It looks like tomorrow will be a very interesting day around here. One of those days that we really haven’t seen to much of this season, a day of winter! When meteorologist Cecily Tynan gave the Accuweather February outlook (the first two weeks of the month) she talked about how the overall pattern would be mild in the Delaware Valley, but from time to time we would see a cold shot from “Mother Nature”. Well this weekend will be one of those cold shots, and bitter cold it will be!
An arctic front which is bringing 50 degree below zero wind chills to the high plains this morning will be barreling south eastward over the next 24 hours. This front will slam through the region on Saturday. Out ahead of it, most forecast models want to bring a small, but rapidly intensifying area of low pressure up the coast from Virginia to New England. The saving grace with this is how quickly it’s moving. With a fresh shot of arctic air approaching from the west, if there had been just a little more blocking over the top in Greenland to slow this thing down, it could of been a big storm for us! With that said, the blocking (which slows up traffic so to speak in the mid levels of the atmosphere) is very weak so the storm will swiftly head up the eastern seaboard and cause only minor headaches for us.
RAIN/ SNOW LINE
The question that I have been trying to answer for the past two days is where will this rain/ snow line set up? Had the ocean tempertaure been in the mid to upper 30s right now, like it’s suppose to be this time of the year, we really wouldn’t have much of a rain/snow line to deal with. Maybe the immediate shoreline, but that would be about it. However, the fact that the ocean temperature is in the mid 40’s combined with a developing, moderately strong east wind, this will force that milder ocean air inland across southern New Jersey. This means most areas south and east of the Delaware River will start out as rain or some kind of mix overnight into Saturday morning. Yesterday I had this same exact area in the accumulating snow zone, but this morning Im going to have to push that zone farther west.
Let’s say in a line from Trenton, through Philadelphia into Wilmington, from that line south and east to the shore you will all start out as rain or some kind of mix. From that line, points north and west, it’s all snow. My thought at this time is if you live in southern New Jersey, within 35 miles or so of the Delaware River you will chang over to snow at some point during the wee hours of the morning. However, the counties of Cumberland, Atlantic, Cape May and eastern Burlington will more than likely still be getting rain. Eventually, as our winds begin to shift out of the northwest and this storm passes by to our northeast everyone will change over to snow.
When all is said and done it looks like a quick 1-2″ in the I-95 corridor from Wilmington to Philadelphia to Trenton. Areas just to the northwest of the Delaware River being closer to the 2″ line and interior sections of southern New Jersey closer to the 1″ line. There will be a slightly heavier, more concentrated area of 2-3″ with this in central Chester, Montgomery, Bucks and Hunterdon counties. This will more than likely include the Lehigh Valley as well. I’m waiting for the new forecast guidance to come in to determine whether or not I want to include that area. When it comes in I will post it on my fan page.
SLICK SPOTS DEVELOPING
The roads will remain mainly wet with this as temperatures this afternoon are expected to jump up into the mid to upper 40s again. However, my concern is for when the arctic front blasts through. Temperatures will immediately drop 10 degrees or so with the passage of this front. So roadways, sidewalks, bridges and overpasses, things of that nature that are untreated and appear to be just wet will begin freezing over. This is when there could end up being some issues out there with slick spots. Not necessarily when it’s snowing, but afterwards. There could also be a quick snow shower or squall with the front as well that could coat the ground. Temperatures then really begin to tail off after sunset with gusty winds dropping wind chills down into the mid teens, possibly even colder. Single digit wind chills are a good bet in the Lehigh Valley.
RANKING THE STORM
On a scale of 1 to 10 with a 10 being crippling and a 1 being a nuisance event, this is once again going to fall in to that 1 category. At least as far as the snow is concerned. This will not be a big deal. With that said, I do not want you to let your guard down Saturday afternoon. Even though the snow will probably have stopped by then, as the cold front slips through and those temps plunge everything will begin to freeze. So there will more than likely be more problems with the quick freeze rather than the snow. On top of that if we do end up getting that quick coating from an afternoon snow squall, now you will have snow covering up icy patches. So please be careful and take it slow tomorrow afternoon.
I will update again on my fan page later this afternoon.