Tuesday, January 3, 2012

Arctic BLAST & Heavy Snow Opens 2012


Afternoon of January 2, 2012
Crest Zone of High Knob Massif
Snow Deepens Between WHITEOUTS ( 3" to 4" )
Photograph by Roddy Addington - © All Rights Reserved.

The High Knob Landform

An intense band of snow squalls generated WHITEOUT conditions in the High Knob Massif amid a furious, wind driven passage of an arctic cold front during afternoon hours of January 2.  

Morning flurries gave way to snow squalls in advance of the arctic front whose approach was foreshadowed by increasing wind and a eerie darkening of skies into night-time like blackness prior to its ferocious strike!

Crest Zone of High Knob Massif
Along Forest Service 238 - January 2, 2012
Subsidence Induced Break In Upslope Clouds
Photograph by Roddy Addington - © All Rights Reserved.

Photographer Roddy Addington was in the High Knob highcountry capturing these awesome scenes along with his friend & fellow photographer Bill Harris.

It would prove to be a fun 
but very dangerous adventure!

Sinking air in the wake of this potent arctic front was strong enough to even open holes up in clouds over the massif, with both pre-frontal and post-frontal clear intervals observed as the arctic boundary passed across lower elevations of Dickenson County.


Arctic Cold Fronts
And Mountain Snow Squalls!

January 2, 2011 ( Near 4200 feet above sea level )
A Developing Whiteout - Eagle Knob of High Knob Massif
Photograph by Roddy Addington - © All Rights Reserved.

It was already bitter before the actual arctic front ever arrived with air temperatures in the 10s on Eagle Knob of the High Knob Massif, and wind chills that made Roddy's hands sting while taking pictures ( chill factors were already going sub-zero )!

JKL Doppler Base Reflectivity at 2:09 PM - January 2, 2011

Climatology dictates that arctic cold frontal snowbands often form along the leading edge of -12C 850 mb temperatures, which forecast models projected to be just west of the Virginia-Kentucky border by 1:00 PM on January 2.  By 2:09 PM a band of intense snow had developed and was crossing the stateline to mark it.

Remnant Massif of the High Knob Landform
In A WHITEOUT - Afternoon of January 2, 2012
Photograph by Roddy Addington - © All Rights Reserved.

Snow squalls can be beasts in the mountains where upslope drives air upward to support their vertical motion.  When the arctic front hit Roddy said 1.5" of new snow accumulation occurred in only 10 minutes!

NASA Visible Imge at 2:31 PM - January 2, 2011
Image Courtesy Of The Earth Science Office

An enhanced upward bulge of clouds are seen on NASA visible imagery at the time intense snow fell upon the High Knob Massif
( note Wise-Scott County, Va., border ) in association with this arctic boundary.  Also observe the arch of clearing behind it over the Kentucky foothills as subsidence ( sinking air ) occurred in the wake of this zone of upward motion ( rising air ).

Arctic fronts can lose their identity leeward of the western front range of the Appalachians as low-level convergence weakens; however, that is typically not the case along and northward of the High Knob Massif where MANY intense passages have been well documented by climatology.

The above being especially the case with NW flow driven arctic fronts where moisture extraction leeward of the western front range of the Appalachians is most pronounced, with low density snow acting to enhance the effect downstream of wide mountain masses like the High Knob Massif.

Arctic Fronts pushed by SW to W air flow trajectories can often, by contrast, sweep more strongly into the typically snow starved Great Valley of the Appalachians.

 This description applies to snow squalls in general, 
with snowstreaks being a marked exception as one 
squall after another moves over a narrow corridor 
with little to no break in between downpours for
a much longer period of time ( sometimes for hours ).

A classic pattern occurs as arctic fronts and/or snow squalls
form over the mountains.  It goes something like this...... 

Flurries develop.
  
The sky grows increasingly dark with
a notable increase in wind.
  
Flakes start to fall with more vigor and
may change form and size. 

If during the day, an almost night-like darkness develops as distant ridges 
vanish from sight!

Snowfall increases and wind stiffens.

Then suddenly, if not paying close attention, a swirling mass of blinding flakes arrive on a ROAR of wind driven fury that engulfs every nook & cranny ( big & small )!

Its a major WOW!


A mini-BLIZZARD has formed
( sometimes with lightning & thunder ).

It may last 5, 10, 15 minutes or even longer and reduce visibility to essentially zero, quickly coating everything in whiteness!  Skies brighten as snow continues to POUR.  Snowflake forms and sizes tend to change multiple times during the event until sinking air in its wake compensates for all the upward vertical motion to finally overwhelm low-level convergence.  Snowfall diminishes and skies may become blue ( at least temporarily ) with sunshine by day and stars by night!

Its a rather glorious atmospheric process
( unless you become stranded along a highway or worse! ).

Afternoon of January 2, 2012
Fury of Snowflakes On Eagle Knob
Photograph by Roddy Addington - © All Rights Reserved.

This period of intense snow generated some interesting scenes, such as this tree trunk with a precise line of blasted snow!

January 2, 2012
Eagle Knob of High Knob Massif
Amazing Line Of Snow Blasted Onto Trunk
Photograph by Roddy Addington - © All Rights Reserved.

The snow appearing to have accumulated via an enhanced rush of air flow as it was funneled between the tree trunks.

This Christmas Fern ( Polystichum acrostichoides ) that managed to stay just above the deepening snow.

High Knob Massif - January 2, 2012
Christmas Fern In Wake Of Heavy Snow
Photograph by Roddy Addington - © All Rights Reserved.

And this former warm season wildflower ( below ) that held delicate snow despite the furious nature of this wind driven fall.

High Knob Massif
Clinging To Snow In Arctic Blast - PM January 2
Photograph by Roddy Addington - © All Rights Reserved.

Mostly this arctic fury left a majestic highcountry landscape of beautiful scenes, with off and on snow showers that would again become intense into the upcoming night on NW upslope flow!

January 2, 2012
High Knob Massif Crest Zone
Bitter Cold In Wake Of Afternoon Arctic Front
Photograph by Roddy Addington - © All Rights Reserved.

Always amazing how some trees can hold snow
amid such strong winds.

January 2, 2012
Above 4000 feet In The High Knob Massif
Photograph by Roddy Addington - © All Rights Reserved.

This event started another prolonged period of snow cover for lofty High Knob Lake Basin, with 22 days of 1" or more of depth and counting for the season ( as of January 3 ).

Head of Mountain Fork of Big Stony Creek
Jefferson National Forest Special Biological Area
High Knob Lake Basin - PM January 2, 2012
Photograph by Roddy Addington - © All Rights Reserved.

As often is the case, note how snow depth looks greater in this area as strong winds blow snowfall across high crestlines into this lofty basin ( and adjacent basins of the massif ) as I have well documented many times in past years with ruler measurements.

January 2, 2012
High Knob Lake Basin
Breaks In The Overcast Amid Fluffy Flakes
Photograph by Roddy Addington - © All Rights Reserved.

Late afternoon breaks in the overcast hid the fact that more intense snow was soon to develop!

Water Elevation of 3308 feet
Benges Basin of High Knob Massif
Majesty Of Upper Norton Reservoir - January 2
Photograph by Roddy Addington - © All Rights Reserved.

Having done a 180 degree spin around in the road during this trip, the beauty of Upper Norton Reservoir was purely a welcomed sight on this frigid January afternoon.

Some of the most winding roadway is actually below the Upper Norton Reservoir, heading downward into the City of Norton, so its no "picnic" drive from here either in the winter season!

As Roddy stated so well...
" If you messed up today up there 
you could have died real easy!"

What most viewing these awesome scenes do not realize is how harsh this massif gets during winter and how dangerous it becomes for the many residents, U.S. Forest Service workers, Eagle Knob workers, Water Plant workers, hunters, and folks like Roddy, Bill, and even myself that travel across it during such times. 

I thought certain that I was a "goner" upon doing a complete spin on a icy, snow covered road adjacent to a simply HUGE vertical drop.  Only by luck and the grace of God did my vehicle spin in the "right way" to avoid nearly certain death.  This is NOT a place to take for granted ( in more ways than one says this website ).

PM of January 2, 2012
High Chaparral Snow In Wake Of Arctic Squalls
Photograph by Darlene Fields - © All Rights Reserved.

Miles to the southeast of Upper Norton Reservoir, Darlene Fields measured 3" of snow depth in wake of these initial arctic squalls 
( 1" less than the main crest zone ).

Having lived in the High Chaparral community of the High Knob Massif for decades, both Darlene and husband Joe have also had accidents during winter on roadways in this mountain mass ( as most do in one form or another over time ).

Elevation 3300 feet
High Chaparral Snow Depth at 5:15 PM - January 2, 2012
Photograph by Darlene Fields - © All Rights Reserved.


Snowstreaks And
NW Upslope Snowfall
( Evening of January 2 into AM of January 3 )

Elevation 4189 feet
Eagle Knob of High Knob Massif
Conditions Inside Snowstreak On Eagle Knob at 10:23 PM
Photograph by Steve Blankenbecler - © All Rights Reserved.

The evening of January 2 turned wicked in the crest zone of the High Knob Massif, with a very well developed snowstreak streaming across the upper portions of Powell Valley into heads of lofty Big Cherry Basin, High Knob Lake Basin, Benges Basin, and adjacent smaller basins joining main crestlines in the massif.

Additional snow squalls and snowstreaks also made conditions bad in other sections along the Virginia-Kentucky border.  The High Knob Massif snowstreak being most intense, buoyant, and long-lived, streaming into Tennessee & decreasing downstream.

JKL Doppler Reflectivity at 10:26 PM - January 2, 2012

While this snowstreak remained just west of the High Chaparral community, it impacted portions of the City of Norton with heavy snow, temps in the low-mid 10s, and bitter wind chills.

Conditions 2000+ vertical feet above the City of Norton were brutal, with single digit air temperatures and sub-zero wind chill factors in near zero visibility.

January 2, 2012
NASA Color Enhanced Infrared Image at 10:32 PM
Image Courtesy Of The Earth Science Office

A Great Lake moisture connection was helping support the activity in combination with extremely cold air aloft in upper levels and upsloping WNW-NW winds at low-levels.

Temperatures as cold as -35 to -40 degrees ( Fahrenheit ) below zero were centered around 17,000 feet to generate steep vertical lapse rates despite relatively bitter air at the surface.

The snowstreak being aided by nearly unidirectional 850-700 mb flow trajectories from the Great Lakes of Superior & Michigan ( see later graphics ).

Once evening snowstreaks dissipated a transition into a general and widespread NW upslope flow snowfall event was observed into January 3.

Elevation 3300 feet
Early Morning of January 3, 2012
New Overnight Snowfall In High Chaparral
Photograph by Darlene Fields - © All Rights Reserved.

Despite missing the snowstreak, Darlene Fields measured 3" of new overnight snow depth with NW upslope flow in High Chaparral.

Snow Depth On Settled Snow - AM January 3, 2012
Photograph by Darlene Fields - © All Rights Reserved.

Mean depths of around 6" were measured by early morning hours of January 3.

Given settlement on the low density, fluffy snow and additional snow falling into afternoon hours of January 3 the final storm snowfall total reached 7.0" in High Chaparral.

Some 1,000 vertical feet lower in elevation, amid the City of Norton, Joe Carter measured 0.22" 
of water content in their NWS rain gage for snow falling in the 24-hour period ending at 9 AM on January 3 at the Norton Water Plant ( * ).  

This yielded 6.5" of total snowfall, with a mean depth of 5" at 9 AM.

Norton Water Plant rests at the northern base of High Knob ( 1881 vertical feet lower than its peak ).

*According to snow cores taken at Clintwood 1 W, rain gages had significant undercatches during this event.

In Clintwood a rain gage catch of 0.10" was in contrast to 0.16" obtained by taking cores of actual snow depth ( i.e., gusty winds forced a 38% undercatch on the official 8" NWS rain gage ).  The lower elevation, more sheltered Clintwood 1 W site is less windy than Norton WP ( suggesting Norton WP had greater undercatch ). Gage undercatches were aided by low snow density which ran in the 20:1 to 30:1 range.

Greater snowfall in Norton and portions of the upper Powell Valley were due to the January 2 snowstreak.

I want to highlight this snowstreak since it 
created something RARELY ever seen
in a low density snowfall regime. 

Heavy snow, with 3" of accumulation,
in Fort Blackmore of Scott County, Va.,
with NW air flow across the High Knob Massif.

Air flowing from the NW drops approximately 3,000 vertical feet upon crossing the wide expanse of the High Knob Massif into the Clinch River Valley at Fort Blackmore.  This huge descent of air generates drying and warming.  With low density snowfall this typically dries the air so much that there is little to no sticking of snow even with deep accumulations on windward slopes of the massif.  More often than not, low density snow produces only flurries when NW-N winds blow into historic Fort Blackmore!

NASA Visible Image At 11:01 AM on January 4, 2012

Description of above image...

Same Image With Labels And Descriptions

Flip back and forth between the above images within the viewing section to get a feeling for features described, with the inverted V-shape of the Head of Powell Valley outlined amazingly well on this 1 KM image of relatively low resolution.

This snowstreak was extremely well supported by -35 to -40 degree below zero temperatures aloft, at around 17,000 feet, along a nearly unidirectional 850 to 700 mb flow field from Lakes Superior and Michigan ( always prime for S++ in the High Knob Massif ).

NAM Model 850 MB Initialization at 7 PM - January 2, 2012

NAM Model 700 MB Initialization at 7 PM - January 2, 2012

The heaviest snow with the snowstreak fell along State Route 619 and across portions of  U.S. Forest Service 238, 237, and 704 in the same sections that Roddy and Bill left with 4" of snow depth during afternoon hours of January 2.

It also hit hard, of course, along U.S. 23 and adjoining roadways from upper portions of Powell Valley into at least southwestern portions of the City of Norton.

Addison & Elizabeth Stallard, my friends and long-time weather observers in the Head of Powell Valley verified this heavy snow by reporting 5" to 6" of accumulation at their 1945 foot elevation ( * ).

*The snowstreak boosting their total snow depth to more than reported in Wise, as noted below, which missed this intense band of heavy snow.

Snow Still Falling In Wise at 7 AM - January 3, 2012
Photograph by Roddy Addington - © All Rights Reserved.

Snow depths on the morning of January 3 varied from around 4" in Wise to a general 5" to 10"+ across northern slopes, crests, and lofty basins of the High Knob Massif ( some 4" to 6" falling after Roddy left on January 2 ). 

Several inches fell during the snowstreak and several more inches fell on NW upslope flow overnight into January 3 amid a more widespread fall of light to moderate snow.

Locations missing out on the snowstreaks and NW usplope flow snow got much less, with instability driven snow showers and local squalls on January 2 providing their main accumulation.

JKL Doppler Reflectivity at 12:24 AM - January 3, 2012

Snowstreaks continued streaming across the High Knob Landform and over extreme southeast Kentucky until after midnight, finally giving way to a general NW upslope flow snowfall regime by 2 to 3 AM on January 3.

JKL Doppler Reflectivity at 2:42 AM - January 3, 2012

Due to upward tilting of the Doppler beam with increasing distance from the radar site it is harder to pick up general upslope flow snow across the High Knob Massif, with overshooting of snow clouds which develop lower toward the summit level of the massif ( i.e., upslope flow snow is more productive than radar indicated ).

The JKL Doppler is; however, by far the best located radar for detecting snow falling in this area where a large void used to be observed before it was placed near Jackson, Kentucky.


A Photographic Expose 
From Long Ridge of the Tennessee Valley Divide

Breathtaking Is
The Morning!

7:46 AM on January 2, 2012
Majestic Morning Sun Pillar Before The Snow
Photograph by Genevie Riner - © All Rights Reserved.

My friend Genevie Riner offers a time sequence of photographs that will beautifully recap what has been discussed above as these events unfolded in the highlands of southern Dickenson County.

Arctic Front Arrives 
On Long Ridge

2:53 PM on January 2, 2012
Photograph by Genevie Riner - © All Rights Reserved.

2:54 PM on January 2, 2012
Photograph by Genevie Riner - © All Rights Reserved.

The Orchard Road Vanishes 
Amid A Fury Of Snow!

2:57 PM on January 2, 2012
Photograph by Genevie Riner - © All Rights Reserved.

Snow Squalls Pass
( For The Moment )

3:36 PM on January 2, 2012
Photograph by Genevie Riner - © All Rights Reserved.

The highlands are snow covered in wake of the furious arctic front, with temporary holes of blue showing in the overcast.

Skies Darken As Another Squall Forms 
( In the Distance )

3:40 PM on January 2, 2012
Photograph by Genevie Riner - © All Rights Reserved.

3:41 PM on January 2, 2012
Photograph by Genevie Riner - © All Rights Reserved.

Wayne Riner Photograph Thoughts...
"This picture could be called: Quietness of the Cemetery After a Light Accumulation...A black cloud in the background brings more snow!"

3:42 PM on January 2, 2012
Photograph by Genevie Riner - © All Rights Reserved.


Instability In The Heavens
Revealed With Awesome Majesty

3:54 PM on January 2, 2012
Photograph by Genevie Riner - © All Rights Reserved.

The revelation of squalls to come was displayed by these incredible cloud structures developing amid the heavens above, where air was growing VERY COLD to make the atmosphere unstable.

3:55 PM on January 2, 2012
Photograph by Genevie Riner - © All Rights Reserved.


Night Falls Upon The Highlands 
And So Does New Snow!

12:04 PM on January 3, 2012
Photograph by Genevie Riner - © All Rights Reserved.

A total of 5.2" of snow were measured at Nora 4 SSE by Wayne & Genevie Riner during this event, with snow continuing to fall into afternoon hours of January 3.

12:12 PM on January 3, 2012
Photograph by Genevie Riner - © All Rights Reserved.

January 3 was a bitter day in the mountains with MAX temperatures only in the single digits and teens above 2000 feet [ ( 17 degrees on Long Ridge and 18 degrees in the City of Norton ( single digits above 3300 feet in the High Knob Massif ) ].

2:52 PM on January 3, 2012
Looking Toward Breaks Interstate Park from Long Ridge
Photograph by Genevie Riner - © All Rights Reserved.

Breaks Interstate Park is located at the downward sloping end of Pine Mountain whose rugged, cliff laden crestline is seen above dropping toward the northeast into magnificent Breaks Gorge of the Russell Fork River of the Ohio River Basin ( historically known as "Breaks of the Cumberlands" or "Breaks of the Sandy" ).

Thanks to Genevie for allowing us
to witness this documentary!



Coldest Day
Of The Season
( As of early January 2012 )

NASA Visible Image At 9:40 AM - January 3, 2012

Note many gravity waves coming off the Appalachians and stratocumulus forming in cold air streaming across the Atlantic Ocean ( which is warm relative to air above it ).

A beautiful array of orographic mountain waves were associated with the coldest day of the winter season to date, with raised gravity waves noted above from the High Knob Massif southeast to the TN-NC border ( where they merge with upslope clouds ).

A very interesting satellite image since the raised portion of these wave clouds correlate well with the higher topographical relief of the massif between the Duffield Valley of Scott County and eastern flanks of Clear Creek Basin in Wise County ( locally called Bowman Mountain ).

Reference the following to learn more about 
this higher topographical section:

High Knob Massif Structural Geology
The Duplex Portion of Higher Topographical Relief

The wild aspect of course being the downstream projection of this raised mass of mountain wave clouds into Tennessee!




Coldest Morning
Of Season Follows Coldest Day

January 4, 2012
Majestic Morning Sunrise Above Coeburn
Photograph by Roddy Addington - © All Rights Reserved.

Single digit morning lows were common above the fresh snowpack despite an abundance of mid-high altitude cloudiness that generated an awesome sunrise above the town of Coeburn on January 4.

Morning MINS of 0 to 10 degrees would have gotten even colder had skies remained clear over the fresh fall of snow.

Sunrise of January 4, 2012
Gorgeous Colors - Altocumulus & Mountain Wave Clouds
Photograph by Roddy Addington - © All Rights Reserved.

NW Upslope Flow Event
Summary of Snowfall Totals
( January 2-3, 2012 )

Elevation 1560 feet
Clintwood 1 W: 4.5"

Elevation 2650 feet
Nora 4 SSE: 5.2"

Elevation 2342 feet
Norton Water Plant: 6.5"

Elevation 3300 feet
High Chaparral of High Knob Massif: 7.0"

Elevation 4189 feet
*Eagle Knob of High Knob Massif: 10.0"

*The deepest snow in the southern Appalachians was within High Knob Lake Basin during morning hours of January 3.



Ready Or Not...Here We Come
Special Treat From Lee County

January 3, 2012
Sliver Leaf of Lee County
Baby Lamb Makes A New Friend
Photograph by Harold Jerrell - © All Rights Reserved.

My friend Harold Jerrell has been keeping busy lately with new born lambs, the first born on Christmas Eve was named Eve!

Amazingly, Eve's Mother was also
born on a previous Christmas Eve.

January 3, 2012
Sheltered From The Arctic Blast
Photograph by Harold Jerrell - © All Rights Reserved.

When January 2012 arrived so did 
a double set of twins!

One set arrived January 1 and the other came January 2.

Not a good time amid an arctic blast, but ready or not they came anyway!

January 3, 2012
Amid the Calcareous Heart of The High Knob Landform
Silver Leaf Community of Lee County, Virginia
Photograph by Harold Jerrell - © All Rights Reserved.

Harold reported 3" of snow depth in Silver Leaf as some heavy squalls made it across the mountain flanks into majestic, rolling karst valleys of central-western Lee County of the High Knob Landform.

January 3, 2012
Decorated With A Ball Of Fresh Snow
Photograph by Harold Jerrell - © All Rights Reserved.



Climate Statistics
For December 2011

AM of December 31, 2011
Lonesome Pine Airport in Wise
Turbulent Wave Clouds Above Wise Airport
Photograph by Roddy Addington - © All Rights Reserved.

( Lower Elevations of Russell Fork Basin )
Clintwood 1 W – Elevation 1560 feet
Average Daily MAX: 49.9 degrees
Average Daily MIN: 27.9 degrees
MEAN: 38.9 degrees
Highest Temperature: 66 degrees
Lowest Temperature: 16 degrees
Total Precipitation: 4.17”
Total Snowfall: 1.2”
2011 Precipitation: 60.98”

( Northern Base of High Knob Massif )
City of Norton – Elevation 2141 feet
Average Daily MAX: 47.1 degrees
Average Daily MIN: 25.8 degrees
MEAN: 36.4 degrees
Highest Temperature: 62 degrees
Lowest Temperature: 13 degrees
Total Precipitation: 5.63”
Total Snowfall: 4.5”
2011 Precipitation: 76.46”

( Along the Tennessee Valley Divide )
Nora 4 SSE – Elevation 2650 feet
Average Daily MAX: 46.0 degrees
Average Daily MIN: 31.4 degrees
MEAN: 38.7 degrees
Highest Temperature: 61 degrees
Lowest Temperature: 19 degrees
Total Precipitation: 4.39”
Total Snowfall: 6.2”
2011 Precipitation: 57.43”

( Northern Edge of The Cedars )
Jonesville 3.1 WSW - Elevation 1422 feet
Average Daily MAX: 52.6 degrees
Average Daily MIN: 29.6 degrees
MEAN: 41.1 degrees
Highest Temperature: 68 degrees
Lowest Temperature: 14 degrees
Total Precipitation: 4.77"
Total Snowfall: Trace
2011 Precipitation: 57.95"

In the High Knob high country temp means varied from 40 to 45 degrees by day at the higher elevations to low-mid 20s in colder basins at night ( upper 20s on some exposed ridges ).

A relatively mild December 
by highcountry standards.

Precipitation was abundant with 5.00" to 7.00" across the massif, heaviest from Bowman to Powell mountain's in the main crest zone.  This included a general 6" to 8" of snowfall above 3000 feet ( much below average ).

There were 12 days during the month with 1" or more of snow depth in High Knob Lake Basin ( 21 days for the season ).

My friend Gary Hampton, Superintendent of the Big Stone Gap Water Plant, and his fine staff, measured 6.62" of precipitation during December at Big Cherry Dam ( 15.29" during November-December ).

My friends Otis & Nancy Ward measured 5.40" of total  December precip in Robinson Knob of the High Knob Massif ( 15.78" November-December ).



Climate Statistics
For The Year 2011

Wise Reservoir - PM of January 4, 2012
Photograph by Roddy Addington - © All Rights Reserved.

( Lower Elevations of Russell Fork Basin )
Clintwood 1 W - Elevation 1560 feet
Average Daily MAX: 65.0 degrees
Average Daily MIN: 41.6 degrees
MEAN Temperature For 2011: 53.3 degrees
Total Precipitation: 60.98"

( Northern Base of High Knob Massif )
City of Norton - Elevation 2141 feet
Average Daily MAX: 62.7 degrees
Average Daily MIN: 39.7 degrees
MEAN Temperature For 2011: 51.2 degrees
Total Precipitation: 76.46"

( Along the Tennessee Valley Divide )
Nora 4 SSE - Elevation 2650 feet
Average Daily MAX: 61.5 degrees
Average Daily MIN: 44.6 degrees
MEAN Temperature For 2011: 53.0 degrees
Total Precipitation: 57.43"

In the High Knob high country 2011 temp means varied from middle-upper 50s by day at highest elevations to mid-upper 30s at night in colder basins ( around 40 degrees on exposed ridges ).

Mean temperatures for the year varying within the 46 to 52 degree range above 2700 feet ( as a general range estimate with changing exposure and elevation ).

Precipitation was abundant, to say the least, with 80.00" to 85.00" being typical in upper elevations.


Final Precipitation Totals
For 2011 From Across The Region

January 3, 2012 at 3 PM
University of Virginia's College In Wise
Photograph by Roddy Addington - © All Rights Reserved.

The precipitation gradient across Virginia was simply huge during 2011 with 45" to 50"+ spreads between wetter portions of the High Knob Massif and drier sections of the Old Dominion.

2011 Precipitation Totals

Buggs Island Dam: 34.55"

Wallops Island: 36.23"

Huddleston 4 SW: 36.64"

Altavista: 37.14"

Bluestone Lake ( WV ): 37.21"

Danville Cooperative: 37.28"

South Boston: 38.30"

Princeton ( West Virginia ): 38.37"

Danville Airport: 38.96"

Lewisburg 3 N ( West Virginia ): 38.97"

Lynchburg: 38.98"

Pulaski 2 E: 39.13"

Staffordsville 3 ENE: 39.77"

Emporia 1 WNW: 40.24"

Gathright Dam: 40.77"

Wytheville 1 S: 41.50"

Buena Vista: 41.53"

Covington Filter Plant: 41.79"

Martinsville Filter Plant: 41.86"

Beckley ( West Virginia ): 42.15"

Chatham: 42.27"

Brookneal: 42.73"

Kerrs Creek 6 WNW: 42.92"

Winchester: 42.94"

Lexington: 43.12"

Bluefield ( West Virginia ): 44.16"

Blacksburg NWSO: 44.44"

Lafayette 1 NE: 44.54"

Concord 4 SSE: 44.55"

Greenbay 3 NE: 44.72"

Painter 2 W: 44.97"

Roanoke: 45.03"

Alberta 5 N: 45.36"

Radford 3 N: 45.44"

Staunton WTP: 45.46"

Bland: 45.75"

Saltville 1 N: 46.13"

Washington Dulles Airport: 46.20"

Washington National Airport: 46.89"

Richmond: 47.54"

Buckingham: 47.62"

Tri-Cities ( Tennessee ): 47.68"

Suffolk Lake Kilby: 48.27"

Charlottesville: 48.31"

Trout Dale 3 SSE: 50.27"

Richlands: 50.68"

Burkes Garden: 50.70"

Norfolk: 51.10"

Hot Springs: 52.01"

Glasgow 1 SE: 52.54"

Grundy: 52.71"

Charlottesville 2 W: 52.99"

Galax WTP: 53.08"

Lebanon: 56.25"

Nora 4 SSE: 57.43"

Woolwine: 57.57"

Jonesville 3.1 WSW: 57.95"

Jackson ( Kentucky ): 60.01"

Clintwood 1 W: 60.98"

Coeburn Filtration Plant: 67.81"

Wise 3 E: 67.81"

( Little Stone Mountain of High Knob Massif )
Appalachia Lake Water Plant: 67.89"

Meadows of Dan 5 SW: 68.89"

( South Fork Gorge of High Knob Massif )
Big Stone Gap Water Plant: 70.94"

( Northern base of High Knob Massif )
Norton Water Plant: 76.46"

( High Knob Massif )
*Big Cherry Dam: 80.25" ( M )

( High Knob Massif )
Robinson Knob: 81.14" ( M )

( M ) - Denotes missing moisture in deep falls of snow and evaporative losses between hand-measurements ( significant at Big Cherry Dam throughout the year but mainly during the cold season in Robinson Knob ).

*The 80.25" at Big Cherry Dam produced a 3-year precipitation average of 75.73" ( M ):

Big Cherry Dam 
Yearly Precipitation

2009
81.34" ( M )

2010
65.60" ( M )

2011
80.25" ( M )

MEAN: 75.73" ( M )

The November 2008 to December 2011 total of 240.04" produced a monthly mean of 6.32" during this 38 month period
( the highest ever observed in Virginia ).

It is conservatively estimated that an average of 0.25" was lost per month during this 38-month period due to evaporation and deep falls of snow.

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