top border

Please note, not all links may be active. This site is a snapshot of an earlier time.

Windy, Sunny, Chilly: Spring at-Bay this Friday

A. Camden Walker @ 2:02 AM

Forecast: Wind Wins


Click for more information on Kevin Ambrose's photographyDespite lots of sunshine today, the wind will blow over 20mph at times and make you doubt it is even in the 40s. Expect even the coldest suburbs experiencing 30 degrees at sunrise to touch 47 degrees late this afternoon.

Those of you directly along and west of the Blue Ridge without the downsloping wind "warming benefit" will stay in the lower 40s. We'll all get blown around today, and a scarf might be needed at times. Drive carefully and beware the "Venturi Effect"[at link's bottom] between urban buildings if you are walking around Metro Center.
Forecast looks simple after the front moves through at dawn!

February 23, 2006: Crepuscular rays over a large cumulus cloud that produced a rain shower in Reston, VA - Click photo for more information on CapitalWeather.com photographer Kevin Ambrose.

Snow Lover's Crystal Ball
Next Chance of Accumulating Snow: Tuesday, Feb. 28
Probability: 25%
Potential Impact:
Commentary: A very weak Alberta Clipper moving into our region after midnight Monday may spread light snow during the pre-dawn hours Tuesday.


FRIDAY FEATURE
Chesapeake Bay-effect Snow: Our Region's Rare Snow Machine

January 10, 2004 radar image
We've all heard of Lake-Effect Snow which impacts the snow belt regions of the Northeast & Great Lakes region. However, our Washington-area Chesapeake Bay is prone to produce snow bands, on average, every few years!

With the Bay's longest stretch of water oriented meridionally (north to south), the most favorable wind direction is north or north-northwest--resulting in a localized risk of snow accumulation around Hampton Roads, Virginia. Traditionally known as an epicenter for these snow events is Kent Island, VA.

Many bodies of water around the world produce local snow events. All it takes is large-scale ("synoptic") wind patterns that favorably align along the longest portion of a water body that is adjacent to land. If a storm system is already producing precipitation as it moves through the area creating favorable wind direction, an "enhancement" situation augments this pre-existing precipitation. The Hampton Roads area receives "Bay-enhanced" precipitation when a low pressure system approaches the area slowly and in an exact manner, from the southwest.

Of note is that snow isn't always necessarily the sole precipitation type that results from water body-events. In the summer, cold air from Canada can give Buffalo, Syracuse, or Cleveland bouts of cold rain when this air moves across warm lake waters. If these same Great Lakes waters are completely frozen over in the coldest portion of Winter--fetches of wind have no moisture source as they benignly blow across the lakes--resulting in barely a cloud developing (yet alone snowfall).

Cross-section of water body-created precipitationIn either a Lake/Bay-effect or Bay-enhanced weather event, cold (polar/arctic) air travels across a water body, picks up heat and moisture, and is destabilized. Cloud formation is enhanced by thermal and frictional convergence and upslope along the lee shore of said body of water.

Below is a graphical depiction of "local" (North American) areas prone to precipitation events from water in-proximity:
  • "Lake-effect" (Great Salt Lake, NY Finger Lakes, U.S. Great Lakes)
  • "Bay-effect" (Chesapeake, Delaware, Massachusetts Bays)

    Now that you are in the know on Chesapeake Bay snow, would you think it wise to build a ski resort where these folks decided to build five years ago? Bay-area Baltimore doesn't receive the Bay-effect snow on which these owners seem to have pinned many hopes. Leg Pullin of The American Ski and Upholstery Company states this as a partial expectation, mid-way through the article. Are there even many hills between Baltimore and the Bay?? Interestingly, I can't give you an NYSE chart/quote on ticker "ASUC" -- perhaps my attempt to check the company's pulse turned up a delisting on the exchange.

    Globalization, if it is impacting the ski industry, might look to internationally outsource to areas such as Japan?...or Finland?
    • "Ocean-effect" (North America's Gulf Stream, Sea of Japan)

    • "Gulf-effect" (Gulf of Finland near Estonia, Finland, & Sweden)

  • Comments are closed for this archived entry | Link | email post Email this post