Wednesday, December 7, 2011

Major Storm Opens December 2011


Town of Wise
December 7, 2011
Decorated For The Holiday Season
Photograph by Roddy Addington - © All Rights Reserved.


A fast & furious fall of heavy snow capped off yet another major storm to close the first week of December 2011 and begin meteorological winter.

Elevation 2454 feet
Afternoon of December 7, 2011
Winter Majesty In The Town of Wise
Photograph by Roddy Addington - © All Rights Reserved.

It was a scene of pure beauty in Wise where Holiday decor was perfected by Mother Nature's furious afternoon burst of heavy snow.

December 7, 2011
Winter Wonderland On Wise Plateau
Snow Sticking To Power Lines In Wise Despite Wind
Photograph by Roddy Addington - © All Rights Reserved.

A general 2" to 4" of snow accumulation was reported across the Norton-Wise area during the afternoon.

It should be pointed out that this fast hitting event produced some interesting effects, as despite wind that blasted snow onto poles it still managed to stick to overhead wires amid the quick switch from drenching rain to heavy, wet snow.

December 7, 2011
High Chaparral of High Knob Massif
Heavy Snow, Wind, And Low Clouds
Photograph by Darlene Fields - © All Rights Reserved.

A few air miles south of Wise conditions got BAD amid the High Knob highcountry, with strong N-NW winds and near whiteout conditions above 2700 feet, as well documented by Darlene Fields.

Elevation 3300 feet
High Chaparral of High Knob Massif
WIND Blasted Trees & Snow Covered Roads
Photograph by Darlene Fields - © All Rights Reserved.

Snow was blasted onto trees from bottom to top as roads gradually disappeared beneath the furious fall to create surreal looking scenes amid icy clouds of wind driven flakes.

Afternoon of December 7, 2011
Remnant Massif of the High Knob Landform
Beautiful Mid-Afternoon Darkness In The Highcountry
Photograph by Darlene Fields - © All Rights Reserved.

Observe how snow was drifted up around tree trunks in the above scene, amid an eerie looking afternoon darkness of the deep woods.

December 7, 2011
Lower End Snow Depths In High Chaparral
Photograph by Darlene Fields - © All Rights Reserved.

As heavy snow began to wane it left snow depths that varied from 2" to 3" on the lower end of the measuring stick to as much as 6" on the higher end, with larger drifts.

December 7, 2011
High Chaparral of the High Knob Massif
Half A Foot of Snow Depth On The Ground
Photograph by Darlene Fields - © All Rights Reserved.

On the main summit, above 4000 feet, it was a different story as the sustained winds were so strong that they literally swept highly exposed places nearly bare!

December 7, 2011
Wind Swept Gap Between High Knob & Eagle Knob
Photograph by Roddy Addington - © All Rights Reserved.

That is actually a great stop motion shot by Roddy as upon close inspection one can see large snowflakes that are moving sideways and even UP in direction.  Look in particular along right side of picture as those cotton-like blobs are snowflakes moving UPslope across the lofty summit!

The above is why it is sometimes nearly useless to measure precipitation along these highly exposed convex crestlines that face winds, as precipitation elements ( including rain ) not only move horizontally but also vertically in direction when upslope forcing is strong.

Elevation 4100 feet
Bitter Cold Fury & Low Visibility 
Wind Blasted Along The Crest Zone
Photograph by Roddy Addington - © All Rights Reserved.

Looking from High Knob along the lee side of Forest Service 238 much deeper snow can be seen in the above photo by Roddy taken along the southeast slope of Eagle Knob.

So where does all that snow go?  If one looks around it typically can be found along lee sides of ridges, in drifts, and even in this setting over into the lofty High Knob Lake Basin!

December 7, 2011
Near Summit of High Knob Peak
Wind Sculpturing Around Large Rock On Ground
Photograph by Roddy Addington - © All Rights Reserved.

On small scales one can also see the same type of effects around objects on the ground, like this rock Roddy photographed above with much more snow on one side than the other.

[ Not a truly ideal example above since both sides of this rock were exposed to 30-40+ knot winds, as Roddy well verified and felt in middle 20s air temps that blasted him & the ground. Ouch! ].

Elevation 3300 feet
High Chaparral of High Knob Massif
Snowboard Adjacent To 5-6" Ground Depths
Photograph by Darlene Fields - © All Rights Reserved.

A very good way to measure snow and to determine how much new snow falls once the ground becomes covered is to use snowboards, placed on or above ground in various locations.

The above method being detailed nicely by 
The Snow Booklet of Colorado State University.

Picnic tables, or other types of above ground objects which are not going to be moved during an event, can also make good measuring boards.

December 7, 2011
High Chaparral of High Knob Massif
Outdoor Picnic Table Used As Snowboard
Photograph by Darlene Fields - © All Rights Reserved.

A key feature of this method being to measure and sweep the boards clean once every 6 hours, ideally, that snow is falling ( with four but not more than four measurements during a 24-hour period ).

December 7, 2011
HUGE Flakes In High Chaparral of High Knob Massif
Photograph by Darlene Fields - © All Rights Reserved.

Another notable feature of this event was huge snowflake sizes, especially during intervals where strong winds decreased just a little.


Winter Storm Along 
The Tennessee Valley Divide

December 7, 2011
Heavy Snowfall On Long Ridge At 4:23 PM
Photograph by Genevie Riner - © All Rights Reserved.

My friend Genevie Riner documented the fury of this snowstorm as it engulfed the high ridges along the Tennessee Valley Divide.

December 7, 2011
Heavier Snowfall On Long Ridge At 4:40 PM
Photograph by Genevie Riner - © All Rights Reserved.

Given soaking rains which fell through morning hours it was rather shocking to see how fast snow was able to stick to everything!

Afternoon of December 7, 2011
Rapid Transformation Into Winter - Snowfall & Wind
Photograph by Genevie Riner - © All Rights Reserved.

Accumulations became significant, with an official storm total of 4.6" being measured by Genevie & Wayne Riner at Nora 4 SSE ( elevation 2650 feet ).

December 7, 2011
Snow Piling Up Amid Fury Of Storm At 4:54 PM
Photograph by Genevie Riner - © All Rights Reserved.

Clearing skies into December 8 created simply gorgeous scenes on the high ridges.

December 8, 2011
Long Ridge of Sandy Ridge of the Tennessee Valley Divide
Heaviest Snow Of Early Winter Along The High Ridges
Photograph by Genevie Riner - © All Rights Reserved.

Observe how thick snow has stuck to trees amid folds of the terrain, beneath ridges, while those trees exposed are mostly bare to create striking contrasts in the morning light!

Morning of December 8, 2011
Looking Along The Tennessee Valley Divide
Photograph by Genevie Riner - © All Rights Reserved.

Genevie captured an interesting scene in this next photograph as a rather distinct morning inversion layer had developed, denoted by the sharp cloud line below, with warming temps amid a zone from around 3500 to 6500 feet that trapped moist air near the surface.

Morning of December 8, 2011
Long Ridge of Tennessee Valley Divide
Top Of Inversion Layer - View Toward Pine Mountain
Photograph by Genevie Riner - © All Rights Reserved.

Although morning minimums dipped into bitter mid-upper 10s across much of the snow area lying above 2200 feet in elevation, the presence of upslope cloudiness throughout the night beneath this inversion layer kept temps from getting even colder over the fresh snow cover ( the inversion mixing out over higher terrain after sunrise but still visible in the far distance, mostly beyond Pine Mountain, toward the Kentucky foothills ).

December 8, 2011
Feeding Time In The Highlands - After A Bitter Night
Photograph by Genevie Riner - © All Rights Reserved.

Mountain ridges & plateaus form many nice communities across Dickenson and Wise counties, with elevated farms that plunge off into deep, twisting hollows.

Snow cover always acts to accentuate the terrain, with every wrinkle & fold becoming visible across this amazing landscape of the southern Appalachians!



First Significant
December Precipitation Event
( December 5-7, 2011 )

December 7, 2011
Standing Water Surrounded By Snow
Photograph by Isaiah Addington - © All Rights Reserved.

Isaiah Addington ( Roddy's son ) captured the major aspect of this event by showing standing water from yet another big precipitation maker that generated strong rises on creeks and rivers.

My friend Andrew Greear measured a total of 2.41" at the Norton Water Plant, with around 0.37" of that being in the form of wet snow, boosting the 2011 tally to 73.24" for the City of Norton.

My friends Otis & Nancy Ward had a precipitation total of 2.55" in the Robinson Knob community of the High Knob Massif, boosting 2011 to 78.29" and their 12-month total to 82.12" ( despite substantial missing gage moisture in deep snows last winter ).

River Rises 11.86 Vertical Feet
River Gage Height At Speers Ferry In Scott County

Run-off from much of this precipitation generated another huge rise on the Clinch River with nearly 12 vertical feet of total increase being observed at Speers Ferry in southern Scott County. 

[ Note that a general 0.30" to 0.60"+ of moisture was locked away in snowfall which reduced run-off during this event ].


Wonderland In Lights
Camp Bethel In Wise, Virginia
December 7, 2011

Magic Of The Holiday Season - Camp Bethel In Lights
Photograph by Roddy Addington - © All Rights Reserved.


Roddy took time to capture the holiday season with a drive out to always beautiful Camp Bethel, resting upon 160 acres on the Tennessee Valley Divide of the Wise Plateau.

The lake at Camp Bethel is only 3.5 air miles north of the northern-most base of the High Knob Massif, near Ramsey, and is approximately 6.6 air miles north-northeast of the Dam at Upper Norton Reservoir.

Lake Elevation of 2520 feet
Snow Adds To Holiday Beauty At Camp Bethel
Photograph by Roddy Addington - © All Rights Reserved.

Several inches of snow added to the beauty of this magical scene by the lake at Camp Bethel, with tree bows hanging low under the high density snow.

December 7, 2011
Beautiful Snow At Camp Bethel
Making Kids Jealous In The Tri-Cities
Photograph by Roddy Addington - © All Rights Reserved.

Scenes such as these no doubt make many kidos, and "grown-ups" too, jealous who missed out on significant snow accumulations in the Tri-Cities to Knoxville corridor of the Great Valley.

Camp Bethel in Wise
Sugar Canes & Snow - Dream Come True
Photograph by Roddy Addington - © All Rights Reserved.

With such strong NW-N winds pushing into windward slopes of the High Knob Landform and higher portions of the Tennessee Valley Divide it is no wonder that sticking snow was hard to come by in the Tri-Cities, given such air trajectories add warming & drying to low-levels of the atmosphere.

NASA Visible Satellite Image At 9:31 AM - December 8, 2011
Image Courtesy of the Earth Science Office

Snow on visible imagery tends to show up best over flatter, more open terrain.  The rolling farms of both Russell & Tazewell counties show up better than their higher mountain ridges.

In the High Knob Landform, a narrow stripe of snow is visible along Wallen Ridge to the Buzzard Roost where it abruptly ends in northeast Lee County.  The crestline of Cumberland Gap NHP is faintly visible along the stateline above far western Lee County.

The crestline of Little Stone and Stone mountains is also visible to just past Cave Springs Wilderness Area, with the inverted V-shape of Powell Valley in Wise County being completed by the bulge of the High Knob Massif to the southeast and the capped crestline of its Little Stone Mountain arm toward the northwest.

Some of the white on this image is clouds where gravity waves are visible across northern portions of West Virginia & Virginia. Wavy cloud streets are also seen where cold air flows over the Atlantic.

Note the abrupt cut-off on snow visible in the above image south of northern Scott County where air flow plunges downward off the highcountry of the High Knob Massif.

The southwest extension of snow visible through Russell County is northeast of the downsloped forced shadowing zone leeward of the massif on N to NW air flow trajectories.

NAM Model 850 MB Chart At 7 PM - December 7, 2011
Image Courtesy of NCEP Central Operations

This is illustrated by the above chart where air flow above the boundary layer of Earth tends to run parallel to the black isobars, or lines of equal pressure ( north to south flow in this case ).

At the surface, by contrast, drag of air flowing across the terrain generates friction that forces a cross-isobaric turning of the wind field as illustrated by the NW wind vector arrows.

The result of these two factors was a strong N-NW air flow crossing the High Knob Massif, with general 3" to 6" snow depths along its windward slopes verses little to no sticking snow leeward of the massif on downslope forced drying & warming. 

[ Renewed lifting by the secondary front range along the TN-NC border, with respect to NW air flow, was required to generate enough cooling to deposit snow once again ( leaving much of the Great Valley devoid of snow accumulations ) ].

Beautiful Camp Bethel in Wise
Lollipops & Snow - Could It Get Any Better?
Photograph by Roddy Addington - © All Rights Reserved.

My friend Darlene Fields captured numerous nice scenes as she came down out of the highcountry toward Tacoma, along State Route 706, during December 8.

Along Stone Mountain Road ( State Route 706 )
Winter Beauty Near Stone Mountain Church
Photograph by Darlene Fields - © All Rights Reserved.

Snow stuck best to trees in sheltered places such as high hollows, coves, and lower portions of the mid-elevation zone where wind speeds were not as strong ( as illustrated on Long Ridge ).

Along State Route 706 in Wise County, Virginia
Canadian Hemlock ( Tsuga canadensis ) Bows In Snow
Photograph by Darlene Fields - © All Rights Reserved.

It was a winter wonderland drive along scenic Stone Mountain highway, State Route 706, with thick snow on trees in sheltered places.

December 8, 2011
Winter Wonderland Drive - High Knob Massif
Photograph by Darlene Fields - © All Rights Reserved.

Snow depth decreased into lower elevations, but it looked pretty sticking to trees and bushes against the blue sky of December 8.

December 8, 2011
Lower Elevations Above Tacoma Valley
Photograph by Darlene Fields - © All Rights Reserved.

A little different from half a foot of depth to add more interesting variety to this already amazing mountain landscape!

High Knob Massif during December 7, 2011
Half A Foot Of Ground Depth - High Chaparral
Photograph by Darlene Fields - © All Rights Reserved.

Speaking of which, check out this latest video production by my friend Richard Kretz who highlights many wonderful attributes of 


Southwest Virginia: 
One Of The Last Great Places On Planet Earth!

Produced & Directed by Richard Kretz


A fantastic overview of biodiversity in the Upper Tennessee River Basin of southwestern Virginia.  Thank you my friend!


[ *Note: A link to this video can always be found along the right column of this website under Richard's name and email address ].

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