Weekend System Looks Likely to be a Major Storm

Models continue to be coming closer together for this storm's path and impact, though nothing is carved in stone on a Thursday evening. A Winter Storm WATCH is up for all WNY Sat evening until early Monday. Light snow will reach WNY toward early Saturday evening and become moderate to heavy at times later at night into a good portion of Sunday. Winds will be on the increase, making blowing and drifting snow likely to complicate matters. Latest analysis now has a real possibility of 12+ inches by late Sunday, and one set of algorithms developed by a group of midwest mets would bring the total to higher than that. Of course, a more westward path could bring sleet in to hold down accumulations, and a more eastward path would lessen amounts as well.

Still, models have come closer together today than they were yesterday, including the NWS NAM.

Thursday Winter Storm Watch for part of WNY

The model which showed the least-est now shows the most-est in the way of snow for Thursday (the NAM). The track of Thursday's storm system has now been adjusted considerably further north, and this will bring moderate to heavy snow into the higher terrain of WNY tomorrow, and a few inches will be possible on the Niagara Frontier as well.

This has been a relatively sudden change in the model runs (even the NWS had only been talking about an inch for Buffalo in their morning Area Forecast Discussion today). I'll have more info after I finish doing my analysis and peruse through all of the models.

Mixed Bag for WNY; Bomb for East Coast?

Tuesday afternoon & evening's precip looks to be mostly liquid, with just a bit of snow at the end. But Thursday will be a different matter. Over the weekend, it appeared a storm system going by to our south on Thursday would bring us mixed precipitation; newer model runs now suggest the cold air will have sufficient depth to allow a mostly snow for WNY, though some sleet and freezing rain could still mix in--especially over the srn tier/nrn PA. Even so, this doesn't currently look to be shaping up as a big snowfall. Heavier precipitation will be falling to the south, with PA the focal point. Some lake effect snow will follow by Friday in this storm system's wake. There may be a brief period of WSW or SW winds late Friday night to bring a bit of lake snow closer to the metro area. On Friday, though, an "Alberta Clipper" low will pass to our north. While these systems can produce some general (synoptic scale) snow, the circulation ahead of such a system often disrupts the alignment of low level winds with wind shear, breaking up organized lake effect for a while. Once the Clipper goes by, winds will veer to W or WNW and, as has been the case all this season so far, that will take us back to multiple bands of lake snow away from the metro area.

During the weekend, 2 global computer models (the GFS from the NWS, and the ECMWF from the European Center for Medium Range Weather Forecasting) point to a strong wave moving off the Atlantic seaboard and exploding into a "bomb" of a nor'easter for cities like NYC and Boston--though there could be a change to rain for awhile. Currently, the models take this storm too far to our east for it to have a direct impact on our weather, but a later adjustment in its projected path to the west/inland, could paint an entirely different picture--snow and wind for us, and rain & wind for the east coast. Right now, there is no indication of that happening. As always, we'll keep you updated if there's a change.

SPEAKING OF UPDATES, I'll continue to update the White Christmas Chances thread on a daily basis this week as well.

NPA Ice Storm Warning Sun thru Mon AM...

In addition to the Winter Weather Advisory for all of WNY & NPA, there is now an ICE STORM WARNING for Potter & McKean counties in NPA. This extends from 1pm Sunday to 7am Monday. Down in that direction the models are indicating the longest stretch of mixed precip as well as the most amount of precip. In other words... mixed precip will be the dominant precip type this afternoon and tonight in NPA. A quarter of an inch of ice accumulation is possible in that direction. With this amount of ice accumulation falling tree branches and power outages could possibly occur. Mary Beth and I will keep you posted!

For today though, first snow will spread from S to N early this afternoon. Then a transition to more mixed precipitation will also follow the same progression... S to N this afternoon and into tonight. Some minor snow accumulations (an inch or two) are possible especially for the northern counties where it will remain snow the longest. Down along the S. Tier and NPA, precip will remained in mixed form through Monday AM.