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storm cancelled

1.6"@15:1 would do it on the coast... Sent from my SM-S166V using Tapatalk

The only frustrating part of this storm will be onset watching Virga until it moistens up.

Hey there--resident tropical weenie here. Recon can incredibly useful, as it provides hard observations for areas that may not be sampled as well as they would be over the U.S., which in turn makes the initial conditions the models rely on to make their projections more accurate. So here, since they're sampling that Baja energy, it'll probably aid in more precisely projecting its intensity and speed. We're so close to the event that I doubt it makes a huge difference, but it just closes off one of the unknowns. Hope that helps.

In 1994 we had a devastating ice storm with 2 inches of solid ice. At times, we had moderate rain and 18 degrees! It was due to the cold layer being shallow enough for the rain to reach the ground as liquid despite such low surface temps. I this upcoming storm, hopefully the cold layer is thick enough to freeze the raindrops into sleet!

that's a great thing Euro AI is a good model probably the best i stand by it but maybe we're just going to get some sleet. But a 30 mile shift south could change the outcome to all snow. still another 72 hours until the first flakes come in. Plenty of time for that southern 30-40 mile shift!

From Blacksburg NWS Now for what everyone really cares about: snow and ice totals. Due to the cold air in place and already cold ground temperatures, any snow that does fall will be light and fluffy and accumulate quickly. The initial onset of snow will cause 2-4" of snow to fall along/south of the NC/VA border, increasing to 5-8" along US-460. Northern areas along I-64 will see 10-14"+ of snow, with locally higher amounts possible. On top of the snow will be sleet accumulations, possibly measured in inches as well. Around 1-3" of sleet could accumulate due to the very cold surface temperatures on top of the snow. If the sleet starts sooner, the snow totals will also decrease. Finally, ice accumulations will be light along/west of the Blue Ridge and north of I-64, with anywhere from a glaze to two tenths possible. For the Piedmont, 0.25-0.40" is expected, mainly Sunday afternoon/evening. The ice will add a crusty hard layer on top of the snow/sleet. With all of the above being said, take this storm seriously and prepare now. Due to the storm having mixed precipitation types, roads will be harder to clear, causing travel to be difficult and dangerous. If at all possible, avoid travel unless absolutely necessary. With the slightly later timing of the storm, Monday morning`s commute will be treacherous, especially with very cold temperatures keeping all fallen precipitation from melting.

The issue with Kuchera isn't necessarily the math but rather model output, so the maps themselves are often flawed. Ground truth is typically less, but that doesn't mean they are always wrong, of course. Snow calculation is complex, as is my explanation here (apologies). The actual equation for Kuchera is this: But nearly none of the output products in models take into account the other variables of snow growth. Lift, dendrite growth, and humidity, for example. Snowfall rates are never constant over X time. As a basic tenet, highest snowfall ratios (say 25:1) occur when most of the lift is situated at temps in the atmosphere between -12 and -18 Celcius. Otherwise known as the "snow production zone." There's a method (Cobb) that uses a layered approach to estimate snowfall ratios at a given time. It can be paired with Bufkit data to estimate total snowfall, because the Bufkit software has the highest vertical resolution to pair with soundings. Using this with the 6Z GFS run, for example, gives us 13.2" of snow on 1.04" of precip at AGC. Ratios vary from 5:1 up to 30:1 in hour snapshots. That's a higher-end result when compared with the averaged NBM data (0.79" precip average). Same method is 9.6" of snow on the 0Z GFS run. We can run this on the NAM, too, but it's not yet within range. My main point is that, looking at the 6Z Euro for instance, if people start expecting 17" they are quite likely to end up disappointed, so I had wanted to put out a general caveat emptor for those reading the maps that maybe aren't aware of the limitations.

How much of an ice impact do we see now for the central and southern valley. Does anyone else not believe those surface temps get that high? .

Yeah, yeah, man, it's cool. I'm not real hip on the evolution so thanks. I looked over some of the stuff that blizzard posted last night and it looks like it might have been throwing back some snow at us,so I guess that kind of image and wish is stuck in my head. And yeah, I realize if it's not tucked i'm not quite in the right spot for death banding..

HHHR up to bat .

Those maps can only ever go out 72 hours.

"In house" models seem to always have been a hype/marketing tool more than anything anyway.

I have seen several maps showing over 10” for KILN, felt that the totals were overdone. I may have been wrong in that assessment.

The red taggers are getting snarky. I like it! So humbling.

I was wondering about this too and haven't seen it discussed much. The models all give a wind output, you can check them. For example this panel shows wind *gusts* above the surface when the low is forming off the coast sunday evening. Pretty breezy, but IDK if this would verify blizzard in the metros. Worse to the east.

The mix never made it to the CT shore in 2013.

This type of system is not gonna produce 2’ in a broad area. You want to see the coastal take over and slow to even entertain it.

Ukie Ensembles. Not bad

They don’t have the precipitation type and rate for the ECMWF-AIFS like they do for the other models on Pivitol.

3.5 inches. Condo Association is plowing. Ony do that if they measure 3+. Surprised when I got up.

When will the main thread be locked down to storm mode? I learn a lot reading on here but it’s difficult scrolling through meaningless posts. .

sounds about right....i'm hoping my mulch doesn't warm up too much

Depends if the models can stop themselves from laughing hysterically at the absurdity of someone calling the Gulf of Mexico the "Gulf of America." If they can avoid frying their circuits from uncontrollable giggling, the resulting model outputs should become more accurate. (ETA: sorry, Mappy - didn't see your post until after I posted this. But...come on, lol)

I mean nothing supports 2’ really. I’d want to see like at least 1.7” QPF modeled in a broad area to entertain its