Monday, July 4, 2011

Summer 2011 Opens WET In The HKL


Cumberland Gap National Historical Park
Wetness & Mountain Laurel ( Kalmia latifolia )
Photograph by Harold Jerrell - © All Rights Reserved.



June 2011 started dry but was destined to turn wet with rain gage totals as great as 11.82" being reported in Cumberland Gap National Historical Park ( NHP ), continuing the soggy trend established during meteorological spring.


Climate Statistics
For June 2011

( Lower Elevations of Russell Fork Basin )
Clintwood 1 W - Elevation 1560 feet
Average Daily MAX: 81.5 degrees
Average Daily MIN: 57.2 degrees
MEAN: 69.4 degrees
Highest Temperature: 89 degrees
Lowest Temperature: 48 degrees
June Rainfall: 6.25"
2011 Precipitation: 30.30"

( Northern Base of High Knob Massif )
City of Norton - Elevation 2141 feet
Average Daily MAX: 80.4 degrees
Average Daily MIN: 55.1 degrees
MEAN: 67.8 degrees
Highest Temperature: 87 degrees
Lowest Temperature: 45 degrees
June Rainfall: 6.40"
2011 Precipitation: 34.52"

( Along the Tennessee Valley Divide )
Nora 4 SSE - Elevation 2650 feet
Average Daily MAX: 78.2 degrees
Average Daily MIN: 61.3 degrees
MEAN: 69.8 degrees
Highest Temperature: 87 degrees
Lowest Temperature: 51 degrees
June Rainfall: 3.88"
2011 Precipitation: 28.27"

( Northern Edge of The Cedars )
Jonesville 3.1 WSW - Elevation 1422 feet
Average Daily MAX: 85.7 degrees
Average Daily MIN: 59.5 degrees
MEAN: 72.6 degrees
Highest Temperature: 92 degrees
Lowest Temperature: 48 degrees
June Rainfall: 3.88"
2011 Precipitation: 27.52"

In the High Knob Massif June temp means varied from 70-75 degrees in the higher elevations by day to 50-55 degrees at night amid cooler valleys of the high country.

June rainfall was above average with a general 5.00" to 10.00"+ during the month in the massif area ( including the towns of Appalachia, Big Stone Gap, Coeburn, Duffield, Wise, and the City of Norton ).

The greatest gauge totals in the entire High Knob Landform occurring at its southwestern end across portions of Cumberland Gap National Historical Park ( NHP ), as highlighted above, where significant flash flooding ravaged Middlesboro and adjacent communities during the morning hours of June 20 ( highlighted later amid the RING of FIRE section ).


Rewriting The Climatology
Of Virginia

Early October 2006
Looking Across Northwest Side Of Big Cherry Basin
Photograph by Dan Weemhoff - © All Rights Reserved.

This page archived by WebCite at:

While missing numerous heavy rains during the May to early July period of 2011, which developed adjacent to the Big Cherry Dam measuring point, longer term records from this location are helping to rewrite the precipitation climatology of Virginia.

Big Cherry Dam of High Knob Massif
Monthly Precipitation Totals
Elevation: 3120 feet

2008
November:  4.36"
December: 8.49"

2009
January: 9.23"
February: 4.36"
March: 5.51"
April: 5.40"
May: 7.07"
June: 5.44"
July: 8.42"
August: 7.08"
September: 9.09"
October: 4.36"
November: 3.88"
*December: 11.50"

2010
*January: 6.25"
*February: 4.25"
*March: 4.50"
April: 3.78"
May: 6.99"
June: 9.53"
July: 4.27"
August: 8.91"
September: 2.88"
October: 2.84"
November: 4.05"
*December: 7.35"

2011
January: 4.51"
February: 4.53"
March: 9.85"
April: 10.08"
May: 5.38"
June: 6.16"

2011 Total: 40.51" ( M )

Orographic Forcing Season Total
November 2010-April 2011: 40.37" ( M )
( 6.06" per month average )

12-Month Total: 70.81" ( M )

24-Month Total: 150.44" ( M )

2-Year Mean Precipitation: 75.22" ( M )

32-Month Total: 200.30" ( M )

32-Month Mean Monthly Precip: 6.26"

Mean Per 12-Month Periods: 75.12" ( M )

( * ) - Indicates that total was estimated or partly estimated due to severe winter conditions.

( M ) - Denotes that total precipitation was greater than rain gage total due to evaporation between hand-measurements observed at the Dam ( the mean evaporative loss is estimated to have been 3.00" to 3.50" per year as partly based upon observed losses at Clintwood 1 W ) and deep falls of snow greater than the rain gage could physically hold.

[ All measurements courtesy of Superintendent Gary Hampton & Staff at the Big Stone Gap Water Plant in South Fork Gorge ].

This 6.26" monthly mean during the previous 32-months translates to more than 75.00" of total precipitation for nearly 3 consecutive years.  

This is impressive for numerous reasons:

1 ).  It has never before been duplicated by a NWS-style rain gage outside of the High Knob Massif in Virginia ( not known from any properly placed rain gage ).

2 ).  It is known to be less than what actually fell at the Big Cherry Dam measuring point by up to 3.00"+ per year due to evaporation losses and loss in deep falls of snow.

3 ).  Comparison with City of Norton records and measurements in the High Knob Massif from both automated and NWS gages suggest that this 75"+ average per 3-year intervals has occurred several times in recent decades at Big Cherry Dam:

1989-1991
1994-1996
2002-2004

A NWS rain gauge has only been in place at Big Cherry Dam since autumn of 2007.  However, based upon City of Norton records and other NWS gage & automated locations across the area these above 3 year intervals would have been as wet or wetter than this most recent 32-month period in which Big Cherry Dam has averaged 10.88"+ more per year than the City of Norton ( * ).

*The City of Norton Water Plant was the wettest location in Virginia during a 1983-2003 data scan which compared all other locations in the Old Dominion with available data to it.

4 ).  From a natural sciences perspective the above is illustrating that Virginia has an area which over the longer term is as wet or wetter than the wettest locations in the eastern West Virginia highlands.

An area that also contains, not only by chance, the rarity & richness epi-center for limited range species in the continental United States ( * ).

*Precious Heritage: The Status of Biodiversity in the United States.  Oxford Press © 2000.

This wetness driving many aspects of the natural environment, not the least of which is exceptional karstification with breachment of its geological Powell Valley Anticline.

Reference following sections for more details:





5 ).  Wetness during this past 32-month period has been contributed to by heavy winter snowfall totals, which typically are a significant aspect of the climate in this portion of Virginia.


Recent Winter Snowfall Totals
By Season In The High Knob Massif

High Chaparral - Elevation 3300 feet
Observers: Joe & Darlene Fields

2008-09: 80.5"
2009-10: 124.0"
2010-11: 107.7"

3-Season MEAN: 104.1"

The Snowfall MEAN in High Chaparral for the 18-winter seasons from 1993-94 to 2010-11 was 76.1" ( this is the highest annual mean ever known to be observed in Virginia 
at a permanent residence ).

A Very Special Thanks To: 
Joe & Darlene Fields and family.



*Eagle Knob - Elevation 4189 feet
Observers: Steve Blankenbecler & Others

2008-09: 107.0"
2009-10: 166.0"
2010-11: 141.5"

3-Season MEAN: 138.2"

*Approximate seasonal totals.

The Snowfall MEAN on Eagle Knob for the 19-winter seasons from 1992-93 to 2010-11 was 108.4" ( this is the highest annual mean ever known to be observed in Virginia ).

A Very Special Thanks To:
Carl Henderson
Dennis Salyer
Marty Genusa
Terry Surface
Steve Blankenbecler.

Very special thanks for winter observations also go out to Otis & Nancy Ward of Robinson Knob and to James & Carol Bolling and Cal Adams of Little Mountain ( adjacent to Big Cherry Lake ).

Of course, without any doubt, special thanks go out to ALL the photographers who contribute to this website, with very special thanks to my friend Roddy Addington for all the time he's spent amid the High Knob Massif in HARSH, winter conditions ( often with his buddy Bill Harris too ).  Thanks guys!

It is becoming well established that winter snowfall has a tendency to be heaviest within the Duplex portion of the massif.

Reference the following section of this website to learn what a duplex-imbricate system is:

Whitewater Rolls In High Knob Massif


Long Ridge of Tennessee Valley Divide
Gorgeous Silkmoth Species - June 28, 2011
Photograph by Wayne Riner - © All Rights Reserved.


June Rainfall Totals & 2011
Precipitation Totals From Across
Virginia & The District of Columbia
*( 2011 Totals from January 1 to June 30 )

Wallops Island
June Rainfall: 4.41"
2011 Precipitation: 14.74"

Great Dismal National Wildlife Refuge
June Rainfall: 2.33"
2011 Precipitation: 14.88"

Washington National Airport
June Rainfall: 1.68"
2011 Precipitation: 15.35"

Brookneal
June Rainfall: 1.98"
2011 Precipitation: 15.87"

Hampton 7.2 W
June Rainfall: 4.21"
2011 Precipitation: 16.16"
( 4 days missing during year )

Norfolk
June Rainfall: 4.63"
2011 Precipitation: 16.63"

Newport News
June Rainfall: 6.78"
2011 Precipitation: 16.65"

Farmville 2 N
June Rainfall: 1.03"
2011 Precipitation: 16.92"

Appomattox
June Rainfall: 2.64"
2011 Precipitation: 17.26"
( 5 days missing during year )

Danville
June Rainfall: 1.56"
2011 Precipitation: 17.52"

Buena Vista
June Rainfall: 1.58"
2011 Precipitation: 18.12"

Lynchburg
June Rainfall: 3.81"
2011 Precipitation: 18.61"

Chatham
June Rainfall: 1.95"
2011 Precipitation: 18.62"

Pulaski 2 E
June Rainfall: 1.53"
2011 Precipitation: 18.68"

Richmond
June Rainfall: 3.03"
2011 Precipitation: 18.86"

Washington Dulles Airport
June Rainfall: 1.40"
2011 Precipitation: 19.04"

Warrenton 5.5 SSE
June Rainfall: 1.65"
2011 Precipitation: 19.66"

Roanoke
June Rainfall: 3.51"
2011 Precipitation: 19.88"

  Martinsville Filter Plant
June Rainfall: 2.45"
2011 Precipitation: 20.15"

Lexington
June Rainfall: 2.86"
2011 Precipitation: 20.37"

Kerrs Creek 6 WNW
June Rainfall: 2.28"
2011 Precipitation: 20.67"

Covington Filter Plant
June Rainfall: 2.89"
2011 Precipitation: 20.68"

Staunton WTP
June Rainfall: 2.85"
2011 Precipitation: 20.96"

New Castle RAWS
June Rainfall: 1.94"
2011 Precipitation: 20.88"

Bland
June Rainfall: 1.15"
2011 Precipitation: 21.06"

Charlottesville
June Rainfall: 1.31"
2011 Precipitation: 21.41"

Sterling RCS
June Rainfall: 2.06"
2011 Precipitation: 21.50"

Wytheville 1 S
June Rainfall: 2.98"
2011 Precipitation: 21.61"

Waynesboro WTP
June Rainfall: 2.92"
2011 Precipitation: 21.91"
( 2 days missing March )

Painter 2 W
June Rainfall: 10.28"
2011 Precipitation: 21.97"

Gathright Dam
June Rainfall: 2.28"
2011 Precipitation: 22.64"

Holcomb Rock
June Rainfall: 2.78"
2011 Precipitation: 22.70"

Bluefield ( West Virginia )
June Rainfall: 1.81"
2011 Precipitation: 22.72"

Somerset
June Rainfall: 4.10"
2011 Precipitation: 22.90"

Trout Dale 3 SSE
June Rainfall: 1.41"
2011 Precipitation: 23.18"

Dale Enterprise
June Rainfall: 3.65"
2011 Precipitation: 23.45"
( 1 day missing February )

Blacksburg
June Rainfall: 2.78"
2011 Precipitation: 23.47"

Edinburg
June Rainfall: 3.43"
2011 Precipitation: 23.77"
( 1 day missing February )

Richlands
June Rainfall: 2.53"
2011 Precipitation: 23.96"

Radford 3 N
June Rainfall: 1.21"
2011 Precipitation: 24.35"

Galax Water Treatment Plant
June Rainfall: 3.15"
2011 Precipitation: 24.64"

Luray 5 E
June Rainfall: 3.32"
2011 Precipitation: 24.88"

Burkes Garden
June Rainfall: 3.29"
2011 Precipitation: 24.99"

Glasgow 1 SE
June Rainfall: 2.14"
2011 Precipitation: 25.41"

Saltville 1 N
June Rainfall: 2.99"
2011 Precipitation: 25.44"

Millgap 2 NNW
June Rainfall: 1.29"
2011 Precipitation: 25.51"

Christiansburg
June Rainfall: 2.83"
2011 Precipitation: 25.61"

Lebanon
June Rainfall: 3.19"
2011 Precipitation: 25.73"

Grundy
June Rainfall: 2.86"
2011 Precipitation: 26.04"

Marion 4.4 WSW
June Rainfall: 3.16"
2011 Precipitation: 26.04"
( 2 missing days March / 1 missing day May )

Woolwine
June Rainfall: 1.39"
2011 Precipitation: 26.07"

( Near VA-TN border )
Kyles Ford 1 N
June Rainfall: 3.22"
2011 Precipitation: 27.06"

Jonesville 3.1 WSW
June Rainfall: 3.88"
2011 Precipitation: 27.52"

Hot Springs
June Rainfall: 3.42"
2011 Precipitation: 27.90"
( 1 missing day January )

Nora 4 SSE
June Rainfall: 3.88"
2011 Precipitation: 28.27"

( Davis Vantage Pro2 )
Grayson Highlands State Park
June Rainfall: 2.65"
2011 Precipitation: 28.45"

Lebanon 2.7 SSW
June Rainfall: 5.09"
2011 Precipitation: 29.20"

Mustoe 1.2 SW
June Rainfall: 2.98"
2011 Precipitation: 29.50"
( 5 missing days during year )

Clintwood 1 W
June Rainfall: 6.25"
2011 Precipitation: 30.30"

Appalachia Lake Water Plant
June Rainfall: 6.92"
2011 Precipitation: 32.42"

Wise RAWS
June Rainfall: 6.64"
2011 Precipitation: 32.50"

Meadows of Dan 5 SW
June Rainfall: 5.39"
2011 Precipitation: 32.86"

Norton Water Plant
June Rainfall: 6.40"
2011 Precipitation: 34.52"

Robinson Knob of High Knob Massif
June Rainfall: 6.48"
2011 Precipitation: 35.95" ( M )

( South Fork Gorge )
Big Stone Gap Water Plant
June Rainfall: 6.59"
2011 Precipitation: 36.34"

Big Cherry Dam of High Knob Massif
June Rainfall: 6.16"
2011 Precipitation: 40.51" ( M )

( M ) - Denotes that total precipitation was greater than rain gage total due to evaporation between hand-measurements and physical gage losses in deep falls of snow.

*According to the latest Drought Status Report released on June 23, 2011 by the Virginia Drought Monitoring Task Force, the Statewide Observed Precipitation for the January 1 to June 24 period of this year averaged 19.47" ( -2.06" less than the Virginia average for that period ).  This was -20.34" less than observed at Big Cherry Dam up to June 24.



RING of FIRE
Brings Flash Flooding

June 20, 2011
Middlesboro, Kentucky Under Water
Photograph by Betty Jones - Courtesy of Jackson, Ky., NWSFO

Five days after I posted my June 15 update on this website the number one rated summer threat from the ring of fire became an unfortunate reality for the Middlesboro Basin and communities lying within a corridor of training, torrential rain producing thunderstorms.

Volatile Pattern Ahead Features RING OF FIRE

While Doppler radar tended to over-estimate rainfall due to hail and other factors, it clearly defined the main corridor of impact that simply hammered the southwestern half of Cumberland Gap NHP from which a gush of water roared with violent fury into sunrise on June 20.

Well Defined Corridor Of Training Thunderstorms
Image Courtesy of Plymouth State University Archive

Doppler radar estimated up to 15.60" of total rainfall over a 
4-day period ending on June 20, with the greatest rain gage tally reported being 8.73" from the Yellow Creek RAWS supported by the National Park Service ( two-thirds of that amount 
falling in just over 4 hours ).

This was a killer, destructive flash flood event that some residents said became the worst flood for Middlesboro in at least 50 years.

June 20, 2011
Middlesboro, Kentucky
Water Standing Long After Main Gush Of Flash Flooding
Photograph by Betty Jones - Courtesy of Jackson, Ky., NWSFO

Pictures submitted by Betty Jones & highlighted by the Jackson, Ky., National Weather Service Forecast Office were very impressive!

June 20, 2011
Middlesboro, Kentucky
Streets Transformed Into A Lake
Photograph by Betty Jones - Courtesy of Jackson, Ky., NWSFO

The corridor of thunderstorms responsible for this flash flood event would have created tragic results anywhere along the High Knob Landform or Mountain Empire, but could have been even worse locally had it been wide enough to severely impact the Martins Fork of the Cumberland River.

What many may take for granted is how truly dangerous and often random in placement such events are, with a mere 50-60 air miles making this a tragedy for Wise-Scott-Lee counties, for example, as imagine the results of this much rain falling upon, and becoming locally enhanced by, the High Knob Massif ( remnant high country mass of the High Knob Landform ).

While the Yellow Creek RAWS recorded 5.71" of rain in just 4.5 hours it is likely, given the typical undercatch of automated gauges in torrential rains, that more did fall overnight during this short period of time than reported by the gauge.

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