Ski Weather - February 6, 2010
| 06 February 2010
It's been a busy week for meteorologists...Tuesday was Groundhog's Day, Friday was Weatherman's Day, and the week ended with a blizzard tagging portions of the mid Atlantic region. As was the case last weekend, strong high pressure over eastern Canada has served to suppress the storm to the south of New York State and New England.
From Pennsylvania southward to the resorts of Virginia and West Virginia, the snow is really piling up, and some resorts will end up with more than 30 inches from this storm. A new storm is going to roll through the Southwest this weekend, bringing fresh snow to the southern Sierra and the southern Rockies, while further north, any snow in the central and northern Rockies will be light this week. The Northwest, including the Olympic venues in British Columbia, will continue to be frustrated by the pattern, one that will keep snow levels relatively high, with only limited opportunities for significant snow. If you haven't taken a look at the discussion that was posted on 2/5 concerning the forecast for the 2nd half of the season, please do...we are entering what promises to be a remarkable stretch of weather in the eastern half of the country and it is all broken down for you there. In the shorter term, the mid Atlantic "mauler" will be followed by another significant storm in just a few days, and this time, I think the snow will be spread further north into New York and New England.
Let's take a look at today's jet stream map...
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The two primary features on this map will figure prominently in the production of snow over the next 4-5 days. The first is the closed upper low centered over the Chesapeake Bay region...that is supporting a surface low just off the coast, and the combination is dumping the heavy snow in the mid Atlantic. The trough that is stretched out from the waters west of Washington down to southern California is the other major player. The southern half of that trough will be stronger than the northern extension because the northern piece will run into the ridge sitting over western Canada, but you can see that there is a much weaker ridge, providing much less resistance, over the central and southern Rockies. As a result, the mountain ranges of the Southwest can expect a nice shot of fresh snow, on the order of 1 to 2 feet; by the time we reach the week of the 8th.
When the southern branch system moves out onto the Plains, it will spread a swath of snow from west to east right through the heart of the country. Meanwhile, the "X" that you see several hundred miles north of the Minnesota/Canada border denotes a short wave trough that will be a big player in the next storm. That short wave will move southward and strengthen this weekend, and by early next week, it will be an intense closed low over the Dakotas, and it will be turning southeastward at that time. Right now, it looks as though it will interact with the southern branch system, and the result will be an impressive upper low close to Detroit by Tuesday night. One surface low will be cranking out snow in the Ohio Valley and lower Great Lakes, and as the upper low translates eastward, a secondary low will form somewhere along the coast...probably east of Atlantic City, and that low will become the primary storm rather rapidly. Snow will fall throughout the Northeast, with the heaviest amounts likely to pile up in New York and New England. Amounts in the Catskills, Adirondacks and the mountains of New England could easily exceed a foot with this storm.
In the wake of the midweek system, cold air will continue to dominate until further notice in the Lakes, mid Atlantic, and Northeast. Packed powder has made an incredibly fast comeback in the wake of the rainstorm of January 25th, and soft dry snow will be found in abundance in the East throughout February. The Southwest will continue to receive their fair share of fresh snow in the near future, but the Northwest will have to make do with the occasional light snow event that wanders in off the Pacific. The resorts of the Great Lakes will stay a little colder than normal, and their fresh snow will come from Alberta Clippers that move southeastward on their way to dancing with the southern branch...the Clipper coming through this week is a strong one, and it should produce a nice shot of snow for many resorts in the upper Midwest. The big winner in this winter's snowfall sweepstakes will continue to be the mid Atlantic and Southeast...they have enjoyed more powder days this year than they have in the past 5 years combined, and the parade of storms is far from over! The overall pattern has been incredibly persistent for much of this winter; with an eastern ridge in place much of the time, complemented by a western upper ridge. All indications are that the pattern will remain persistent for many more weeks. (You can see all of the reasons for that forecast if you check out the 2nd half forecast discussion).
REGIONAL SUMMARIES:
NORTHERN ROCKIES/NORTHERN COASTAL RANGES/WESTERN CANADA
With a ridge at the upper levels parked over western Canada and extending down into the central Rockies, these regions will have a rather quiet week. A possible exception will be just to the east of the Continental Divide, where the western fringe of the cold air associated with the strong short wave diving through the Dakotas early in the week will mix with some modest pacific moisture to produce a moderate snowfall in portions of Wyoming and Colorado. Elsewhere, some Pacific energy will attempt to dent the west ridge later in the week, resulting in some light snow in the Cascades prior to the weekend of the 13th/14th.
SOUTHERN COASTAL RANGES/SOUTHWEST
Another sizable storm will move through this region between the 6th and the 8th, and it will have enough moisture to crank out amounts of 1 to 2 feet in the mountains from central and southern California eastward to the resorts of southern Colorado and New Mexico. Additional jet energy will bring renewed snows during the weekend of the 13th/14th, before a large-scale ridge builds throughout much of the West around the week of the 15th.
CENTRAL ROCKIES
A predominantly zonal, or west to east jet stream flow will dominate much of the next week in this region. The resorts of northern Utah and Colorado will catch some light snow from the northern fringes of the system moving through the Southwest over the next few days, but a major snow event is not in the cards for the foreseeable future. The western edge of the strong short wave moving through the Dakotas early in the week will help set off some light snow along the front range.
UPPER MIDWEST
Cold and relatively dry weather will continue to rule this region until further notice. A strong short wave/Alberta Clipper will move through the region early in the week, and although it will be short on moisture, its dynamics will enough to crank out light out moderate amounts in the northern Great Lakes and northern Plains. Some lake effect snow will fly in the wake of the passage of the short wave. Additional Clipper systems will move through every few days until further notice, as the northwesterly flow remains firmly entrenched.
MID ATLANTIC/SOUTHERN APPALACHIANS
Simply put, these areas are enjoying their best snow year in memory, and all indications are that the hits will just keep on coming as long as the southern branch remains active and the cold air keeps coming southward. All indications are that just such a pattern has many weeks to go yet.
NORTHEAST/EASTERN CANADA
As I suggested at the start of the season, there would be periods when cold, dry air and high pressure would be too much of a good thing, acting to keep the storm track too far south to be beneficial. That has been the case for the past three storms, but a subtle change in the blocking pattern over the north Atlantic will allow the next system to form further north and impact resort in New York and New England that have been a bit snow-starved of late. A weak short wave will bring some light snow to northern New York and northern New England late this weekend, but it is the midweek storm that should set things up very nicely for the coming February vacation period. The weekend of the 13th/14th holds some promise for another coastal storm, and the pattern will remain conducive to enhanced storminess until further notice.
