It seems like winter has really gotten its act together over the last 2 weeks as most now sit with above average snow and near normal January temps. I am now tracking a storm that threatens to bring parts of the Mid-Atlantic a decent snow. However, we're not included in those getting a decent snow, but the timing of when we get our snow could be worrisome.
Over the past few days our models have really come into agreement, for the most part, on how the storm will evolve. It currently appears that we'll have an area of low pressure move out of the Ohio Valley and right through the Mid-Atlantic overnight into tomorrow morning. As that happens, we should see mainly rain showers with a few areas northwest of DC having their rain showers mixing with some snowflakes that could accumulate. Our rain would have the best chance to mix in and/or switch over snow for a brief time tomorrow morning before switching back over to rain
Tomorrow, our low pressure redevelops as a coastal low, that will track up the coast. As this happens, we switch back to rain after any snow in the morning and we will stay that way throughout the day Tuesday. As cold air comes in, we may switch back to snow overnight Tuesday into early Wednesday morning before any precip ends. Basically, we have to chances of snow in this storm: tonight and tomorrow night.
This set up where we are dealing with two lows is referred to as a "Miller B" set up. A Miller B setup is never friendly to Southern Maryland snow lovers.
Temperatures, as is normally the case, are concerning to me as a snow lover. I don't think we fall below freezing until Tuesday night. Temperatures will only be marginally okay for snow tonight. The further north you are, better the chance of seeing snow, further south the opposite is true.
The National Weather Service has posted Winter Storm Warnings for the counties where the highest snowfall accumulations are likely to be. In Southern MD, Anne Arundel is included, but if you're south of Route 50, don't expect to see too much, that warning is more so for the northern end. Winter Weather Advisories are posted in locations where at least 2" of snow is possible, and PG County is included. No "core SoMD counties" are included because we likely won't meet that 2" requirement.
While we won't see a lot of snow, generally under an inch, and any snow that falls would do snow right before the Tuesday AM Rush (may linger into the Rush) and again before the Wednesday AM Rush. Because of that, school systems, especially northern ones, may want to delay to allow for any slush of icy spots to clear. If the snow falls longer and can accumulate more, the snow may last long enough in the morning to make any travel before 10am unsafe, which could lead to a close. This is true for not only Tuesday morning, but Wednesday morning as well.
The Bottom Line is that this will not be a big snow event. Most of Southern MD will see snow totals under an inch as most of this event is rain. Any snow that falls would do so before the Tuesday AM Rush and the Wednesday AM Rush. It is because of that timing that schools may need to delay or close. It's not amounts, it's timing. I'm more confident in this forecast than I was for Friday's snow event, but a few things could still change. Stay with JB Weather for the latest information.