A Meteorological Bomb??? Yes.. and will bring HEAVY Snowfall over Weekend!

Ok, so the weekend continues to get more interesting. Latest run of the Euro weather model is now putting out nearly two inches of total liquid equivalent for the weekend storm... and if today's data is correct, about half of that could fall as snow. Meaning, we now how a significant storm to monitor.

There is good agreement between the Euro and this mornings run of the 3k NAM which really increases my confidence that this "potential" heavy snow event will infact materialize for a good chunk of Western New York.

The storm in question is currently embedded in some powerful upper level winds that are just now beginning to eject from the Rockies and into the South-Central US in the form of a deepening trough of low pressure.

As it interacts with "a coupled jet and soon to be negatively tilted trough" this low will undergo rapid strengthening during the day tomorrow. So much, in fact, it will likely be classified as a METEOROLOGICAL BOMB... meaning the central pressure will drop more than 24 mb in under 24 hours. In this case, the 3k NAM has it dropping from 1004 mb at midnight tonight to a remarkable 974 mb midnight tomorrow night. That's a 31 mb drop in 24 hours. Wow, that's impressive!

Ok, so what does this mean?

Showers look to develop ahead of this low later tonight and looks to become a widespread cold rain with temps in the upper 30's by morning on Saturday. From there, as the low rapidly deepens, colder air get's drawn into the backside of this storm causing a quick change over from rain to a VERY HEAVY, wet snowfall that looks to cause some major head aches on area roadways and could also come with some power outages.

Timing

Right now it looks like we'll see that changeover from rain to snow during the early afternoon hours in Buffalo and between 3 and 5 pm ET across the Rochester area with the transition occuring around 6 or 7 pm for Syracuse. The snow will quickly become heavy with roads becoming snow covered by around dark. I expect quite a mess to develop during the evening hours with with a "greasy and sloppy" nature of the snow which will stick to just about everything. The heavy snow looks to come to an end quickly by late evening diminishing to just a few snow showers overnight.

How much?

Current (12z run) hi-res nam is showing the potential for widespread 5 to 9 inch amounts between Rochester and Buffalo by Sunday morning with the largest totals occuring in the higher terrain with locally a foot in the favored snow belts southeast of Lake Erie as lake enhancement increases totals. Totals will be a bit less east into the Syracuse area. I also think totals will be less north of Hwy 104 as you get closer to Lake Ontario because of the marginal surface temperature which will lead to more of a rain/snow mixture right on the lake with perhaps only a slushy inch or two.

What do I think?

Because of the wet nature of the snow these won't be the largest totals we've seen this season. However, it will come VERY fast likely creating a real mess on area roads Saturday evening. For those who have holiday parties to attend or travel plans, this storm should be monitored. At the very least, this storm will need a Winter Weather Advisory for difficult travel late tomorrow.

I will be watching the situation closely going into the weekend and will have streaming updates on WxLIVE as needed. Stay tuned.