in big trouble when the temps were supposed to be in the teens. 

[SoCoWx]

Obviously I don't buy what the Euro is selling on the freezing rain, that being said, it appears as though freezing rain chances are increasing. I see it on the GFS and HRRR for sure. Not great.

This makes me wonder then, why the NWS actually ticked down the ice amounts for Richmond this morning? Their local office down here reduced the forecasted freezing rain amounts to between a quarter and a half inch.

That much would still be crippling, but not as deadly and destructive as nearly an inch (or more) like the Euro keeps saying.


.

[AACOUNTYMD]

When does the HRRR get all precipitation out of DC/BWI/Baltimore area?

[Terpeast]

11 minutes ago, WeatherShak said:

Yes- Ji is right below. In my 15 years in Washington, we’re good at busting low, but in unique/complex setups (like now) we have busted high a few times.

We’ve busted low recently because the temps had been too warm at the surface - is the main reason. But that’s not the case now. 

[MN Transplant]

The 06z HRRR was able to "beat back" the mix line in the late morning period.  It doesn't happen on this run, and it is more NAM-like in flying the mix line north.  Not nearly as bad as the NAM though.

[baltosquid]

HRRR started a bit wetter it looked like but got drier as things went on. Probably part of why it lost thermals faster too.

Edit: this kind of is where my thinking is now - barring a surprise evolution, we just need prodigious rates to hold off the mix line as long as possible. Bully the warm nose for an extra hour or two and we boom. Fail to do so and we flip in the mid morning and end up on the low side.

[Weather Will]

HRRR is drier this run compared to 6Z. WB 12Z HRRR 4pm Sunday.  I guess a new way to fail is to be dry slotted as the coastal transfer takes place.

[Solution Man]

Little dated but the latest

[Solution Man]

1 minute ago, Weather Will said:

HRRR is drier this run compared to 6Z. WB 12Z HRRR 4pm Sunday.  I guess a new way to fail is to be dry slotted.

We do dry slots better than anybody 

[TSSN+]

1 minute ago, Weather Will said:

HRRR is drier this run compared to 6Z. WB 12Z HRRR 4pm Sunday.  I guess a new way to fail is to be dry slotted as the coastal transfer takes place.

HRRR changes every run with qpf placement it will be different at 18Z