OceanStWx

3rd time my almost 5 year old has seen a snow depth over double digits. But it is awfully wintry up here. Had 8.1" as I left for work and will probably bag another 1-2" before it's over.

Yeah, long term climo is like 11:1 for our area, 13:1 in the mountains.

Even the NAM has the little afternoon peak of snowfall. It's a saturated sounding with lift in the DGZ. Could be a nice little topper. 18z NAM squeezes out another cheap 3 inches for PWM.

Trying to align more with climo rather than CWA. Our mountains/foothills just get more snow, so we bumped criteria up to 8. Otherwise everybody stayed at 6. This was NWS wide, so you'll see things like the east slope of the Berks bumped to 7.

Well you also have new warning criteria this season (8"). So no watch because while you may push 6" I'm comfortably below the 8" threshold.

I think so. These usually come in a little faster and I'm about 10 pm with this forecast.

I actually like the purple area for some paste and Forecast soundings are hovering near wetbulb freezing and once we get over 4 inches power outages usually spike.

Which means congrats Dendrite.

If you toggle between that and Kuchie you can see the Essex Co has a lot of mixed contamination there.

The NAM even gets max wetbulbs down to 0 to Long Island Sound Thursday. The problem is they rocket up to +1/+2 as the precip starts. Wetbulb 0 hangs out right around Route 2.

Yeah, it's looking like we'll get max wetbulbs down around -2C through NH during the day Thursday. I'm less worried about too much rain in southern NH, more worried about the airmass being too marginal to really stack up the snow if things are partially or close to melting.

That's a little bit of an artifact of how we do QPF (and thus snow amount). We only have 72 hours of QPF, so last night's forecast would've cut off part of the event. Now with it included today it looks like we increased amounts, but it's just adding the end of the event.

Wait, I thought the Euro was a terrible now.

We can start high and adjust higher as needed.

It's like whenever we update software around here and it blows away some local fix we had. It's almost like the GFS was updated and they forgot to carry over the code that fixed this.

I would be more gung ho if forcing weren't kind of going through the meat grinder as it squeezes east southeast. If we're losing the punch behind the WAA, rates will be lower, and accumulation in a marginal environment could struggle. If it was a wall of WAA like a typical SWFE I would be on board for more widespread warning. Right now I'm leaning low end as you say.

Much warmer lower levels on the GFS vs NAM for instance (what else is new). GFS mid to even upper 30s over southern NH, vs NAM 32.

If you can find a snow depth change map that can be a more realistic representation of what falls when it's mixy. WeatherBell has it for the NAM, GFS, and Euro. All show a 10 inch increase in the max swath (which coincidentally is my favorite number to cap SWFEs at). This is a bit of a hybrid system though, as the dry slot looks like it never punches all the way northeast. But the Euro has the swath from RUT to DAW, GFS a little north, NAM closer to the MA border.

Timing could be better. Don't need precip barreling in during the warmest part of the day Thursday.

I do like the overall ensembled H5 look though. Confluence over the Crown of Maine at least supports the cold surface temps.

I think that's the one.

The only one that really jumps out at me with 0.5" radial on just in-situ cold air was the late 90s that started below zero but ended up 50s and thunder later in the afternoon.

There are really two ways I like to think of it, active or passive (in-situ) CAD. Active you either can get a backdoor of sorts to drive the cold south along the terrain, or the pressure gradient is oriented just so as to produce that barrier jet that holds the cold in place. In-situ CAD you wet bulb down below freezing thanks to a dry air mass and the cold just takes a long time to scour out, but eventually does because there is no barrier jet.

Forget making a snowman, my son's favorite thing to do is shovel the snow.

The most difficult thing about forecasting ice is that it's such a narrow variable space to maintain that as the dominant ptype. I typically lean heavy on sleet because of that. The problem I'm having with some of the forecasts I'm seeing is like for BGR: Roughly over the rest of the event there a forecast of 1 inch snow, 1 inch sleet, and 0.33 inches ice - off 1 inch QPF. If you take conservative ratios of 2:1 sleet, 10:1 snow, and 0.7:1 FZRA, that's already over 1" QPF. I just don't think there's enough QPF for all these things to happen, either sleet robs from FZRA or vice versa.