Friday, March 29, 2013

March 2013 - Colder & Snowier Than Average


March 26, 2013
Along The High Knob Massif Crest Zone
Looking Like Mid-Winter In Spring 2013
Photograph by Bill Harris - © All Rights Reserved.


As the first month of meteorological spring approached its end yet another blast from the 
Ole Man of Winter transformed the mountain landscape into a wonderland of snow and rime.

March 26, 2013
Along The High Knob Massif Crest Zone
Entrance To High Knob Lake Recreation Area
Photograph by Bill Harris - © All Rights Reserved.

This was a prolonged event with continuous snow falling from March 24-27 in upper elevations of the High Knob Massif, and during March 25-27 at mid and lower elevations along the upslope side of the southern Appalachians.

March 25, 2013
Southern Wise County
Beginning Of A Prolonged Upslope Snow Event
Photograph by Roddy Addington - © All Rights Reserved.

Rod Addington Photography

Darlene Fields said if spring was never coming at least she had a nice "Snowball Bush" in her yard!

March 26, 2013
High Chaparral of High Knob Massif
Snowball Bush Of Ole Man Winter's Design
Photograph by Darlene Fields - © All Rights Reserved.



History Of The Miller B
Winter Storm of March 24-27

Climatology dictates that most of the snow with winter cyclones of the Miller B type typically falls with upslope flow amid the backside circulation of these systems along the western Appalachians.

March 24, 2013 at 8:00 AM ( 1200 UTC )
European Model 850 MB & Surface Initialization

That certainly was the case with this system, as the Warm Air Advection ( WAA ) snow of the frontside fell within the Cold Air Damming ( CAD ) zone generated by evaporative cooling and transport of colder air into eastern slopes of the Appalachians.

Snow totals with this Miller B Storm's WAA phase were much less than those associated with the Miller B storm of March 5-7 when 18-24 inches accumulated at highest elevations of the northern
Blue Ridge in Virginia.  Upslope snow along the western slopes, by contrast, was much greater during March 25-27 vs. March 5-7.

March 24, 2013 at 8:00 PM ( 0000 UTC )
European Model 850 MB & Surface Initialization

Miller B cyclones are typically complex, especially as regards the vertical temperature profile, since an initial low center tends to propagate along the western slopes of the Appalachians as a secondary low forms to the east, lee of the mountains.  The secondary low then becomes the primary storm center as the western low weakens.

Miller A Verses Miller B Winter Storms
Favorable Patterns For Winter Winter
( Courtesy of State Climate Office of North Carolina )

Snow, sleet, freezing rain or a mixture occurs along 
the eastern Appalachians ( with snow favored farther northeast vs. southeast along the mountain chain ) as a deeper layer of warm air aloft supports mostly rain along the western Appalachians during this WAA phase.

The Cold Air Advection ( CAA ) phase, as highlighted in detail below, being typically the most productive snow producer along the western front range of the Appalachians with Miller B storms.

[ Miller A Winter Storms, especially northward tracking variants, like exemplified by the crippling snow falls of January 1998 and December 2009, are completely different animals and can be potent snow producers ].

March 25, 2013 at 8:00 AM ( 1200 UTC )
European Model 850 MB & Surface Initialization

Rain changed to wet snow at highest elevations in the High Knob Massif, above 3300 feet, during evening hours of March 24 on SW-WSW 
low-level air flow trajectories.  

A general 1-2" accumulated on Eagle Knob ( 4189 feet elevation ) before snow even started to stick much at the 3300 foot level in High Chaparral ( 4.1 air miles east of the High Knob peak ).

Snowfall increased significantly 
into morning hours of March 25.

A backward air flow trajectory calculation using the NOAA HYSPLIT Model also revealed that the air had a notable Great Lake connection.


It was no surprise to find abundant moisture on the 1200 UTC NAM Model Initialized Sounding above Wise ( with 12-18 hours of steady upward rising motion aiding condensation and snowfall ).

March 25, 2013 at 8:00 AM ( 1200 UTC )
NAM Model Initialized Sounding Above Wise

This marked a period of SW-WSW upslope flow that produced a general 1" to 5" of snow depth in the typically favored SW Upslope Flow snowfall zone by mid-day on March 25 ( * ). 

*The SW Upslope Flow zone extends from the High Knob Massif and Tennessee Valley Divide southwest through Norton-Wise 
into the Powell River Basin of Lee County.

( Climatology of SW Upslope Flow Snow )
SW Upslope Flow Event of February 2013

( 3.5" of Snowfall )
March 25, 2013 at 11:02 AM
High Chaparral of High Knob Massif
Photograph by Darlene Fields - © All Rights Reserved.

During this same time only a dusting of snow accumulated in much of the Russell Fork and Levisa Fork basins on downslope flow into communities such as Pound, Clintwood, 
Haysi, and Grundy.

March 25, 2013 ( Monday )
Middle Elevations of SW Upslope Flow Zone
Morning Snow & Slick Roads In Wise County
Photograph by Roddy Addington - © All Rights Reserved.

Residents in northern Wise County wondered why school was closed Monday to illustrate the large contrast in conditions between locations such as Pound & Wise ( elevation + upslope/downslope = large contrast ).

March 25, 2013 In Wise County
Wise Plateau of Tennessee Valley Divide
AM Conditions In WSW-SW Upslope Flow Zone
Photograph by Roddy Addington - © All Rights Reserved.

A large contrast was also observed in Dickenson County, between Sandy Ridge and Clintwood, but county schools were out for "spring" break!

March 25, 2013 at 9:51 AM
Long Ridge of Tennessee Valley Divide
Maple Buds Of Spring Contrast With Snow
Photograph by Wayne Riner - © All Rights Reserved.

Wayne Riner Photograph Thoughts...
"The maple tree has red buds in the process of blooming.  However, Monday morning's snow is 
in contrast to spring on the calendar."

March 25, 2013 at 8:00 AM ( 1200 UTC )
European Model 500 MB & Surface Initialization

Another factor aiding snowfall on the synoptic scale was cold air aloft associated with a closed 500 MB low passing across the Appalachians, with low-level wind trajectories backing WNW-NW into the afternoon and evening hours of March 25.

This contributed to snow squalls with bursts of heavy snow during the afternoon.  Sticking and melting occurred at lower elevations, with significant accumulations observed above 2500 to 3000 feet ( especially in the High Knob Massif - Black Mountain corridor ).

( 6.5" of total snowfall )
March 25, 2013 at 5:10 PM
New Snow In High Chaparral of High Knob Massif
Photograph by Darlene Fields - © All Rights Reserved.

Darlene illustrates the most accurate way to measure snowfall, with snow on the left side of her picnic table above having been swept clean from the morning accumulation.  The snow on the left seen above having accumulated in the 6 hours between 11:02 AM and 5:10 PM 
( 3.0" of new to make 6.5" in total ).

This method of measuring follows National Weather Service Cooperative Guidelines and The Snow Booklet 
as outlined by The Colorado State Climate Center.

Colorado State University - The Snow Booklet

Elevation 3300 feet
High Chaparral of High Knob Massif
New Snow Swept Clean Again At 5:11 PM
Photograph by Darlene Fields - © All Rights Reserved.

Ideally, snow should be measured and swept every 6 hours that it accumulates.  You do not want to sweep off the snow more often than every 6 hours or it could erroneously inflate the storm total fall.  On the other hand, if snow sticks and then melts each sticking should be measured or estimated and added to make the total fall.
A total of 4 intervals of 6 hours with accumulation = the 24-hour snowfall total.  If snow melts continuously and never sticks the total is counted as a trace.

Snow is measured and swept in order to minimize factors such as settlement, compression, and other processes like sublimation and melting that alter the snow depth over time.  Wind can also be a major factor hard to deal with, requiring long-time ( veteran ) snow measuring skills in order to determine its impact and obtain a reasonably accurate estimate for the total fall.

Prolonged snow events like this present an added challenge, with higher spring sun angles and the tendency for melting by day and sticking at night having to be understood and recognized in order 
to capture the amount of snow that really falls.

Variations observed at UVA in Wise are illustrative.

March 25, 2013 at 10:27 AM
University of Virginia's College In Wise

Note the considerable amount of melting which occurred 
between 10:27 AM ( above ) and 3:26 PM ( below ).

March 25, 2013 at 3:26 PM
University of Virginia's College In Wise

New sticking occurred in late afternoon ( below ).

March 25, 2013 at 6:08 PM
University of Virginia's College In Wise

By 5:10 PM on March 25, when Darlene Fields had measured 6.5" of total snowfall in High Chaparral, there had been less than 0.5" of accumulation at my station in Clintwood.

A general 8" to 9" of snow had accumulated along the main crest zone of the High Knob Massif by 5:00 PM on March 25, with heavy snow accumulations as well along Big Black Mountain where KDOT reported 6" of depth on State Route 160 by 1:32 PM.

March 25, 2013 at 8:00 PM ( 0000 UTC )
European Model 850 MB & Surface Initialization

Continuous snow fell on WNW-NNW winds from the evening of March 25 through March 26, with significant additional snow adding to depths at all elevations along the upslope side of the mountains.

March 25, 2013 at 8:00 PM ( 0000 UTC )
NAM Model Initialized Sounding Above Wise

March 26, 2013 at 8:00 AM ( 1200 UTC )
NAM Model Initialized Sounding Above Wise

The major differences in the above soundings being a shift to complete saturation below 800 MB and a backing of the wind field to NW-NNW by 8:00 AM on March 26 above the Wise gridpoint.

March 26, 2013 at 8:00 AM ( 1200 UTC )
European Model 850 MB & Surface Initialization

This kept a layer of pilatus clouds capping the High Knob Massif which acted as feeder clouds through which falling snowflakes would be rimed to aid enhancement of snowfall and depth in the highest elevations ( an orographic effect ).

A calculation of backward air flow trajectories at 
6 hour intervals into the morning of March 26 revealed a significant Great Lake connection to supply the needed low-level moisture that was being orographically lifted to generate the riming cloud layer and continuous snowfall across the High Knob Massif.

Backward Air Flow Trajectories At 1000 Meters
( Changes In 6-hour Increments From Left to Right )

Backward Air Flow Trajectories At 1450 Meters
( Changes In 6-hour Increments From Left to Right )

March 26, 2013
Rime Does More Than Add Water Content
Riming In High Knob Massif Crest Zone
Photograph by Bill Harris - © All Rights Reserved.

So rime does more than just add water content to snowpacks, it also acts to aid snowfall itself during periods when snow is falling through the super-cooled clouds of vapor that generate all the riming of trees, bushes, and above ground objects.

This is the seeder-feeder process of the winter, or cold season, atmosphere which enhances precipitation, in this case snowfall, via riming of snow flakes to add both to their fall efficiency and their volume ( as the summer seeder-feeder process works to enhance the amount of rainfall reaching the surface its winter counterpart works to enhance the amount of snow that falls and accumulates on the ground amid the high country where riming is most active and vigorous ).

March 26, 2013 at 8:00 PM ( 0000 UTC )
European Model 850 MB & Surface Initialization

Snow accumulated into morning 
hours of March 27.

Morning of March 27, 2013
High Chaparral of High Knob Massif
Ready For More Snow - Depth Increases
Photograph by Darlene Fields - © All Rights Reserved.



Storm Snowfall Statistics
For March 24-27 & Winter 2012-13

( Northern Base of High Knob Massif )
City of Norton Water Plant 
Observer: Superintendent Andrew Greear
Elevation 2342 feet

Storm Total Snowfall: 10.0” 
( 0.69” of snow water equivalent / 5.83” March )

Max Mean Snow Depth: 8”

March snowfall: 20.8”

2012-13 Season Snowfall 
Total: 65.3” ( 5.4 feet )


Snow Depth On Wise Mountain
Courtesy of Judy Horne & WCYB-TV Photo Archive


( Head of Burns Creek & Little Stony Creek )
High Chaparral of High Knob Massif
Observer: Darlene & Joe Fields
Elevation 3300 feet

Storm Total Snowfall: 13.5”

Max Mean Snow Depth: 11”

March snowfall: 27.0”

2012-13 Season Snowfall 
Total: 90.5” ( 7.5 feet )


High Chaparral of High Knob Massif
Closing In On A Foot of Ground Snow Depth
Photograph by Darlene Fields - © All Rights Reserved.


( South Fork of Powell River Basin )
Little Mountain of High Knob Massif
Observer: James & Carol Bolling
Elevation 3420 feet

Storm Total Snowfall: 14.5”
Large Snow Drifts Along Route 237


( Eagle Knob Communications Area )
Eagle Knob of High Knob Massif
Observer: Steve Blankenbecler & Wayne Browning
Elevation 4189 feet

Storm Total Snowfall: 18.0”
Variable ground depths ( < 6" to >24" )

March snowfall: 36.5”

2012-13 Season Snowfall 
Total: 130.0” ( 10.8 feet )

91 Days ( 13 weeks ) of 1" or More 
Snow Depth In High Knob Lake Basin

March 27, 2013
Eagle Knob of High Knob Massif
Image by Steve Blankenbecler - © All Rights Reserved.

Mid-upper elevations ( > 2000 feet ) of central-southern 
Wise County and extreme northern Scott County had the most snow during this March 24-27 Miller B winter storm episode, with a general 8"-18" of total snowfall.

Ground depths varied from less than 6" to 2 feet or more in drifts, but generally were less than the total fall of snow due to daily melting, settlement, and compaction.


( Along the Tennessee Valley Divide )
Nora 4 SSE on Long Ridge
Observer: Wayne & Genevie Riner
Elevation 2650 feet 

Storm Total Snowfall: 6.1”
( 0.39” of snow water equivalent / 4.39” March )

March snowfall: 15.1”

2012-13 Season Snowfall 
Total: 56.8” ( 4.7 feet )


March 25, 2013 ( Monday )
Cemetery In The Snow On Long Ridge
Photograph by Wayne Riner - © All Rights Reserved.

Wayne Riner Photograph Thoughts...
"The calendar tells of spring and daffodils.  Monday's snow gives us a reality check."


( Lower Elevations of Russell Fork Basin )
Clintwood 1 W 
Observer: Wayne Browning
Elevation 1560 feet

Storm Total Snowfall: 4.3”
( 0.24" of snow water equivalent / 4.31" March )

Max Mean Snow Depth: 2"
( Local snow drifts to 6-7" )

March snowfall: 13.1”

2012-13 Season Snowfall 
Total: 40.5 ( 3.4 feet )


Lower elevations of northern Wise County and much 
of Dickenson & Buchanan counties ( < 2000 feet ) had much less snow with only 1" to 3" on the ground at any given time ( generally 3" to 5" of total snowfall ). 



Climate Statistics
For March 2013

Carolina Wren ( Thryothorus ludovicianus )

One of my favorite, feisty little birds 
is ready for SPRING to really arrive!

( Lower Elevations of Russell Fork Basin )
Clintwood 1 W - Elevation 1560 feet
Average Daily MAX: 46.4 degrees
Average Daily MIN: 25.7 degrees
MEAN: 36.0 degrees
Highest Temperature: 75 degrees
Lowest Temperature: 12 degrees
Total Precipitation: 4.71"
Total Snowfall: 13.1"
2013 Precipitation: 13.60"

( Northern Base of High Knob Massif )
City of Norton - Elevation 2141 feet
Average Daily MAX: 42.6 degrees
Average Daily MIN: 23.4 degrees
MEAN: 33.0 degrees
Highest Temperature: 67 degrees
Lowest Temperature: 10 degrees
Total Precipitation: 6.34"
Total Snowfall: 20.8"
2013 Precipitation: 18.78"

( Along the Tennessee Valley Divide )
Nora 4 SSE - Elevation 2650 feet
Average Daily MAX: 41.3 degrees
Average Daily MIN: 25.2 degrees
MEAN: 33.2 degrees
Highest Temperature: 66 degrees
Lowest Temperature: 14 degrees
Total Precipitation: 4.62"
Total Snowfall: 15.1"
2013 Precipitation: 14.36"

In the High Knob Massif mean days were in the 30s to around 40 degrees above 2700 feet and nights in the upper 10s to lower 20s.

This generated a mean temperature for the month that was colder than December 2012, which was anomalously mild, and not much above January.   

March was wet with more than 7.00" of water equivalent precipitation in upper elevations of the High Knob Massif, as well as across portions of western Lee County, to include several feet 
of snow at higher elevations in the massif.

Superintendent Gary Hampton & staff measured 7.65" of water equivalent precip at Big Cherry Dam during March, despite some missing moisture in significant falls of snow ( suggesting up to 8.00" or more fell in Big Cherry Basin during the month ).

A total of 21.76" were hand-measured at Big Cherry Dam 
during January-March for an average of 7.25" per month.

It must be noted, however, that both this average and the January-March total was higher given more than 1.00" of moisture loss from the gauge in deep falls of snow.

The 4"-diameter NWS rain gauge was read by hand
13 times during January-March at Big Cherry Dam
( an average of 1 time per week ).


Precipitation Statistics
For December 2012 - March 2013

March 2013
Starting To Show Some Color
American Goldfinch ( Carduelis tristis )

Mountains & Western Piedmont
of Southwestern Virginia

Grundy
Elevation 1170 feet
March: 3.59"
January-March: 10.76"
December-March: 13.50"

Wytheville 1 S
Elevation 2450 feet
March: 2.92"
January-March: 12.42"
December-March: 15.07"
( 2012-13 Winter Snowfall: 19.1" )

Richlands
Elevation 1910 feet
March: 3.92"
January-March: 12.50"
December-March: 15.94"
( 2012-13 Winter Snowfall: 27.1" )

Copper Hill
Elevation 2690 feet
March: 3.00"
January-March: 13.84"
December-March: 16.52"
( 2012-13 Winter Snowfall: 30.3" )

Lebanon
Elevation 1912 feet
March: 4.01"
January-March: 14.06"
December-March: 17.13"

Clintwood 1 W
Elevation 1560 feet
March: 4.71"
January-March: 13.60"
December-March: 17.50"
( 2012-13 Winter Snowfall: 40.5" )

Saltville 1 N
Elevation 1733 feet
March: 4.05"
January-March: 14.26"
December-March: 17.58"

Galax WTP
Elevation 2360 feet
March: 3.02"
January-March: 15.48"
December-March: 18.14"

Trout Dale 3 SSE
Elevation 2820 feet
March: 4.20"
January-March: 15.38"
December-March: 18.41"
( 2012-13 Winter Snowfall: 42.5" )

Nora 4 SSE
Elevation 2650 feet
March: 4.62"
January-March: 14.36"
December-March: 18.45"
( 2012-13 Winter Snowfall: 56.8" )

Burkes Garden
Elevation 3068 feet
March: 4.11"
January-March: 14.77"
December-March: 18.68"
( 2012-13 Winter Snowfall: 54.8" )

Martinsville FP
Elevation 760 feet
March: 2.93"
January-March: 15.67"
December-March: 19.32"
( 2012-13 Winter Snowfall: 3.0" )

Stuart
Elevation 1352 feet
March: 3.45"
January-March: 16.74"
December-March: 20.58"
( 2012-13 Winter Snowfall: 0.8" )

Woolwine
Elevation 1500 feet
March: 4.29"
January-March: 17.01"
December-March: 20.63"
( 2012-13 Winter Snowfall: 4.4" )

Meadows of Dan 5 SW
Elevation 2225 feet
March: 3.95"
January-March: 18.31"
December-March: 21.86"
( 2012-13 Winter Snowfall: 1.8" )

( NW Flank of High Knob Massif )
Appalachia Lake WP
Elevation 2350 feet
March: 5.93"
January-March: 17.84"
December-March: 23.06"

( Northern Base of High Knob Massif )
City of Norton WP
Elevation 2342 feet
March: 6.34"
January-March: 18.78"
December-March: 25.04"
( 2012-13 Winter Snowfall: 65.3" )

( South Fork Gorge of High Knob Massif )
Big Stone Gap WP
Elevation 1965 feet
March: 6.77"
January-March: 19.75"
December-March: 25.74"

Robinson Knob of High Knob Massif
Elevation 3240 feet
March: 7.01"
January-March: 20.51" ( M )
December-March: 27.30" ( M )
( 2012-13 Winter Snowfall: 90-100" )

Big Cherry Dam of High Knob Massif
Elevation 3120 feet
March: 7.65"
January-March: 21.76" ( M )
*December-March: 28.76" ( M )

( M ) - Indicates missing moisture in deeper falls of winter snow.

*While the raw rain gauge catch equals 0.93" per month more than the City of Norton, on average, the true difference during this 4-month interval, given more than 1.00" of moisture loss in deep falls of snow, was actually 1.25" to 1.50" more per month
at Big Cherry Dam ( as suggested by reported snowfall ).

A listing of these precipitation statistics for meteorological winter ( December-February ) and March reveals large variations in amounts across southwestern Virginia, with a listing from least to greatest amounts for the 4 month period.

Amounts of 25.00" to 30.00"+ during the 4 month period amid the High Knob Massif area have been much greater than those observed in surrounding locations of the Ohio ( Russell Fork & Levisa Fork ) and Upper Tennessee river basins.

Wetter portions of the High Knob Massif averaged from near 3.00" to 4.00" more per month than places under downslope flow on mean SW-WSW winds during December 2012 to March 2013.

December 1, 2012 to March 31, 2013
Mean 925 MB Air Flow Trajectories

Places immediately downslope of the High Knob Landform - Tennessee Valley Divide corridor included Pound, Clintwood, Grundy, Lebanon, and Richlands.

This also included higher terrain sites like Nora 4 SSE which measured 10.31" less than Big Cherry Dam despite being only
470 feet lower in elevation ( nearly 1600 feet lower than the massif ).  The true difference, of course, during the December-March period was closer to 11.50" to 12.00" less at Nora 4 SSE.

It may seem redundant to keep hammering this point of moisture losses at Big Cherry Dam; however, it is very important given rain gauge losses I have observed in the massif over the years and the fact that this is proving to be the wettest area in Virginia even with rain gauge losses at Big Cherry Dam and Robinson Knob.

At Big Cherry Dam the 18 hand measurements during December-March verses a possible 121 measurements 
( daily ) made a difference, as did over flow of the gauge by deep falls of snow too great for it to contain ( not to mention effects of wind which are being neglected as they basically are at all other observation sites ).

It is interesting to also note that wettest locations in the southern Blue Ridge & western Piedmont had little snowfall compared to observation sites along the western slopes of the mountains. 

This is also very important since places having much less snowfall tend to have much less rain gauge undercatch verses those sites having large amounts of snowfall.

These large variations also extended from the New River and Greenbrier River drainages across the Virginia & West Virginia border counties.


New River & Greenbrier Region
of Virginia - West Virginia

Alderson
Elevation 1540 feet
March: 2.32"
January-March: 7.42"
December-March: 10.21"
( 2012-13 Winter Snowfall: 15.8" )

Covington Filter Plant
Elevation 1230 feet
March: 2.14"
January-March: 7.77"
December-March: 10.23"
( 2012-13 Winter Snowfall: 11.1" )

Lewisburg 3 N
Elevation 2300 feet
March: 2.48"
January-March: 8.08"
December-March: 10.85"
( 2012-13 Winter Snowfall: 29.1" )

Gathright Dam
Elevation 1770 feet
March: 2.65"
January-March: 8.36"
December-March: 10.89"

Bluestone Lake
Elevation 1390 feet
March: 2.16"
January-March: 8.21"
December-March: 11.49"

White Sulphur Springs
Elevation 1920 feet
March: 2.59"
January-March: 8.54"
December-March: 11.72"
( 2012-13 Winter Snowfall: 21.1" )

Millgap 2 NNW
Elevation 2520 feet
March: 3.86"
January-March: 9.52"
December-March: 12.34"
( 2012-13 Winter Snowfall: 41.6" )

Buckeye
Elevation 2150 feet
March: 2.73"
January-March: 9.21"
December-March: 12.78"

Frost 3 NE
Elevation 2921 feet
March: 3.70"
January-March: 10.03"
December-March: 13.43"
( 2012-13 Winter Snowfall: 64.3" )

Bartow 1 S
Elevation 3025 feet
March: 3.76"
January-March: 10.25"
December-March: 13.48"
( 2012-13 Winter Snowfall: 86.1" )

Pulaski 2 E
Elevation 1850 feet
March: 2.61"
January-March: 11.37"
December-March: 13.73"
( 2012-13 Winter Snowfall: 15.2" )

Bluefield
Elevation 2857 feet
March: 3.42"
January-March: 11.09"
December-March: 14.26"
( 2012-13 Winter Snowfall: 55.1" )

Blacksburg
Elevation 2080 feet
March: 3.32"
January-March: 12.42"
December-March: 14.83"
( 2012-13 Winter Snowfall: 22.5" )

Hacker Valley
Elevation 1590 feet
March: 4.82"
January-March: 12.86"
December-March: 19.11"
( 2012-13 Winter Snowfall: 87.5" )

Snowshoe Mountain
Elevation 4850 feet
March: 6.10"
January-March: 16.30"
December-March: 21.58"
( 2012-13 Winter Snowfall: 187.1" )

Davis 3 SE
( Canaan Mountain )
Elevation 3815 feet
March: 5.01"
January-March: 15.56"
December-March: 23.27"
( 2012-13 Winter Snowfall: 221.8" )

Total precipitation throughout this region has generally been much less than across the southern Appalachians, from the High Knob Massif south, but total snowfall has been much greater along the highest windward slopes that face incoming 
Great Lake moisture in central-northern 
portions of West Virginia.

This is part of a general SW-NE gradient of precipitation across the southern-central Appalachians, with greatest total amounts in the southwest where annual average snowfall tends to be least
( e.g., southwestern North Carolina ).

Annual snowfall and depths tend to increase into New England with 78" of snow depth, for example, at 3900 feet elevation of
"The Stake" ( famous snow depth marker ) on Mount Mansfield in Vermont during March 31, 2013 ( * ).

*This SW to NE increase in mean annual snowfall along the Appalachians is not linear or consistent, but instead is broken into concentrated centers of greatest snowfall amounts such as the highest Smokies & Roan Mountain in Tennessee, Mount Mitchell in North Carolina, the High Knob Massif & Mount Rogers in Virginia, and the Kumbrabow State Forest to Canaan Mountain 
corridor of West Virginia.

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