Next storm may be sloppy repeat
You can say one thing for this winter's weather. It's consistent. Complex storm systems bring southern lows up, or off, the coast, while another low moves out of the west or the Great Lakes. The two fail to merge or "phase," and we get a few inches of snow or a sloppy/icy mess.
And that seems to be what's shaping up again for Thursday night into Friday. Forecasters at the National Weather Service forecast office in Sterling, Va. are tracking a weak southern low that they expect will emerge somewhere off the mid-Atlantic coast by Thursday night. Another storm system sliding in from the west is not expected to hook up with the coastal low in time.
Depending on storm tracks, that could mean one of several outcomes, forecasters say. One computer model sets up the coastal low off Delmarva with rapid intensification Thursday evening. That would mean snow for the entire forecast area until daybreak Friday.
Another model slows the storm down and takes it across Delaware Bay. That would allow more warm air into our region, mixing up the precipitation and limiting accumulations, if any.
While the other models seem to be favoring the latter scenario, forecasters at Sterling, being extra cautious, are siding with the former. AccuWeather.com is expected 1 to 3 inches in Central Maryland, with 3 to 6 to our north and west.
The official forecast at this point (late morning Wednesday) calls for a 90 percent chance of snow at BWI-Marshall, beginning after 9 p.m. Thursday night, with an overnight low of 28 degrees.
The snow chances slip to 40 percent Friday morning, ending before noon. Skies would then clear off quickly, leading to a sunny but colder, gusty day, with a high back down in the mid-30s. Friday night lows would drop back into the teens. And while the weekend would be sunny, temperatures would struggle to reach the freezing mark Saturday.
The NWS snow map (right), at least through 1 a.m., shows less than an inch in Central Maryland. But that series of forecast maps does not yet get us to daybreak Friday. Watch this space.
Eric the Red, a professional forecaster from Baltimore, is siding with a reprise of recent storms, with little accumulation, again:
"If you take the just-in guidance at face value... it would be 1-2" of snow in the DC area, 1-3" in central MD, and 2-4" across northern MD. As I mentioned yesterday, if I had to pick which way this would go... it would be lighter, in line with persistence."
Our next shot at some accumulating snow may come early next week. And AccuWeather.com forecasters see the pattern continuing: "There are more storms on deck for the following couple of weeks. At least one of these has the potential to be another blockbuster for some areas."
Stupendous snow total for the season so far at BWI-Marshall Airport? 4.7 inches. We haven't even reached the low-bidder (7 inches) in our "Guess the Season's Snow Total Contest."
Pitiful, don't you think? Seems to me we passed 4.7 inches in the first few hours of the Dec. 18-19 storm last winter.
UPDATE, 2 p.m.: Eric the Red has updated his outlook for the Thursday-Friday snow, and added his speculation about next week. And next month. Read on below.
"Next week... Jiggyness. Models are all over the place... but on this they agree: Something will spin up over the southern US and move northeast.
"The NOGAPS has a snowstorm Monday night, but it's outta here by Tues. The GFS has what looks like freezing drizzle or light snow Monday night, and then an extended period of light to moderate snow Tues into Weds morning as a low crawls up the coast (yeah, right). The Canadian [model] takes forever to get the storm out of the south... and it brings it right up I-95... with rain or ice Weds night and Thrs. Ugggghhhh.
"The ECMWF has a very ominous-looking low in the northeastern Gulf on Tuesday... and based on the current fcst track, would bring a world of hurt to the eastern U.S. Tuesday into Weds... like heavy snow, sleet, freezing rain, and rain as the low tracks right up the I-95 corridor.
"So, next week could very well be the make-or-break storm of our winter. Why? well I'm flattered you want to know. Read on.
"Last week of January looks like it may very well spell the end of an era. After 18 months of north Atlantic blocking highs... the last couple of long-term model runs finally have a wholesale pattern change, as the peristsent blocking high over the northern Atlantic breaks down and is replaced by fast, west-east flow at the jet stream level over eastern Canada and the north Atlantic. This in turn would ultimately put an end to the never-ending assault of cold air in the eastern U.S.
"The northern Atlantic pattern is expected to do a full reset on or about Feb 1, so we may very well be dealing with the last 2 weeks of wintry weather, barring a quick return of the blocking high (which based on the latest fcst charts does not look likely). Basically, once the block breaks down, we'll start to see an onslaught of much milder, Pacific air masses. Again, the target date is ~ Feb 1. That leaves us 2 weeks to get some snow."