Bob Chill

Flakes falling in rockville but the flames and vapor trails behind them have me concerned

Gfs wont get any credit from many but it appears to have schooled the euro several runs in advance. Nice run. One more shift and DC will be happy.

Likely. 540 thickness is just north of the m/d. 546 would likely be the r/s line. Cold air and slp in good spots

I can extrapolate from here

I'm interested. Fast moving progressive patterns suck for long lead tracking so analyzing every 6 hours is a waste of time. I thought everyone wrote this off already though?

Rock solid event today. Over 5" snow, heavy rates for a couple hours, daytime snow, instant stickage, thundersnow/sleet for a few lucky folks, complete road coverage, sleet and zr topper, minimal rain after snow tapered off and my yard exceeded climo... Helluva lot to like right there!

Last hurrah band is bad ass. 5" with compaction from sleet earlier. Great event.

Yep, climo+ year in the books. Best worst winter ever.

4.1" Rockville. Might top 5" before sleet. Going to be close...

No doubt in my mind. At least for my yard. 3"+ in under 3 hours is impressive with any storm around here.

3" as of 8:40 in NE Rockville. Best thump since Jan 2016.

Euro already busted

The only thing you need to worry about is the flip to sleet timing. Stop trying to extrapolate something that isn't going to happen.

You're worried about the wrong thing. Lift is oriented W-E as is the moisture flow. Look to your west and not south.

What's better than 1 MoCo deathband before 9am? Answer: 2 deathbands before 9am Should top 2" here shortly

Radar hallucinations have begun early it seems. The dynamics and lift are overhead and will remain there until well after a flip to sleet and zr. Enjoy the snow while it lasts and stop worrying about things that shouldn't be worried about in the dc/balt/burbs areas.

Straight dumping in Rockville. Close to or over 1" already.

Euro is the dryest model through 18z tomorrow. .2-.4qpf until you get west of the blue ridge.

This storm should also put us both above climo. This has been the most disastrous climo+ year in history though.

You'll like the ukie. Gfs/ukie blend is money

After double checking all the differential equations on the gfs through hr18 I've comfirmed that the 0z run is dead balls accurate.

Sub freezing at 31 now. Nice to have a multi hour stretch sub freezing before onset. Can make a big difference if rates are light at the beginning. Also, stop looking at the hrrr until precip is overhead or at least close. It uses radar data at initialization and generally does really bad or is very inconsistent when onset is still a number of hours away. Honestly, I've never found the hrrr that useful with winter storms. Globals do far better in general.

Radar looks solid but there is no way all the guidance is wrong about when meaninful precip breaks out over each of our yards. Even if onset ends up being 3 hours early or whatever it won't change the outcome for many. The good lift/frontogen is likely very well modeled. Even if onset comes early it will prob be inconsequential until things get more dynamic later overnight for you and around dawn for my yard. This will be a fun event. Sleet is more disruptive on the roads than snowfall. An inch or 2 of frozen ball bearing on the roads can wreak havoc worse than snowfall.

Storm thread was excellent. I was always catching up and wasn't watching daytime model runs until well after they ran. Enjoyed the clean/concise rundown. I applaud the sub posters and mods keeping things clean, concise, and very readable. The one thing I want to add that I don't think was discussed much last few days are ratios. Yes, we have a really nice column at onset but it changes very quickly in regards to DSG and what type of snow will be falling. This won't be pretty fluffy dendrites and even with all snow falling (prob heavy at times) it will resemble sand and oatmeal falling at times. There is a sig WAA pump going on up above 850mb. Losing 800-700mb levels while everything below is important to understand. Could be all snow but still only 8:1 (or lower) ratios. If anyone remembers Feb 2014 or March 2013 onset it will likely resemble that type of snowfall. Not pretty 10 or 12:1 stuff. More of a pounding white meteor or sand or oatmeal or whatever you want to call it. Snow will be dense and will go through a progression of worsening ratios until sleet takes over.

34 and ready for my fully stocked winter wx buffet Just to clear the air and not derail this thread... I took a break for 2 reasons. 1) was burned out and not enjoying myself at all around here and 2) have some important stuff (all good) going on in my personal life. I said I'd be back for obs and here I am. Let's do this man.