A high impact winter storm is likely to impact the region on Wednesday. Yes, schools and travel are likely to see significant impacts . This is all due to a storm that will move to our west, overspreading precipitation across the Mid-Atlantic late Tuesday into Wednesday. You may be thinking to yourself, "The biggest Mid-Atlantic snows occur normally when a storm slides to our south or off the coast to the east. How is this storm to our west going to give us winter weather?" An area of high pressure to our north will help to channel in cold air Tuesday and Wednesday. It will be because of that cold high to the north that will allow the precipitation that falls to be a wintry mix. The National Weather Service has gone ahead and issued a Winter Storm WATCH for many in the Mid-Atlantic. As you can see below, locally this does include the colder areas of Anne Arundel, Charles, and Prince George's Counties. Others outside of the Watch (like Calvert, St. Mary's, and Westmoreland) will also see snow. However, it likely will not be the magnitude the northwestern zones will see. These types of set ups typically favor communities to the north and west of I-95. Because these zones are normally colder it is hear that sees the most snow and ice. However, that area of high pressure, that's pumping in the cold air, is very strong. That will lead to everyone initially starting as snow Wednesday morning. The snow could be heavy at times. Some computer model data shows areas south of DC seeing an enhancement in snowfall totals because of the heavy snow. I'm not sold on that solution yet, but it is a solution that is on the table. As you see in the timeline below, by mid-morning everyone should be seeing snow. As warm air from the south works in, the change over to sleet and freezing rain will occur around midday. This is likely to create an icy mess, especially north and west of I-95. The warm air will continue to work north, eventually turning everyone over to rain. Again, a period of snow is likely for everyone. From Ridge, to Huntingtown, to La Plata, and Annapolis most should see a period of snow in the morning. How long that period will last is uncertain. However, I would think we should see a good 3-6 hours of snow. Right now it looks like the highest totals will be northwest of I-95, where snow lasts the longest. As mentioned before, some models have consistently shown some enhancement to snow totals across areas south of DC. This is before these models show the snow hanging on longer, and showing that snow as very heavy snow. Some of your weather apps may be showing higher snow totals for Southern MD than I have shown, and that's why. I wouldn't hold my breath for that solution, but it is something to keep in the back of your head. Shown below is my first call on snowfall. As mentioned before, many are likely to see a period of ice between the switch over from snow to rain. This transition period when the ice falls is likely to last the longest out west; where it is coldest. Western zones could see a high impact from ice, totaling over a quarter inch. Just to the northwest of I-95 moderate impacts are likely, with ice there totaling from a tenth to a quarter inch. Along I-95 and to the slight southeast, a glaze of ice could lead to some elevated impacts. Locations along the coastal plain are not likely to see an over abundance of ice. This is because those communities sit near, or right at sea level. The "warm" water temps above freezing should make the transition quicker for those areas. Elevated: Glaze - .1" of ice Moderate: .1" - .25" of ice High: Over .25" of ice A high impact winter storm is likely to bring snow, ice, and rain the entire Mid-Atlantic. While areas north and west of I-95 are likely to see the highest totals of snow and ice, everyone should see wintry weather Wednesday morning. I do believe that many schools are likely to close on Wednesday and travel will be significantly impacted. This is a low confidence forecast. If temperatures warm quicker than expected, or a dry slot develops, totals could be lower. On the other hand, if the cold air stays longer or there are heavier snow bands, totals could be significantly higher. There's a lot to watch over the next 36 hours leading up to this storm. Prepare now, and follow JB Weather on Facebook and Twitter for the latest updates.
Lead Forecaster -John A. Bordash
0 Comments
Leave a Reply. |
Archives
August 2020
Categories
All
|