Foot's Forecast | Weather Intelligence

YOU'RE NOT GETTING OUT EARLY

(oh, I meant to say that was only for Howard and

Anne Arundel Counties in Maryland! Sorry I didn't clarify sooner ;-)

WED 12-5 EVENING POST GAME COMMENTS AND ANALYSIS IN BLUE. Text in black was written at 5:30 AM on 12-5. As a fast moving Alberta clipper races east across the Mid-Atlantic, students and teachers in West Virginia, Northern Virginia and Central Maryland will be noticing the light flurries at lunchtime increase to light snow throughout the day. WHAT REALLY HAPPENED: 8:00 am - 9:00 am start time across the Baltimore Region. By last period or mod, with snow becoming steady, teachers will no doubt be pestered with the same question over and over and over and... you get the point. I don't even have to post the question. Students started up with "the question" even before the snow started.. prior to homeroom no less.

By mid-afternoon Wednesday, enough snow will have fallen across central and northern Maryland, and Northern Virginia to coat the grass, untreated sideroads and sidewalks, but not enough to disrupt traffic, main roads or secondaries. Reports started coming to me by late morning that secondaries were becoming snow-covered in northern and western parts of Baltimore County. The daytime arrival of the snow is such that roads will get a little slick, but movement of vehicles will warm surfaces enough to prevent a glaze from developing. Highway and school grounds crews working have ampletime to salt or clear roads / sidewalks and keep up with any changes in snow intensity throughout the day. Although there is plenty of cold air in place the approaching clipper system has less than 1/2inch of liquid equivalent moisture with which to generate snow. As my Earth Science classes calculated on Tuesday analyzing the latest computer models, our projections came to this:

Available moisture: .30 " x a liquid to snow ratio of 1:12 given colder air = 1.56 inches across the Baltimore metro region. Well, that was, like, a tad way off. I measured 4" in my yard, which seems slightly higher than 1.5" That's the amount I'm pegging for accumulation at BWI airport, and we will grade the clipper on that number. Ouch this is going to hurt, gonna be an ugly grade, possibly the worst ever, because 4" on a call of 1.5 is a 62% deviation from the forecast, which nets me an accuracy rating of 38% = E-----

I believe lesser amounts the farther north you go toward Pennsylvania. (Wrong: Bands of snow streaking across the PA-MD border had dropped up to 4" by mid day.) Slightly higher totals of 2-3 inches are likely on the Eastern shore as aptly pointed out by one of our loyal readers, Mr. Justin Berk of ABC2 News. Justin also made important mention in some emails we exchanged yesterday about the possibility of several bursts of snow in the evening hours before ending. His point is well to be considered that this could leave wet roads following the evening rush with the potential to refreeze overnight. Given that idea, there is the outside chance of some school delays Thursday. Update: Anne Arundel County already submitted a 2 hour delay as of 9:12 PM.

As for today, it seems prudent to expect that schools WILL NOT dismiss early (Wrong again..only Baltimore City Schools, Howard County and Anne Arundel were the holdouts.) but WILL LIKELY CANCEL AFTERNOON AND EVENING ACTIVITIES considering the snow should be increasing from afternoon into the evening. (That was easiest call of them all overall. Okay enough rhyming.) The biggest problems will occur in the evening traffic period due to slick roads and reduced visibility.

The only possibility I can see for an early dismissal is if snow intensity starts earlier and stronger than expected, and by 12 pm it is clear roads are becoming snow covered... prompting a 1 hour early call. (Well, that's exactly what happened, I just didn't think it had that good of a chance of really panning out the way it did.) But I think that's still highly unlikely given the timing of the heaviest snow to be arriving when elementary students should already be home. (Good thing most counties called a 1-2 hour dismissal, helped reduce potential for accidents given that moderate to heavy was occurring while I was driving at 3:40...about the time some elementaries would have normally dismissed.)

Previous December 5th's have delivered better snow season kickoffs, so the best part to take away from this year's event is that it will look nice on your holiday decorations, assuming you took advantage ofthe dry weather in previous weeks to get it done. You could take some pretty pictures for your screen saver or greeting cards, and prove to your distant relatives that it really does snow in Maryland, occasionally. (Justin Berk of ABC2 News pointed out that snow has fallen in the area at least 4 of the past 6 years on this date, including Dec 5'ths in 2002, 03, 04, 05 and now 07.)