Kuchera adjusted for ratios
Snowing in AC and even a bit north of there now - moving in faster than expected. - anywhere you see the green (above 20 DBZ) it's snow reaching the ground; the blue could still be virga (snow that is falling which the radar "sees" but which evaporates before it reaches the ground - this is because the column is not saturated with moisture yet (often well below 100% RH).
Since I live literally maybe 3/4 of a mile from the Turnpike and am very close to his 6" line (a few miles west of it, as his line is a few miles east of the TPK in my area). I predicted 5.5" for me earlier today on 33andrain. Seems like a decent guess and oddly enough, that's exactly what the NWS graphics page spits out for Metuchen for the storm. I still think the upside is more than the downside with this storm though, given the high ratios and how freakin' strong this storm is, such that it may pull a few deformation band surprises that could give some people a few inches more than they expect.
I'm also thinking my 5.5" might be low, given ratios. 6.5" is probably a better call, but if I get that, then I think you'll get around 5".
Replying to my long post with all the model output for 0Z. By far, the most interesting observation is, for the first time in this storm's history the pretty good consistency in track, intensity and snowfall amounts across all the models. Finally, the global models, especially the UK and Euro caught up to the mesoscale models (NAM/RGEM/HDRPS), shifting their tracks west and bringing more snow to the area.Thought it would be fun to share the snowfall maps from the entire 00Z model suite tonight, just so people can see the outcomes and variability. These all assume a 10:1, snow to liquid precip ratio, whereas we're likely to have close to 15:1 ratios so you can multiply the numbers in these maps by about 1.5 to get snow depth amounts. This is due to the very cold column (so no liquid water present), the great conditions in the dendritic snow crystal growth region, and the superb vertical velocities, driving supersaturation and crystal growth via vapor phase deposition on nucleated crystals. So here you go; I'll just keep adding these to one post, so it doesn't clutter up the board.
First up is the NAM 12 km lower resolution mesoscale model:
Next up is the NAM 3 km high resolution mesoscale model:
Next up is the 00Z RGEM, regional Canadian mesoscale model. Notice that the mesoscale models have toned down there 12" plus snowfall amounts, but are still significant to major snowstorms, especially from 95 east.
Now for the first of the global models, the 00Z GFS. Looking pretty similar to the mesoscale models now, which is what happens as one gets closer to any event - the models only have to predict out about 20 hours to get to the end of the storm now, so the errors and model to model variability will usually be much smaller at this point. Generally still seeing roughly 4-7" very close to the NJ TPK and 6-10" SE of that line and 2-4" more than 20 miles NW of that line. If it's 10:1 snow as per the model graphics; those numbers translate to about 6-10" for the 95 corridor, 9-15" SE of that line and 3-6" more than 20 miles NW of 95.
And now for the 00Z Canadian high resolution HRDPS model, the snowiest model so far, although not by a huge amount...
Next to last one is the UK global model, which is now the snowiest of all the 0Z models tonight. The I-95 corridor from Philly to Trenton to NYC is all in that yellow 20-25 mm of liquid precip band or 2.0-2.5 cm or 0.8-1,0" of liquid or 8-10" of snow at 10:1 ratios or, better yet, 12-15" at 15:1 ratios expected. Time for a nap until maybe 3 am to get up to watch the storm and stuff, as I'm on vacation tomorrow, so I'll really get to enjoy this one.
And finallly the Euro - came in about as snowy as the UK, i.e., close to a foot of snow for I-95, considering 15:1 ratios. Map is smaller, but that's all I have.
That’s because people like me come here for the weather forecast during events like this and mostly ignore all the ridiculousness on TV. Shout out to you guys that do this. It’s very informative and a lot of fun.
The snow has begun here in Metuchen, finally. Took awhile to saturate the atmospheric column with snow falling from aloft and evaporating until there was enough RH in the column to allow the flakes to make it to the ground. Still only around 40% humidity at the surface, but must be close to saturated above us. Snowing lightly and pretty windy out there - going to be a tough one to measure accurately, as it's also a dry snow, so it'll drift all over the place...
