Friday, April 18, 2014
Inquirer Daily News

Bolaris: Get ready for a Super Bowl hangover

The latest computer models see no significant reason to deviate from my earlier forecast on Monday's storm.

A beautiful Super Bowl Sunday will turn into a nasty Monday as a mix of rain, sleet and then eventually all heavy wet snow will provide the normal slick roadways, travel headaches, and a lot of when-is-this-going-to-end kind of thing.

Let me give you some good news with this storm: it is nothing like the other storms we have had this winter when bitter cold air combined with developing secondary storm systems to produce heavy dry snow bands that rapidly accumulated - combined with high 15-1 to 20-1 snow ratios when the norm is 10-1 - and painful wind chill factors.

This storm will be a milder one, and although this storm will carry more moisture than past storms, a key missing ingredient will be the polar intrusion.

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  • So, we'll see plenty of mixing at the start of the storm, which will cut down on snow totals. Plus, temperatures will flirt with the freezing mark to keep snow-to-liquid ratios much lower.

    And this wet snow will not last. Most of it will be plowed away by early evening and I'm not looking for snow build-up on the main highways. Some, yes, but not major. Secondary roadways will become snow-covered, but it will be a wet snow cover.

    Snow will stick to the power lines and trees but wind will not be a factor so I'm not looking for snapping lines or trees. Wind chill will not be a significant problem.

    We could push 4 inches, or a little more in some places, but a lot of this will be on your grassy areas and sidewalks.

    It's a fast-moving storm so banding of accumulating snow should last about 4-5 hours. We could see an inch per hour when this band develops and that is when we will pick up significant snow accumulations .

    Timing

    Mainly rain arrives after 2 a.m.

    A mix of rain, sleet and snow during the morning rush, changing to all snow between 8 and 9 a.m., earlier north and west of city.

    The heaviest snow accumulates from 10 a.m. to 2 p.m., and we could see rates of an inch per hour.

    From 2 to 4 p.m. the snow tapers and ends from west to east.

    Evening rush: A WET SNOW, will cover roadways, but mainly secondary.

    After 7 p.m., PennDOT will have most of the roads clear as it is a very easy-to-plow wet snow.

    Potential snow totals

    City: 3-4 inches, with a moderate level threat (40-50 percent) of exceeding 4 inches.

    Most of Chester, central Montgomery, and central and lower Bucks counties: 4-6 inches.

    Delaware County: 4-5 inches, with a low level threat (30 percent) of exceeding 5 inches.

    Eastern Montgomery County: 4-5 inches, with a low level threat (30 percent) of exceeding 5 inches.

    Lehigh Valley: 2-4 inches, with a sharp cut-off of snow.

    Berks County: 3-6 inches.

    All of interior southern New Jersey will be in the 3-6 inch range due to quite a bit of mixing in front end of storm.

    Southeastern New Jersey and all shore locations will see mainly rain, with a coating possible on the back end of storm.

    Atlantic City: 1-2 inches at the back end of storm.

    New Castle County, Del.: 3-6 inches. The heaviest band could set up across New Castle County.

    Kent County, Del.: Southern end, 2-3 inches; northern end, 2-5 inches.

    All points south of Dover: mainly rain.

    Enjoy the Super Bowl!

    John Bolaris

    John Bolaris PHILLY.COM
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