Storm #2 featured above is just a prelude to what's coming later in February. Though I will end up one day off for the projected arrival time (original call January 13 was for Storm # 2 to occur in the 1/29-31 time frame), it will be nice to finally have enough snow to cover the grass.
I know you want the full story on this storm, but a brief update is all I can do for now until tomorrow morning and then more tomorrow evening. But here's what it looks like to me:
1. CLIMATE TELECONNECTIONS point to a coastal storm: The Pacific North American (PNA) Index is positive, the North Atlantic Oscillation (NAO) is in a negative phase but driftly slowly toward neutral. That as some of you know is a key indicator for me, because when the NAO (a measure of air mass movement in the North Atlantic Ocean) backs off from strongly negative, it means there will be sufficient, if not fresh, cold air available as a coastal storm turns north.
2. ALL ABOUT THE TIMING. For the I-95 corridor from DC to Philly, the timing of this is terrible for commuters but wonderful for students and teachers hoping on a snow day, or at least some kind of something to give you a little time off. The NWS has been backing the temps down all day for Thursday, off from a high of 40 to now just 34 in the Dundalk area. I use my town as a gauge because we are southeast Baltimore County, right along the Chesapeake just east of 95. If the forecast HERE calls for snow/sleet/freezing rain, you can bet the rest of the Baltimore Metro area will see all frozen precip and coming at just the right (wrong) time.
3. WHERE'S THE HIGH? Some of you know the old rule: "Predict the High and you predict the storm." Problem this time around is there won't be a High Pressure system in the right place (SE Canada or upstate New York) to deliver fresh cold air. Instead the high moves off the Mid-Atlantic coast Wednesday, and the storm arrives on leftover cold air Thursday. Combine that with the expectation this will be a fast moving system, and you can see why snow amounts will stay on the low side, and this may wind up more of an ice event for many than snow.
WHAT ABOUT SCHOOL? For DC/Northern VA area schools, it looks more likely you'll be closed Friday due to the ice potential. For Baltimore Metro schools, this will be a tricky call at two different times:
- Thursday afternoon: Precip (mostly snow/some frozen mixed in) will start after lunch and spread northeast. Travel will deteriorate from 1PM on. Early dismissal? Don't count on it, because I doubt the radar will look so ominous so as to suggest school officials should pull the plug at 11AM based on a projection of something that's 2 hours away.
- Friday morning: Considering what the map above indicates, this will be a tough call. For everyone along I-95 and then to the north or west, snow will probably mix with sleet and freezing rain for a few hours overnight, then change back to snow in the morning. We are not talking much more than 3 inches for anyone. In fact, I'm leaning closer to 2 inches for most areas south of Mason-Dixon given that mixed precip will lower amounts. The kicker will be that blob of green you see wrapping back around the storm. For many Maryland districts: Balt Co, Harford, Baltimore City, Anne Arundel and Howard, I can see a scenario where everyone calls for a 2 hour delay, then 15 minutes later says they will reevaluate at 6:45 AM. If that band of wrap-around snow starts up right at the time of "reevaluation" you'll see schools change to closed. This happened twice in recent years...January 4, 2003 (snow) and February 6, 2004 (ice).
Finally, what is the point of my headline? No it has nothing to do with Cialis. It means that this storm will present only a few precious moments where the right decision can be made quickly and easily. Official forecasts will probably flucuate more in the next 24 hours, driving you crazy when you're looking for consistency and there is none to be found. A special note of warning to my teacher colleagues: A lot of things have to come together just right for this storm to deliver a day off, so maybe the headline should really say: "If the moment is NOT right, will YOU be ready?" (for class on Friday).
Next update in the comments feature Wed 5:45 AM, followed by Pre-Storm Report Wed evening after 9 PM.
- Valid for the period Friday, January 26 to Tuesday, February 6.
ABOUT THE FREQUENCY OF POSTS: Until January 30, I will be generally either preparing, issuing or grading midterms and quarter grades. This is the last post until after I have turned my grades on time, so I'll see you all back here on the 31st and we'll find out together if this projection pans out.
IT'S A GLOBAL WARMING WINTER
OKAY FINE, OUR WEATHER IS BEING INFLUENCED BY GLOBAL WARMING. THANKS FOR CLEARING THAT UP, AS IF I DIDN'T KNOW. So what about the snow already?
Oh yeah, I was going to do some analysis of that on here sometime. Here it is:
Storm # 1: Projected for the January 22-25 time frame. Computer models continue to advertise some kind of Tennessee Valley system moving to the coast, which a moderately cold High placed to the north. Not the perfect setup when you consider the NAO is going Negative and that will tend to push storms more to the south. The following set of graphics are three models that indicate what is anticipated for 7AM January 22. First,the GFS:
What's significant about these two maps is they both show a storm reaching the Mid-Atlantic coast fairly juicy with a potential for rapid development once there. The culprit for this lies with the sea surface temperatures in that same area.