Snow coming; storm track critical
Once again, Central Maryland is on the bubble, while a powerful winter storm works out where the devil it's going. A slight drift to the right or left at the right time and we get mostly rain, or we get a half a foot of snow. Or more?
For now, the National Weather Service out at the Sterling forecast office isn't ready to commit either way. This morning's discussion suggests the computer models are bringing the Gulf storm back closer to shore. That's good news for snow lovers.
The storm track forecast had been pushing eastward. That dragged the heaviest precipitation out
of the Appalachians and into our laps. But it kept going, which would have had the rain and snow falling on the ocean. And what use is that? Right?
This morning, the computers seem to be reversing course, bringing the main axis of the snow back our way. This morning's discussion puts the storm "somewhere off the mid-Atlantic seaboard Monday night." One run had the surface low just off the coast. Says Sterling:
"IF THIS SCENARIO PLAYS TRUE...LIKELIHOOD OF
HEAVIER PRECIPITATION OVER THE AREA LATE MONDAY AND TUESDAY WOULD
BE MUCH HIGHER. WITH COLD AIR BEING PULLED SOUTH AND EAST BY THE
SURFACE LOW...MUCH OF THE PRECIPITATION UNDER THE UPPER LOW WOULD
FALL IN THE FORM OF SNOW."
That said, forecasters said they are still "not entirely sold" on the scenario. The official forecast for BWI has rain starting on Monday, changing to snow after midnight Tuesday. The snow continues into the morning, but tails off after lunch. There is no accumulation prediction yet. But if their forecast holds up, we can expect schools to be affected Tuesday for sure.
Then there's AccuWeather.com, always a reliable source of encouragement for snow lovers - and despair for the rest. They've already got their snow map out, calling for 3 to 6 inches here, and lots more along a corridor to our north and east. They also hedge their bets, noting that a change in the storm's path as it's currently forecast, could change everything - from mostly rain to lots of snow.
Here's their main story this morning.
Comments
Oh mannn. Even though it looks good, I still don't trust, at all. I looked at both NAM and GFS and noticed the changes. It looks like a totally different storm forming, rather than the original one riding the coast. And its like a small pocket of precip kinda hangs around us.
I have one question for you.. Is there any chance that this could be an all snow event? (rather than rain first, then snow) That is in the situation it is a 3-6 inch snowfall for much of Maryland.
Oh yeah, I have heard a couple rumors of a major snowfall. Even on that accuweather it has 6-12 inch swath going into where I live. I also saw some GFS total precip map, and it showed 16-18 inches for much of Maryland. Pshh, I wouldn't believe that if it was happening.
FR:An all-snow event? I doubt it. But that will depend on how fast the cold front blows through and drags in cold air behind it from the north and west, and how much precipitation continues to fall after that. There are some suggestions that "cold air advection" will happen sooner than some models had forecast, and that the changeover will happen sooner. But they're all still guessing at this point.
Posted by: Dakota Smith | February 1, 2009 10:38 AM
The latest run of the global model (GFS), just out, has turned the zig to zag (weaker and further out to sea).
FR: They don't call the GFS "Goofus" for nothing. We'll soon see how good it really is.
Posted by: CapitalClimate | February 1, 2009 11:54 AM
Sooooooo, what you're saying is... nobody has any clue, and doesn't want to commit to any sort of prediction?
That pretty much sounds about right! ;-)
Posted by: Sam | February 1, 2009 1:14 PM
I may be off-base, but if the temperatures are in the 40s on Monday, and do not venture below freezing until late at night, how can we expect snow to stick? Won't the ground be too warm? Is it expected to get that cold that quickly?
FR: The cold air will be moving in during the day Monday, but not fast enough to allow this thing to begin as snow. It will be rain, changing finally to snow around midnight and continuing into the morning Tuesday. Or so say the folks in Sterling. I suspect it will take some time to stick to the roadways. Temperatures will be dropping Tuesday toward a low of 20 Tuesday night. That said, these guys really don't know much yet about the timing of all this cold and precip. The models are still all over the lot.
In the meantime, what a great day today! High of 59 degrees at BWI - 17 degrees above the average for the date, but far short of the Feb. 1 record of 75 degrees, set back in 2002.
Posted by: Joel | February 1, 2009 3:42 PM
And the afternoon run continues zagging . . .
Posted by: CapitalClimate | February 1, 2009 5:03 PM