#1: QUICKIE FOR FRIDAY A.M. RUSH
The first snow threat comes early Friday morning, as a small rain event turns into a small snow event. I use the term “event”, since it’s just not big enough to be called a “storm”. A couple of inches of snow is a storm in Atlanta, but not around here-especially when the roads are warm at the start.
WARM AIR/WARM ROADS-BUT NOT TOTALLY
We got up to 56 degrees Thursday-after 62 Wednesday tied a record. So the roads are warm. The air is still warm, so precipitation will start as rain all across our area. If the change to snow would happen in the middle of the day, we could be pretty sure it would melt as it hit, and problems would be minor at best. But the change to snow is expected near the start of the A.M. rush (4-7am). And it could change from a fairly heavy rain to a fairly heavy snow quickly. I’m talking about the big, wet flakes that stick to everything. When it comes down hard, it can reduce visibilities to near zero, making it hard to see the traffic ahead. That’s not so minor.
ONCE THE SNOW STARTS
This is more like a spring snow, with rain changing to wet snow, and temperatures remaining at or above the freezing mark. Roads can’t be pre-treated, since the rain would just wash away the chemicals. So, if the snow comes down hard for a while, roads could get slippery-especially the less-traveled ones. Any heavy snow won’t last very long, so it may be best to just pull over and wait it out if you run into a snow burst.
Since it’s not really a storm, the snow will end quickly, between 8 and 10am depending on where you are. And the sun will come out, pushing temperatures back into the 40s. That will melt the snow that just fell, and the afternoon rush will be nice and dry. So will the weekend-nice and dry.
Here is the snow forecast map from NBC10:
Some spots in the white area could see locally higher amounts. And the farther away you get from the ocean, the less snow you will see. It’s what we sometimes call a “backward storm”, since the N&W areas usually see more than the shore……(OOPS…I didn’t mean to call it a “storm”)
#2 MORE OF A REAL STORM-BUT PROBABLY NOT HUGE
Computer models have been showing signs for more than a week. An Arctic blast will be moving into the area by the middle of next week. The possible storm is just ahead of that. But, unlike our blizzard from a couple of weeks ago, this set-up is far from classic. There will be multiple storms developing between Monday and Wednesday, and not one single, big storm. In fact, the biggest one will probably move out to sea Monday. The one on Tuesday has more potential to bring us snow.
Here is the computer forecast map from the overall world’s best model-the European. And it’s not just the EURO, it’s the “ensemble” of that model. It’s an average of the 51 times the model is run twice a day. So, it’s “the best of the best”:
The LOW is in a favorable place, and the rain/snow line is far enough offshore to make us predict snow for Monday night into Tuesday. But it’s not a real intense LOW, which would be needed to give us a big storm. It’s still too early to talk about amounts, but it does have the potential to give much of our area accumulating snow.
Glenn “Hurricane” Schwartz
Chief Meteorologist, NBC10 Philadelphia