Sunday, May 9, 2010

HKL Spring Differences: Elevation + Latitude


May 3, 2010
Grindstone Dome of High Knob Massif
Photograph by Roddy Addington - © All Rights Reserved.

The High Knob Landform

Differences in spring conditions forced by elevation were captured by photographer Roddy Addington from Powell Valley Overlook on May 3, as dark greenery of late spring amid the lower Valley gave way to early spring conditions above the great band of calcareous cliffs ringing the High Knob high country. 

One of the truly wondrous aspects of the High Knob Landform is that it possesses both size and elevation ranges necessary for a grand display of large differences in seasonal transitions.

My friend Addison Stallard writes....
"In spring the mountain dresses from the bottom up.  The green begins outside our window; the maples in the field above show pink.  The green slowly creeps up the slopes and when it leaps over the cliffs, our spirits soar with it.........for then Spring has truly arrived, and if the Wood Thrush ( Hylocichla mustelina ) is not already on the hill behind the barn, she will not be far behind."

Upon climbing upward into the great massif, conditions suggested from the photograph above become distinct and widespread above 3000 feet.

May 6, 2010
Upper Tennessee River Basin
Special Biological Area of Jefferson National Forest
High Knob Lake Basin of Big Stony Creek Basin
Photograph by Roddy Addington - © All Rights Reserved.

Without a Lookout Tower it is not possible to truly illustrate the extent of conditions amid the high country, but an opening along a power line supplying High Knob Lake Recreation Area shows early spring conditions, with both bare trees and colorful maples!

May 6, 2010
High Knob Massif Crest Zone
Late Spring Between High Knob-Eagle Knob
Photograph by Roddy Addington - © All Rights Reserved.

Conditions visible up close, between High Knob and Eagle Knob, show that most trees are just now beginning to leaf out as some remain bare.

Its like stepping back in time to what conditions were like a month or so ago in lower elevations, and has always been one of my favorite aspects of spring amid the southern Appalachians. 

May 6, 2010
High Knob Massif Crest Zone
Early Spring Conditions In Late Spring
Photograph by Roddy Addington - © All Rights Reserved.

Current conditions in upper elevations of the High Knob Massif, as of May 6-7, are at a spring emergence point analogous to early-mid April within Powell Valley ( i.e., some 3 to 4 weeks ago ).

Lazy In The Valley - April 15, 2010
Photograph by Roddy Addington - © All Rights Reserved.

Early Spring In The Valley.

Inside The High Knob Landform
Majestic Powell Valley - April 16, 2010
Photograph by Roddy Addington - © All Rights Reserved.

GREEN-UP in Valley after recent flash flooding.

Powell Valley - May 3, 2010
Photograph by Roddy Addington - © All Rights Reserved.

Surrounded by high country the Valley typically "greens" some 2 to 4 weeks earlier than upper elevations of the High Knob Massif ( generally above 2700 feet ).

Differences between its highcountry and adjoining portions
of the Clinch River Valley in northern Scott County, Va., can be greater, but photographs are not readily available to illustrate them ( i.e., outside of the outstanding documentation my friend, photographer & naturalist Richard Kretz is doing within The Pinnacle NAP of the Clinch Valley in Russell County, Virginia ).

Forest Canopy Remains Open 
Above Clinch-Powell Valleys

High Knob Massif - May 6, 2010
Photograph by Roddy Addington - © All Rights Reserved.

Offers Multipe Peaks In Flowering

Furrowed Wakerobin ( Trillium sulcatum ) - May 6
Photograph by Roddy Addington - © All Rights Reserved.

Furrowed Wakerobin, also called Mountain Red Trillium, was in bloom below 3700 feet elevation on the chilly, wet, northern slopes of the High Knob Massif during May 6.

The large vertical elevation range ( and large size from SW to NE ) of the High Knob Landform provides an opportunity to catch multiple peaks in flowering, with different species unique to upper elevations being observed along with later bloomers common in the lower terrain.

Large-flowered Trillium ( Trillium grandiflorum ) - May 9
Photograph by Roddy Addington - © All Rights Reserved.

A single yet such beautiful example of multiple peaks in flowering can be illustrated by the simply wonderful Large-flowered Trillium, which is just now reaching peak bloom in the High Knob Massif.

Large-flowered Trillium Peaks:

Pinnacle Natural Area Preserve: April 10
North Fork of Pound Lake Area: April 11
Clintwood ( Cold Air Drainages ): April 15
High Knob Massif ( Around 3000 feet ): May 9

High Knob Massif - ( Trillium grandiflorum ) - May 9
Photograph by Roddy Addington - © All Rights Reserved.

Large-flowered Trilliums typically change into various shades of pink with age, and I consider them at peak when there is about an equal mix of bright white & pinkish trilliums in a family cluster.

My friend & photographer Roddy Addington estimated that he easily observed more than 1000 trilliums in glorious bloom during a Mother's Day journey along part of the High Knob Massif.

By contrast, as noted, my friend & naturalist Richard Kretz photographed Large-flowered Trilliums in peak bloom within The Pinnacle NAP of the Clinch Valley on April 10.

Wild Geranium ( Geranium maculatum ) - May 6
Photograph by Roddy Addington - © All Rights Reserved.

Cooler days amid higher elevations and chilly nights within the highcountry basins contribute to slower spring emergence despite the much wetter conditions and abundant moisture for growth.

Reference the following section of my website for a summary of precipitation totals within the High Knob Massif:


Differences between the foothills adjacent to the High Knob Landform were highlighted last month, and can again be illustrated by a summary of mean April conditions.

April 2010 Temperature Means

( Lower Elevations of Russell Fork Basin )
Clintwood 1 W - Elevation 1560 feet
Average Max: 73.2 degrees
Average Min: 37.3 degrees
Mean: 55.2 degrees

( Northern Base of High Knob Massif )
City of Norton - Elevation 2141 feet
Average Max: 68.8 degrees
Average Min: 37.2 degrees
Mean: 53.0 degrees

( Sugar Camp Mountain of Foothills )
Jackson, Ky., NWSFO - Elevation 1365 feet
Average Max: 73.8 degrees
Average Min: 50.8 degrees
Mean: 62.3 degrees

( Rolling Landscape West of Mountains )
London, Kentucky - Elevation 1211 feet
Average Max: 73.5 degrees
Average Min: 45.4 degrees
Mean: 59.4 degrees

In the High Knob high country April 2010 temps varied from 60s by day to low-mid 30s by night within the colder mountain basins.

High Knob Massif
Elevation near 3100 feet - May 9, 2010
Greater Yellow Lady's Slipper Orchid
( Cypripedium parviflorum var. pubescens )
Photograph by Roddy Addington - © All Rights Reserved.

Implications of the above are as previously noted during April, and as can be seen visually within all these wonderful photographs!

Pound Gap of Pine Mountain - April 18, 2010
Photograph by Roddy Addington - © All Rights Reserved.

The above view is looking into Virginia with 
the Kentucky side ( not visible ) being greener.

Even amid higher terrain along the VA-KY border, conditions in the Pound Gap section of Pine Mountain during mid-April were at an emergence point analogous to the current state above 2700 feet in the High Knob highcountry.


Current Comparison On Mother's Day

Head of High Knob Lake Basin - May 9, 2010
Image by Steve Blankenbecler - © All Rights Reserved.

My friend Steve Blankenbecler submits a image to further illustrate that conditions are still a long way from reaching summer maturity within High Knob Lake Basin, at elevations above 3500 feet.

North Slopes High Knob Massif - May 9, 2010
Image by Steve Blankenbecler - © All Rights Reserved.

Even northern slopes of the High Knob Massif between 3000 and 3500 feet elevation have a way to go, as the above image illustrates well, before they green up to look like Pine Mountain ( below ).

Birch Knob of Pine Mountain - May 9, 2010
 Photograph by Roddy Addington - © All Rights Reserved.

Birch Knob of Pine Mountain is the highest peak in Dickenson County, Va., with a summit elevation of 3149 feet above sea level.  Although all trees have leafed out, it will be a little longer before those along the crest reach summer maturity.

Capping the entire middle horizon of this photograph is a portion of the High Knob Massif with its long, rising swell of high country extending outward to join the jagged, undulating crestline of its northwestern mountain arm ( called Little Stone Mountain ).

Visible toward far right is the northeastern end
of the heavily strip mined Black Mountains.


**Updated - COLD May Temperatures

Cold conditions will slow growth observed in the above images, with upper 20s occurring at the summit level of the High Knob Massif during Mother's Day morning ( generating 6+ hours of below freezing conditions and LOWER wind chills on May 9, 2010! ).

Even colder temps developed into the predawn hours of May 10 with a combination of light winds and unseasonably low ( dry ) dewpoint air over upper elevations supporting it's subsequent drainage into higher mountain valleys.

Frosty upper 20s to lower 30s were common in mountain valleys at 4 a.m., Monday, as readings continued to drop!  By contrast, temps along the mountain ridges were in the mid-upper 30s.

Minimums - May 10, 2010
( elevations 1560-2450 feet )

City of Norton: 29.5 degrees
Clintwood 1 W: 30.7 degrees
Wise ( in town ): 31.9 degrees

Morning minimums of 25 to 30 degrees were common within colder mountain valleys of the sprawling High Knob high country, including drainage into the Norton-Coeburn valley corridor 
( the coldest 24 to 28 degree MINS occurring in lofty high country basins of the massif resting at 2400 to 3600 feet above sea level ).

Reference the following sections for a listing of favored cold air pockets ( basins ) within the High Knob highcountry:

Flora 2: Wildflowers of The High Knob Landform

Autumn Color 2009 - HKL

This generated a hard freeze with 4-10 hours of sub-freezing conditions depending upon the locale.

High Knob Massif ( Elevation near 3100' ) - May 9, 2010
Mayapple ( Podophyllum peltatum )
Photograph by Roddy Addington - © All Rights Reserved.

Woodland wildflowers of the southern Appalachians are very hardy, with most species being climatized to withstand spells of sub-freezing conditions ( species & blooming adjusted over time to fit the exposure, soil type, elevation, and latitude
of their site locations ).

Occasionally, as noted below, there are extreme events in which even the most hardy suffer freeze damage!

Valleys in lower elevations, below 1500 feet, were generally above freezing within the surrounding region ( far southwestern Virginia & southeastern Kentucky ).

Minimums - May 10, 2010 
( lower elevations below 1500 feet )

Hurley: 33.0 degrees
Clinchco: 33.8 degrees
Sandlick: 34.2 degrees
Grundy: 34.0 degrees
Whitesburg, Ky., 35.0 degrees
Skyline, Ky., 36.0 degrees
Hazard, Ky., 38.0 degrees

Awesome Photograph
( Air at dewpoint in morning chill )
Grindstone Dome of High Knob Massif - May 13, 2010
Photograph by Roddy Addington - © All Rights Reserved.

The first half of May....
May 1-15, 2010 Temperature Means

( Lower Elevations of Russell Fork Basin )
Clintwood 1 W - Elevation 1560 feet
Average Max: 78.2 degrees
Average Min: 45.5 degrees
Mean: 61.8 degrees
Lowest Temp: 31 degrees

( Northern Base of High Knob Massif )
City of Norton - Elevation 2141 feet
Average Max: 72.8 degrees
Average Min: 45.0 degrees
Mean: 58.9 degrees
Lowest Temp: 29 degrees

( Sugar Camp Mountain In Foothills )
Jackson, Ky., NWSFO - Elevation 1365 feet
Average Max: 76.1 degrees
Average Min: 55.5 degrees
Mean: 65.8 degrees
Lowest Temp: 38 degrees

( Rolling Landscape West of Mountains )
London, Kentucky - Elevation 1211 feet
Average Max: 77.1 degrees
Average Min: 53.6 degrees
Mean: 65.4 degrees
Lowest Temp: 36 degrees

In the High Knob high country May 1-15 temperature means varied from 60s by day to 
40-45 degrees by night in colder mountain basins 
( the lowest May temps being mid-upper 20s ).

Mean nightly lows during the first half of May, in higher mountain valleys within and adjacent to the High Knob Massif, have generally been as cool or cooler than those observed amid the Kentucky foothills during the previous month of April.

The above being another excellent example of why there are such large differences in spring green up across the area, with Mother Nature over time setting the biological clock of the highcountry backwards to in effect state, "if you come out too early, you will be frozen!"


Historical May Climatology
Coldest May Temperatures On Record

Early Summer 2002
Freeze Damage In High Knob Lake Basin
Photograph by Wayne Browning - © All Rights Reserved.

Lingering freeze damage from a historic May 2002 cold wave was still visible during early summer within the High Knob Lake Basin, as noted above, and was widespread in drainages of the much larger Big Cherry Basin.

It can still get cold during May, especially if there is a rare snow.  Such was the case on May 6-7 in 1989, when 2" to 4"+ stuck from Clintwood to Norton, Wise, and across the High Knob Massif.

Written May 1989...
"The snow, which intensified around dawn, made early morning on May 7 look like a mid-winter blizzard.  The mountains & hollows greeted dawn in an unsurpassed display of eloquent beauty!

Adhesive snow crystals intermingled with a spectrum of hues representative of the early spring forest to create a silhouette filled with such majesty that even the Creator himself must have paused to ponder the magnificence of it all."

More often than not, however, May coldness is not associated with snowfall but late season surges of unseasonably cold, dry air masses from Canada.

Coldest Official May Temperatures In Wise ( 1956-2009 )
May 2, 1963....24 degrees
May 3, 2005....27 degrees
May 6, 1957....27 degrees
May 10, 1966...27 degrees
*May 8, 1989...28 degrees
May 4, 2004....29 degrees
May 7, 1968....29 degrees
May 14, 1996...29 degrees
May 22, 2002...29 degrees 

( * ) - Came in wake of 3.3" of snowfall.

The coldest temperatures officially recorded on the Wise Plateau, at around 2550 feet above sea level, are applicable to exposed middle elevation locations of Wise & Dickenson counties. 

Coldest May Temps In Burkes Garden ( 1896-2009 )
May 5, 1986....19 degrees
May 15, 1910...19 degrees
May 10, 1947...20 degrees
May 4, 1986....21 degrees
May 8, 1925....21 degrees
May 11, 1947...21 degrees
May 27, 1925...21 degrees
May 6, 1910....22 degrees
May 9, 1947....22 degrees

The coldest official temperatures recorded in Burkes Garden, at an elevation of 3300 feet, are applicable to the colder upper elevation mountain basins ( providing an idea of what conditions may have been like amid the lofty basins of the High Knob high country during past years prior to any temperature recording in the massif ).

Standing out in the Burkes Garden data set are great May cold waves during 1925 and 1947.

The greatest May cold wave of prolonged nature occurred in 2002, when 7 new record mins 
( 4 by night and 3 by day ) were established in both 
Wise and Burkes Garden.

May 18-22, 2002 --- Historic Cold Spell
( from my climate archive )

"Temperatures plunged into the upper 30s in Wise prior to dawn on May 18, and held there into mid afternoon as a historically long period of record breaking cold settled into the Appalachians.

The unusally long-lived period of cold temperatures damaged gardens, orchards and vegetation as record low temperatures were set by both day and night.

In fact, freeze damage browned so many trees that some places looked more like autumn than late spring!

Minimum readings amid the colder mountain drainges reached the lower to middle 20s during the period.

All total, seven new low temperature records were set in Wise during the five day period!"

The most severe hitting May freeze of recent note, and historic impact, turned mountain forests of the High Knob Massif into a blaze of brown and black during May 2005 ( especially below 3500 feet, where the most trees had leafed out ).

MAJOR Freeze Damage - High Knob Massif - May 2005
 Photograph by Wayne Browning - © All Rights Reserved.

"The most widespread and extensive freeze damage in local memory," is how the May 2005 event was described after long time residents like Addison & Elizabeth Stallard ( in Powell Valley ) and Otis & Nancy Ward ( in Robinson Knob ) verified that it was truly of historic nature. 

Mountain forests across the High Knob Massif did not recover from its impact until late June and early July 2005 ( widespread brown trees making late spring and early summer look more like autumn following color fade.  An incredible sight like nothing I had ever seen in my life! ).

*A Golden Rule: The first night following a cold frontal passage is typically colder upon mountain ridges and exposed plateaus, while the second night becomes colder within adjacent mountain valleys.  Although not always the case, of course, it is more often than not a golden rule that holds true.

**Other chilly May nights within colder mountain basins of the High Knob Massif included upper 30s to lower 40s on May 5, and middle 30s-lower 40s on May 7 ( during 2010 ).


Size Matters - Latitude Is A Factor Too

The large size of the High Knob Landform ( HKL ) also allows latitude to play some role in speeding spring green-up toward the southwestern end of the HKL ( from near the VA-TN border to I-75 ).

Fern Lake & Middlesboro Basin - April 25, 2010
Photograph by Roddy Addington - © All Rights Reserved.

Majestic Fern Lake and the Middlesboro Basin sit some 2300 vertical feet lower in elevation than the High Knob Lake Basin, such that elevation is the major player.

Cumberland Gap National Historical Park - April 25
Photograph by Roddy Addington - © All Rights Reserved.

Latitude also plays some role, since this part of Cumberland Gap NHP rests 64 air miles SW of its remnant massif ( i.e., the High Knob high country ).

Looking Across Southern Lee County - April 25
Photograph by Roddy Addington - © All Rights Reserved.

The water level of Norris Lake, Tn., at 1020 feet, lies 3203 vertical feet lower than the peak of High Knob.  This southwestern most extent of the HKL is more than 108 air miles southwest of Guest River Gorge, at its northeastern end in Virginia.

These amazing facts are all part of 
the name and purpose of this website:
Wilderness Road State Park - April 25, 2010
Photograph by Roddy Addington - © All Rights Reserved.

The lofty backbone of great Cumberland Gap NHP, with its dual Cumberland-Brush Mountain confluence, creates a rugged and truly gorgeous backdrop for Wilderness Road State Park, and also possesses enough elevation range to accentuate seasonal differences within the vertical.

Although much more narrow than the sprawling High Knob highcountry, and lower in elevation, the high terrain spreading outward at the confluence of Cumberland and Brush mountain's gives birth to what are likely the two most pristine whitewater creeks in all of Kentucky.

Martin's Fork ( a state designated Wild River ) and Shillalah Creek, which collectively drain a large area of remote wilderness within & adjoining Cumberland Gap National Historical Park along this simply wonderful NW mountain arm of the HKL ( i.e., the geological NW flank of the Powell Valley Anticline ). 

Wilderness Road State Park - Lee County, Virginia
Photograph by Roddy Addington - © All Rights Reserved.

Although this sweeping mountain landscape of the HKL offers very distinct climatic differences throughout the year, they always seem to be most notable ( and much anticipated ) during the major seasonal transitions between winter-summer 
( spring ) and summer-winter ( autumn ). 

Majestic Shillalah Creek - Cumberland Gap NHP
Photograph by Harold Jerrell - © All Rights Reserved.

Although the above differences have been unconsciously known and taken for granted over the years, this is the first time that a website has documented them in such a visual way.

It is also, of course, the first time that a website has been created to specifically highlight and document the natural world of the great High Knob Landform.
  

Unique Orographics
Revealed In Air Flow

Morning Roll Clouds & Waves: 7 AM on May 7, 2010
Photograph by Roddy Addington - © All Rights Reserved.

Unique mountain generated rolls & waves were captured by photographer Roddy Addington in the early morning light of May 7, as low-level moisture was forced to rise upward along nearly vertical walls of the High Knob Massif. 

What makes the above scene rather unique being that there were clear skies aloft, with the stacked rolls and waves developing as air near the surface cooled to its dewpoint to reveal previously invisible moisture.

The morning featured a simply huge temperature contrast, with 35 to 45 degree readings in colder mountain valleys being in dramatic contrast to 50s and low 60s across mid-upper elevation ridges and plateaus exposed to SSE-SW winds. 


Dramatic Sunrise & Sunset

Along The Tennessee Valley Divide
Golden Spring Morning - May 6, 2010
Photograph by Wayne Riner - © All Rights Reserved.

A nice way to open or close any HKL website update is by featuring the glory of our mountain sunrises & sunsets!

Flag Rock Recreation Area
Beautiful Fish-Tail Mountain Wave Clouds
Sunset Across The High Knob Landform
Photograph by Beckie Roberts - © All Rights Reserved.

Lets all say a big...WOW!

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