OceanStWx

Most guidance has a hint of snow showers for southern VT today, but in reality most models are dogshit when it comes to these shallow upslope snow showers.

Well, it's got a really long runway so you're less likely to slide off it.

Since MLK I've got like 23" It's snowed on 12 of those 21 days.

Me when I get home from work and someone asks me the forecast:

I didn't think so, I was just highlight that a little miss on QPF can be a nice bust on snowfall when the ratios are so high.

True story though, when I measured the snow and told my wife we got 10" she asked "what happened to 1-3?" She said that was our forecast, even though our house was in a winter storm warning. My guess is she was reading the P&C that said accumulations 1-3 inches and missed the Saturday night 4-7 inches.

I ended up being about 0.10" off on QPF for that area. But when you end up with 50% more SLR, you get 4 inches busted on the high side.

9.7 Boothbay, 8.0 Bath

I'm not sure why I don't just draw a hot dog bun shaped edit area over your head every event and nudge those amounts up.

It's been a pretty rough run of snow depth locally since 2018, and local research has definitely shown that we're losing total days with snow cover in the winter. This one definitely has the feeling of the December 2020 storm on the ratio front. That modeled 300 mb deep DGZ was definitely a strong signal for upping SLRs. It's just so damn hard to push yourself to forecast more than 20:1. GYX has at least a 23:1 from the morning observation, so my CoCoRaHS gauge may not have been far off.

I think it's only the second time since 2018 that the flag has been buried. I can't recall being over 15" on the ground all that often. Maybe my memory is still there. I checked CoCoRaHS and I have December 2020 (20"), March 2023 (18"), and today (19") as my only snow depths over 15".

You could just tell from a peek out the window. I could see the individual dendrites sparkling and knew we had ourselves a fluff bomb.

You'll never hurt yourself if you just assume all accumulation stops once the DGZ dries out. If you pick up a weenie half inch, embrace the good fortune, but most of the time that's all she wrote.

10.2" for me. But my CoCoRaHS can overflowed. I could only get 0.35" liquid out of it, but I grabbed a snow core off the board and left it at home to take care of later. The flag marking the snow boards is officially buried too as I'm up to 19" on the ground as well. Never a doubt.

There are a few reasons why I prefer the over on QPF. I'm seeing soundings supportive of around a 15:1 average in the area (200-300 mb deep could support upwards of 20:1 at times). There's a decent crosshair signature around 06z (estimating between PSM and LCI soundings), that's pretty good for 6" snow. The WAA forcing is strong and displaced north of QPF max, which is a red flag that some deterministic guidance may not have things far enough north (which is not uncommon for a high bias on QPF on the equatorward side of systems). The only pause I would have is if there is a messenger shuffle south today. That would introduce a DGZ that is starting to get a bit high in the column for ideal ratios, that's why my totals drop off sharper to the north. I'm not sure I've seen anything significant enough to warrant concerns where I have warnings up.

Let's call it 15:1 average SLR there, that's going less than .33" QPF on the high side, 0.20" on the low side. 71% of the ensemble members are 0.5" or more QPF. Gimme the over.

That's advection from DAW though.

That's how you end up with another kid.

There is a huge slug of 700 mb WAA induced f-gen (NAM slightly farther north than GFS/Euro) so I don't see how there isn't a nice dump somewhere over the southern half of NH.

I believe the HRRR is still using the Thompson microphysics scheme for ptype. So it basically is taking a fraction of snow to all accumulated precip that hour and then looking at surface temp for rain vs freezing rain. In this case, I would guess that there is minimal or no snow, so the ptype kicks it over to liquid and because it's below freezing it spits out FZRA.

It should bang 1"/hr before the DGZ dries out, but I'm always more inclined to go snizzle in the dry slot than FZDZ.

I wonder if that's the HRRR trying to do FZDZ for ptype.

I could buy the double banded look to the jackpots. The HRRR and 12km NAM both kind of have it that way.

I mean to the extent we can, yes. We're briefing partners about more snow and our long range messaging has it, but we won't be doing QPF for that event for a couple days.