BLOG: UPDATE ON THURSDAY NIGHT/FRIDAY MORNING SNOW

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A quick update this morning on a fairly minor (although impactful) snow event coming our way Thursday night into Friday morning.

THE SETUP

Cold, arctic air will be on the move across the northern Plains and Rockies and will run into a much warmer air mass to the south. An area of low pressure will ride along the boundary between those air masses and cause precipitation to break out here by early tomorrow evening.Temperatures locally will be in the mid 40s before the precipitation arrives tomorrow...and this will be important. The ground will be warm and it will take a while for snow to start sticking efficiently. More on that in a second.

TIMING

Precipitation will arrive between 4pm-7pm on average and will fall in the form of RAIN initially. Snow will start mixing in, first in the north then in southern areas, as we go deeper into the evening.Everyone will see a changeover to snow overnight. The snow will be heaviest and have the easiest time accumulating after midnight.The snow will taper to flurries Friday morning and midday.

ACCUMULATIONS

I think the graphic I showed last evening still works pretty well for much of the area. The highest odds are for an accumulation around 1.5"-2.0" but there is a chance for higher accumulations, especially in western PA.This is still a pretty tricky forecast. Our best-performing model (overall....even it does have bad days), the European, is less impressed with the snow. This makes me skeptical about the higher amounts shown on some of the other modeling.  The European is the purple line.It's March and will be quite mild before the snow arrives. Some of the liquid with this storm will be "wasted" on rain/mixing and snow falling with temperatures around 32-34. This can lead to lower snow amounts.  The one thing it has going for it is the snow is falling at night. If this came during the day, even with temperatures near freezing, hardly anything would stick on paved surfaces.

IMPACTS

Look for increasingly slick conditions late at night, mainly after midnight. I would expect some 2 hour school delays for some districts Friday morning. This snow will be MUCH different than the snow we had late last week. This will be much wetter, great for making snowballs but harder to shovel.

WINTER NOT OVER

The weekend storm will be a miss for us, but I have increasing confidence we will be impacted by snow early next week...probably Monday night into Tuesday.Meanwhile....enjoy the sunshine today but WIND is the story! Gusts to 50 mph later.