OceanStWx

For those interested, here is what goes into the NBM expected snowfall. If you look at the probabilistic NBM guidance, it takes each of these 100 members and puts them in order. The lowest snow amount is the 1st percentile, the highest is the 99th, and so on.

Bryce picking Christmas gifts out of the trees in the front yard?

Beer?

Good news for the Maine Midcoast moose population. Hi-res stuff is hinting at a little instability injection as this thing starts wrapping up around midnight tomorrow night. Theta-e lapse rates are pretty close to negative for several hours, and the DGZ gets to be like 200 mb deep. That's a great sign for high snowfall rates. If the synoptic lift was a little stronger I would be thinking some extreme snow rates would be possible.

I know the day before Bufkit had GYX around 1500 ft of surface warmth but Rumford was more like 900. That's all the difference in the world.

Not really sure it was an aloft thing. The warm layer near the ground was just a little too close to 1500 ft. I like to see it closer to 1000 ft to overcome low level warm air with rates and latent cooling.

Why are you reposting your wedding vows here?

Yes that makes sense, they're using Bourgouin, so if the initial phase was ZR (drizzle most likely) and S there is enough negative area to refreeze the ZR to PL.

Without digging into it, my best guess is perhaps ptype is based on thickness. You could conceivably have thicknesses that are equivalent of having a layer above freezing without actually being above freezing (if they sounding was close enough to 0C over a large enough layer).

My freshmen year we did top 100" but I think 30-35% of that fell on winter break when nobody was around to see it. Just came back to crusty banks and bitter cold. The Finger Lake effect was always fun because a 5 degree wind direction difference meant it was over the Cornell coop site, which was how we verified the forecast contest.

Since technically winter starts tomorrow, I'm running through my fall training on a quiet day. We're actually getting better at providing shorter, hyper-focused training modules rather than the longer, more comprehensive ones of the past. Some good NBM stuff in GYX's assigned training this year. It's a good reminder to myself that any deterministic NBM product is expert weighted (i.e. based on verification). Any probabilistic product is equally weighted, and therefore model biases can affect the forecast. For instance, Kuchera is one of the prominent snow ratios used (as much as 50% in some cases), usually in combination with Cobb and thickness. So certain events with a cold snow, the higher percentiles of the NBM may be biases high thanks to the incorporation of Kuchera ratios.

The day 6 GFS blizzard once it gets to day 2: "Now you see it, now you don't motherfucker"

My wife had a bit of melting too, when the power went out at her parents' and they found out that the propane company had skipped their last delivery and the generator didn't run.

Strongest lift now for NH (arriving shortly in ME) with overlapping 250 mb divergence and 850 convergence. A few hours left to pound I would think before any dry slotting.

I don't know, 4" of the sloppy stuff seems to be the magic number for outages. I would think NH is about to see an uptick shortly.

Got the bird in the oven and the WFO's backup generator in case Ekster hydroplanes into a telephone pole on the way into work.

Crank the oven up to 500 and get that turkey done.

Now it's over some guy named George who owns a bank.

I'm not in love with models closing the 700 mb low so far inland, that's usually a good proxy for the dry slot track. GFS is most aggressive in deepening the mid levels, so that explains why it is so robust on snowfall across the southern edge of the snow gradient.

Easy to find the grid for Winni.

I'm not sure we would be discussing it much at the WFO except for the fact that it will be a high travel day plus all of our partners are going home Wednesday and we effectively lose a day of communication there.

Oh definitely not SNE. I would amend my previous post to say north of the Pike.

Good luck with what? All I'm saying is that it is pretty unique that all the clusters' high end goalposts are decent events. Usually there is a total rat in there. I'm still trying to tease out reasoning, but to me that suggests that timing is more of a factor in producing snow than amplification with this system. Aside from holiday travel aspect, I'm pretty skeptical still.

Interesting system for the cluster analysis. There are definitely clusters (the flatter ones) that have lower mean snowfall, but all of the clusters have a solid 90th percentile event. So even the upper end of the flat members can produce a good low end warning event.