Maybe it should increase our confidence in the National Weather Service to know that, months ago, the Blacksburg office picked the perfect weather weekend to have its every-two-years open house. The event will run from 10 a.m. to 3 p.m. Saturday at the weather service’s office in the Corporate Research Center. If you’re traveling U.S. 460, turn on Southgate Drive toward Lane Stadium, then take a right at the intersection near Lane Stadium on Tech Center Drive, and the weather service is to the right just past where the road curves around the west end of the Virgina Tech Montgomery Executive Airport. If you’re there between 11 and 2, stop by the Virginia Tech Storm Chasers exhibit outside and say hi — I plan to be there during that timeframe. Guest blogger Kathryn Prociv – due for another 3-day stint here next week, fresh off her first appearance on the Capital Weather Gang site — will also be around. And of course there will be many other exhibits, plus tours of the weather service office and a chance to meet the people behind the forecasts and warnings and discussions we so often examine on this site.
Temperatures have started November in the tank compared to normal — 8 to 10 degrees below normal at Blacksburg and Roanoke, with mutliple mornings below freezing. Strong high pressure blocking near Greenland has forced the jet stream far to the south, the “trough” carved out more last week of the slowly weakening but widening circulation of Superstorm Sandy. This pattern also spawned a strong early season nor’easter that dumped up to 13 inches of snow along and just inland from the coast of the Northeast. But the pattern is now relenting. The next couple of mornings will continue to be chilly — below freezing in much of Southwest Virginia — but by Saturday afternoon there could be some low 70s, especially from Roanoke south and east, with 60s just about everywhere else in Southwest Virginia. With a low-pressure trough digging into the West instead of the East, and the upstream blocking high in Greenland breaking down, much of the weather action will shift to the central U.S. A strong low in the central U.S. will unleash heavy snow on the central and northern Rockies, extending into the northern High Plains, with blizzard conditions possible. This low will move northeast into Canada and drag a cold front through our region about Tuesday of next week, bringing some showers and a cooldown, maybe a couple of days of 40s-50s highs/20s-30s lows chill. But the pattern appears likely to bounce back to mild-mannered by late next week. There is an interesting storm system showing up on the models round the weekend before Thanksgiving — interesting in that it could be a strong southern-stream system wrapping up in the Southern Plains, something we haven’t seen much of at all since the 2009-10 winter. The early models show a significant cold-air damming signal east of the mountains, but not really much cold air available to dam, with the current blocking pattern not present to force Arctic air south. I’m not expecting this storm to become a significant wintry precipitation maker in our region — probably a holiday week rain maker — but it may signal the growing influence of a southern jet stream branch, a feature that could make our winter wetter and/or whiter, if it duplicates frequently. Its passage may also reset the pattern to something colder by late month or early December, though this is very iffy at this point.