Forecaster, Capital Weather Gang
Wednesday, November 19, 2008 1:00 PM
Is it time to fire up the snowplows and stock up on shovels and salt? Or will winter be dry and temperatures mild? Matt Ross of the Capital Weather Gang was online Wednesday, November 19 at 1 p.m. ET to talk about the team's just-released winter outlook report.
Matt Ross, the lead forecaster for the outlook, has been interested in weather since early childhood, including a specific fascination with snowstorms and extreme weather events. Although he passed on a career as a meteorologist, his enthusiasm for both weather and statistics, particularly related to the D.C. area's local climate, continues to strengthen as he gets older. Frustrated with the region's lack of snow, Matt has been known to chase after the white stuff, including recent trips to northern New England and the Tug Hill region of New York during majorsnow events. Of particular interest to Matt is the study of analogs, or past weather data as a means of predicting long-range seasonal patterns. Matt owns a legal staffing agency and resides in Mt. Pleasant.
The transcript follows.
Matt Ross: Hi Everybody. Thanks for swinging by. Here is the link to the outlook in case you haven't checked it out yet. As you will see, we are expecting a colder and snowier winter than last year, but no blockbuster. I'll try to answer as many questions as I can. Enjoy.
Mount Vernon, Va.: Last winter we got a very cold snap in December, and that turned out to be the worst of our winter. Is it possible that this cold air through the end of November will break with a warm-up and the rest of the winter will be comparatively mild?
Matt Ross: I don't think that is likely. The pattern is already a lot more interesting than last winter, and I think while we will see the pattern relax at times early this winter, there will be ample opportunity for it to reload. December averages almost 5 degrees warmer than January, so even though we are calling for a warm-up relative to normal, a +1 or +2 January is still pretty cold and cold enough for snow chances if we can get the timing right.
Silver Spring, Md.: What do you see the NAO and associated teleconnections doing this winter? Do you think that we will have a favorable pattern WRT to the NAO?
Matt Ross: For those that don't know the NAO (North Atlantic Oscillation) is an index that measures pressure differences. A negative NAO is often evidenced by a large ridge of high pressure over Greenland and is typically good for snow and cold in the mid Atlantic.
I think the NAO is hard to predict. In terms of it averaging positive or negative, I can't say. But we are already seeing some blocking patterns near Greenland that we didn't see last winter. This is a good sign...
Arlington, Va.: Hey Matt and all of CWG. So is this the year? Finally? I'm a transplanted New Englander who has been here since '97 and can count on one hand the "big" storms we've had since. Any hope? Help! I bought new boots and everything.
Matt Ross: Us snow lovers are always hoping for the big one. You may recall that although it melted quickly we did get a pretty big one (8-14") in February 2006, so I don't know that we are "due", but I think we have a good chance for at least one 6"+ storm, something that eluded us the last 2 winters.
Impact of weather on Metro: Given Metro's mediocre past performance during bad weather, how do you see this winter's forecast impacting Metro's ability to handle and move a growing ridership when faced with snow or icy conditions?
Matt Ross: I think for Metro the issue is usually timing, and since D.C. is a particularly hard place to forecast for, I think some trouble is unavoidable.
Arlington, Va.: I'm forecasting a snowy winter based on the fact that I saw actual flurries yesterday in SE, D.C. and my partner saw a few in NW, D.C. Early flurries are my omen. I don't need any fancy science.
Matt Ross: Nothing wrong with "feel". And I have to say, yesterday's wind, cold and flurries did have the "feel" of a good omen for winter. Hope you enjoyed.
Anonymous: I have been living in D.C. for all my life (36 years-old) and it appears that since 1990 we have had less and less snow.
Does the historical data support that observation?
Matt Ross: To some degree, yes. We are in a weird 20 year cycle, where we either have a huge winter or a disappointment, snow-wise. In the 60s, 70s, 80s, we had a decent number of winters where we received 20-30". But since 1987-88, we have had NO winters between 16" and 40". I feel like we are due, but I have been saying that for years now. I think there are a lot of factors at play, and I am hopeful that we will enter a snowier cycle soon. One thing that worries me, is what is happening in Richmond. Their snowfall norms used to be pretty close to ours, but they can't buy snow the past few winters. These huge shifts in norms have happened in other places like Portland and Seattle, so it can occur. Let's hope we don't become a city that averages single digits.
Alexandria, Va.: So many snow storms last year ran up the Appalachians. Has anything changed this year to stop that from happening again?
Matt Ross: Last winter we had a pretty strong La Nina event with anomalously cold waters in the Pacific ocean along the equator. And the winter acted like a typical La Nina, with a strong ridge of high pressure near Bermuda and a lack of blocking high pressure in the higher latitudes that allowed storm after storm to cut to our west, leaving us warm and rainy. While we are going to see storms cut to our west, I don't think that will be the prevalent storm track this winter. Look for more clippers and more coastals.
Falls Church, Va.: Hi, Matt. Do you see significant snowfall potential for mid- to late-December?
Matt Ross: Yes. I would be surprised if we don't see at least one 3-6" storm in December, and if the timing is right maybe bigger. Although we didn't break down snowfall by month, I think the bulk of our snow will fall in December and January.
Washington, D.C.: Hi Matt, how many days in advance do you think we can reliably forecast an individual snowstorm? I recall a number of times there was very little notice in advance of a big one.
Matt Ross: With models getting better and better, you can get the general idea of a pattern that "may" be favorable for DC snow 1-2 weeks out or more. But accuracy doesn't really get good until we are inside of 72 hrs or so and even then there are last minute fluctuations and surprises.
What was Tug Hill like? What were the snowfall rates?
Thanks and go snow!!
Matt Ross: It was great. I went for the big lake effect event in early February 2007. We saw 4-5"/hr rates at times. Lots of snowmobilers.
Sterling, Va.: I just want to know if it will snow around December 19. We have a long weekend vacation plan in Williamsburg, Va.
Matt Ross: Check back with Capital Weather Gang around a week before. If there is something brewing, we will be on it.
Okay, granted this isn't D.C. weather but here in my town, we're expected to get down to zero tonight -- this would be the earliest this has ever happened in decades. But I do have a question. Every time it gets super cold, the global warming naysayers cite this as "proof" that it isn't happening. Please correct me if I am wrong but isn't global warming a warming of the Earth's oceans, NOT the atmosphere, which in turn, causes crazy weather patterns? Thank you.
Matt Ross: I think a lot of red herrings get thrown into the Climate Change debate from both sides. I think you have to look at the big picture, and just because the earth is warming, doesn't mean we can't get periods of anomalous cold.
Bethesda, Md.: What are your thoughts on snow fall for Wisp Ski Resort this year?
Matt Ross: Wisp/Canaan Valley/Snowshoe are already getting good snow so far. I think Snowshoe has picked up almost 20" in the last couple days. I expect them to have a good season. I think Wisp averages about 100". I'd expect them to surpass that and have plenty of cold for snowmaking through January. February looks a bit warm to us, so they may go through some rough patches, but they should already have a good base to work off of.
non-snow question: Hi, Mr. Ross. My 5-year-old son loves to read the weather map on the back page of the Post's Metro section. Does this mean he'll be a meteorologist when he grows up? Are there any fun weather-related activities we should do with him? It's just funny to hear him talk about how it's going to be "partly cloudy" that day.
Matt Ross: My parents thought I would become a meteorologist too, and I became a lawyer, so who knows? Weather is a great hobby for kids. Your son sounds like he might enjoy a weather station at some point.
Maryland: Hi. Two things: first, thumbs up on your column/blog -- so much more content than the typical weather site, and interesting to boot! And second, we need a really good blizzard this year (enough so I can miss at least several days of work). What do you think?
Matt Ross: Big storms are one of those things you can't predict from the long range, especially around these parts. I do think we are ripe for a 6"+ storm in December or January. Hard to say whether it will be the "big one", but if cold air is in place, and the timing is right, 6" is enough to mess things up pretty good around here, or at least cause a run on milk and toilet paper :)
State of sunshine and palm trees: Matt Ross: "Yes. I would be surprised if we don't see at least one 3-6" storm in December, and if the timing is right maybe bigger. Although we didn't break down snowfall by month, I think the bulk of our snow will fall in December and January. "
With that being said, and the four million-plus people expected in Washington for Obama's swearing-in, can you see in your crystal ball, a catastrophic event as a snowfall on Jan. 19th, or starting Jan. 20th, that would shut down the metro and leave the four million people stuck, because our wonderful Metrorail can't operate in three inches or more and our Metro buses can't drive downtown due to the masses. What then?
Matt Ross: The Obama inauguration is going to be a big issue even if it is 50 and sunny. If there is a snowstorm, I can't imagine the stories. I am hoping after a string of presidents from warm states, that Obama will bring some of that Chicago cold and snow with him.
Ballston Spa, N.Y.: Any chance that you give forecasts for Tug Hill? I just moved up to upstate N.Y. from D.C. and enjoyed the CWG the past few months. Or, could you point me to a good local weather blog for upstate N.Y.?
Matt Ross: Easternuswx.com has a great weather forum with plenty of posters from Lake Effect Snow regions.
December or January snow?: So this 6+" storm you expect for December, can you narrow it down a bit? We're only two weeks away from December. Or do you mean closer to New Year's?
Matt Ross: Tough to say. As we see it, December will be a cold and exciting month for winter weather lovers. I think the potential is there throughout much of the month.
Bethesda, Md.: What would you say is the single biggest influencer on D.C. weather? The Atlantic ocean? The Chesapeake Bay? The Appalachian mountains? Something else?
Matt Ross: The Atlantic and the Mountains. Even though we are "latitudinally" challenged, the ocean allows us to get some rather big snowstorms that we wouldn't normally get at this latitude. The mountains rob us of a lot of moisture coming from the lakes, but they also help to keep cold air masses linger around at the surface for a lot longer than they normally would. It takes a while to scour out cold air when it is "dammed" up against the Appalachians.
Lake Ridge, Va.: How about the dreaded freezing rain/sleet scenario? What are the odds of us having this instead of "only" snow for the bulk of our winter "snow" chances?
Matt Ross: I am hopeful that sleet/freezing rain will occur less than in some recent winters, but no matter what the winter, precipitation type is always an issue here. So while I think the chances for a big ice event are a bit lower than in some previous winters, we are destined to see snow to rain, rain to snow, sleet events this winter.
McLean, Va.: Is there a distinct/typical line in this area of snow/sleet/freezing rain, or is all dependent on the storm and its track?
Matt Ross: It is obviously dependent on the track, but over and over again, I-95 seems to be the dividing line during borderline winter storms. All snow North and West of I-95 and mixing with sleet/rain south and east.
Manassas, Va.: Bob Ryan and Doug Hill always try to predict which days there will be snow. Any predictions?
White Christmas Day?
January? Hopefully not around the inauguration.
February? President's Day is usually a popular weekend.
Matt Ross: I'd say we have a better chance than usual at a White Christmas, but still less than 50-50.
Matt Ross: Thanks everybody for your great questions. My apologies if I didn't get to you. I know the numbers don't look very impressive, but after last winter, I think snow and cold lovers will have ample opportunity to be happy this winter. Hope it is an enjoyable winter for everyone.
Editor's Note: washingtonpost.com moderators retain editorial control over Discussions and choose the most relevant questions for guests and hosts; guests and hosts can decline to answer questions. washingtonpost.com is not responsible for any content posted by third parties.