Posted by Dave Longley - 10:30 AM Thursday - The widespread rain that moved in overnight is in the process of leaving now.  Primarily we have seen rain, but I noticed a few web cams from the Adirondacks showing some snow on the ground. 

What I think will happen through the rest of the daylight hours is the steady rain to taper to scattered showers.  We just saw some thin spots in the clouds over western New York, so it's possible that we could see a few bright spots in the clouds this afternoon.  Temperatures in the low 40s may rise a bit into the mid 40s this afternoon. 

The million dollar question though is...who will have to shovel tomorrow morning?  As is typical of this time of year, that's not an easy question to answer.  I think it'll take awhile for the lower atmosphere to cool enough to support snow in lower elevations.  However, it is very possible that as early as this evening we may see a few bursts of heavier snow that could coat the ground with snow, especially over higher elevations.  Keep that in mind if you'll be out and about this evening.

 Later tonight, we're cold enough for snow everywhere and many of us southeast of Lake Ontario could see a couple inches of accumulation by Friday morning.  The favored areas for that would be across parts of Onondaga, Madison and Cortland counties.  Honestly, I just don't see any real organization to things because of the wind direction.  It looks like a northwest wind flow, which crosses the narrow axis of Lake Ontario.  This is usually not a favorable wind flow for any real organized lake snow.  I would expect to see some snow in the area when we get up Friday morning.

During the day Friday, the arrival of daylight will likely disrupt the lake effect circulations so that we end up with the typical "spray" of lake effect snow showers.  There may very well be some raindrops mixed in across lower elevations.  The reason for this disruption is that updrafts that occur over the land due to daytime heating will take away from the updrafts within the band of lake effect snow.  With no dominant circulation in the atmosphere, no one place is favored, so everyone shares in the action of the snow showers.

A thing to watch for is the arrival of sunset Friday.  As we lose the updrafts over land, the lake effect snow band will once again show up.  Current indications are that the band could start out somewhere in the vicinity of Syracuse.  However, winds are forecast to become more westerly tomorrow night, which means more organization to the lake snows, because the air is over the lake waters for a longer period of time (longer fetch)  Also, with backing winds to a more westerly direction, the focus for lake effect will shift north into Oswego and Oneida counties.  It could get VERY snowy across the Tug Hill plateau Friday night and Saturday.  Stay tuned for that.

Feel free to add your thoughts and observations.  I'll add to this blog entry as more information becomes available through the day and into Friday.