Just got back from poker night and got caught up and I'm pretty happy with the 0Z models. Would love for the GFS or AIFS/AIGFS to be right and give most of CNJ and the 95 corridor from Philly to NYC and the coast and my house almost all snow with very little sleet/ZR, like the NBM is showing with 12-18" of snow for everyone, but we've seen too many times when the WAA is undermodeled and with most other models showing 25-40% of the QPF (liquid precip basis) falling as sleet, mostly, with a bit of freezing rain (ZR) it seems quite possible most of our area could get about 33% as sleet/ZR. Here's some thoughts for how to look at that given that I still think mets need to find a way to report total frozen mass in mixed precip events as frozen mass is much better correlated to impacts than simple depth.
If we take the rough average of QPF across the models, which range from 0.9-1.5" for CNJ, that's 1.2" as QPF and if we assume 66% of it is snow, that's 0.8" QPF as snow and 0.4" QPF as sleet/ZR, so let's say that's 0.3" as sleet and 0.1" as ZR. At 13:1 snow:liquid ratio (the rough ratio seen on the NBM through 7 pm Monday when many models switch to sleet), the 0.8" QPF as snow is 10.4" of 13:1 snow, the 0.3" of QPF as sleet is 0.9" of sleet for a total depth of 11.3" and the 0.1" of QPF as ZR has no depth as it's just absorbed into the snow/sleet pack although some compaction and freezing will occur, especially near the top.
Bottom line this could end up having 10" of depth after compaction containing 1.2" of QPF which has a top several inches being frozen solid with surface temps in the mid/upper 20s. This is a friggin' mess to drive in, walk on, plow, shovel, etc., and likely worse than dealing with that same 1.2" QPF of frozen mass as pure 15:1 snow or 18" of depth. Won't be nearly as pretty as pure snow (and I love pretty snow), but will be as or more impactful. And if there's more like 50% of the 1.2" QPF as snow (7.8" at 13:1) and 50% of the QPF as sleet and no ZR (2" of sleet at 3:1), that's 9.8" of depth and keep in mind that sleet melts much more slowly than snow as it has a far lower exposed surface area per unit volume. But many will look at the NWS forecasts of 12-16" of snow and look at the 10" of snow/sleet/ZR on their lawns and call the forecast a bust, when in reality both are similarly impactful
Anyway this is a long path to my posting DT/WxRisk's first guess map, as I think it's the best one I've seen and I'd say I'm very aligned with it, as it has most of CNJ and 95 from Philly to NYC in the 8-12" of snow swath and noting that much of that area would also be receiving sleet; he doesn't specify how much sleet, but it's part of the 8-12" of "snow" and could very well be like my example above of ~11.3" of snow/sleet depth, compacting to ~10" after ZR, containing 1.2" QPF (7.8" of 13:1 snow + 2" of 3:1 sleet and 0.1" of ZR). I also like his 12-18" area with no sleet beginning around 78, which is a good guess. I might have his light blue area with a changeover to sleet/ZR all the way up to 78, though.
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