Wednesday, April 16, 2014

Season Of Transformation In The HKL


April 15, 2014
Wilderness Road State Park
Powell River Basin of High Knob Landform
Majestic Mid-April Contrast Of Spring & Winter
Photograph by Harold L. Jerrell - © All Rights Reserved.


Capped by upslope clouds and snow the rugged, cliff-laden expanse of Cumberland Mountain created a dramatic backdrop for photographer Harold L. Jerrell to capture this season of transformation in the High Knob Landform.

Wilderness Road State Park

April 15, 2014
Wilderness Road State Park
Rugged Cumberland Mountain Rises Into Clouds
Photograph by Harold L. Jerrell - © All Rights Reserved.

Spring comes earlier to valleys around Wilderness Road State Park than it does to the high country of Cumberland Gap National Historical Park ( NHP ), resting above the cloud-shrouded cliffs of these photographs and this panorama.

HKL Spring Differences - Elevation + Latitude
Changes in both latitude & elevation ( up to 3200+ vertical feet ) can make dramatic differences in spring emergence along the
High Knob Landform ( HKL ).

April 15, 2014
Lee County, Virginia
NW Flank of Powell Valley Anticline
Panorama At Wilderness Road State Park
And Cloud-Shrouded Cumberland Gap NHP
Photograph by Harold L. Jerrell - © All Rights Reserved.

Cumberland Gap National Historical Park

This same great band of cliff and cave forming rocks of Mississippian Age Greenbrier Limestone, that 40 miles ENE rings much of the remnant high country mass of the High Knob Landform, stood boldly out against spring snow and greening valleys of the Powell River Basin in both Lee & Wise counties of southwestern Virginia.

Distance Between Photo Views & High Knob Massif
Google Earth Display of High Knob Landform

In the High Knob Massif this great band of calcareous cliffs mark a climatic change zone and are often capped by clouds and majestic rime during the cold season and fog at warmer times.

Wise County, Virginia
( Where NW-SE Flanks Join )
SE Flank of Powell Valley Anticline
High Knob Massif Archive Photograph
The Same Band of Cliffs Ringing Powell Valley
Photograph by Roddy Addington - © All Rights Reserved.

Rod Addington Photography

It should be no surprise that this also seems to be the case 40-50+ miles WSW along this landform, where these same jagged cliffs also mark a zone above which conditions often tend to be much different than below these spectacular outcrops!

April 15, 2014
Wilderness Road State Park
( Cumberland Gap NHP In Distance )
Majesty Of Spring In The Cumberlands
Photograph by Harold L. Jerrell - © All Rights Reserved.

Eastern Redbud ( Cercis canadensis var. canadensis ) trees are abundant over calcareous soils throughout the Powell & Clinch river watersheds of the Upper Tennessee River Basin.

While colorful Redbud trees are eye-catching, the stars of this early spring emergence show are an array of woodland wildflower beauties like the appropriately named "Spring Beauty." 

April 14, 2014
Lovelady Gap of High Knob Landform
Spring Beauty ( Claytonia virginica )
Photograph by Harold L. Jerrell - © All Rights Reserved.

Some of these species have not been "officially" documented for Wise, Scott, and Lee counties of the High Knob Landform; however, proof of their existence is in Harold's beautiful photographs.

April 14, 2014
Lovelady Gap of High Knob Landform
Squirrel Corn ( Dicentra canadensis )
Photograph by Harold L. Jerrell - © All Rights Reserved.

The 1" to 3" of snow and unseasonable cold of 
April 15-16 likely did not diminish these hardy early bloomers, with snow accumulations being mostly above their current blooming elevations.

April 14, 2014
Lovelady Gap of High Knob Landform
Squirrel Corn ( Dicentra canadensis )
Photograph by Harold L. Jerrell - © All Rights Reserved.

The first Large-flowered Trilliums ( Trillium grandiflorum )
were just beginning to bloom on April 17 in cold air drainages
of the Russell Fork Basin and will likely not peak at mid-upper elevations in the High Knob Massif until late April or May.

April 11, 2014
White Branch Gorge of High Knob Landform
Southern Red Trillium ( Trillium sulcatum )
Photograph by Harold L. Jerrell - © All Rights Reserved.

A nice photograph featuring 
a variety of different species.

April 11, 2014
White Branch Gorge of High Knob Landform
Rue Anemone ( Thalictrum thalictroides )
Southern Red Trillium Trillium sulcatum )
Yellow Trout Lily ( Erythronium americanum )
Photograph by Harold L. Jerrell - © All Rights Reserved.


Huge Conditions Contrast
Differences Along The Mountains
During April 15, 2014

CAM Elevation 2600 feet
April 15, 2014 at 1:22 PM
Looking Toward The High Knob Massif
University Of Virginia's College At Wise
Courtesy of Computer Science-Mathematics Department

Elevation played a big role in conditions during April 15 with a general 1-3" of snow accumulating above 2000 feet elevation along and north of the High Knob Massif and Tennessee Valley Divide 
( this included the NW Flank of the High Knob Landform containing upper elevations of Cumberland Gap National Historical Park ).

This can be illustrated by images at 
the same time but in different locations.

April 15, 2014 at 12:13 PM
Approach To Cumberland Gap From Kentucky
Photograph by Harold L. Jerrell - © All Rights Reserved.

April 15, 2014 at 12:13 PM
Looking Toward The High Knob Massif
University Of Virginia's College At Wise
Courtesy of Computer Science-Mathematics Department

April 15, 2014 at 2:08 PM
Valley Floor At Wilderness Road State Park
Photograph by Harold L. Jerrell - © All Rights Reserved.

April 15, 2014 at 2:09 PM
Looking Toward The High Knob Massif
University Of Virginia's College At Wise
Courtesy of Computer Science-Mathematics Department

Large differences were also observed between 
western and eastern sides of the Appalachians.

April 15, 2014 at 4000 feet
Just SE of Tennessee Valley Divide
Grayson Highlands State Park At 3:02 PM
Image Courtesy of Friends of Grayson Highlands SP

April 15, 2014 at 2650 feet
Just NW of Tennessee Valley Divide
Long Ridge of Sandy Ridge At 2:59 PM
Photograph by Wayne Riner - © All Rights Reserved.

April 15, 2014 at 4000 feet
Along Leeward Side of Blue Ridge Mountains
Grayson Highlands State Park At 4:16 PM
Images Courtesy of Friends of Grayson Highlands SP

April 15, 2014 at 4:16 PM
Looking Toward The High Knob Massif
University Of Virginia's College At Wise
Courtesy of Computer Science-Mathematics Department

April 15, 2014 at 4:22 PM
Amid The Great Valley Between The Mountains
Cumberland Square Park In Bristol, Virginia
Live CAM Images Courtesy of Weatherbug

April 15, 2014 at 4189 feet
Along Windward Side of Cumberland Mountains
Eagle Knob of High Knob Massif At 4:55 PM
Photograph by Steve Blankenbecker - © All Rights Reserved.


Climate Statistics
Early-Mid April
( April 1-17, 2014 )

( Lower Elevations of Russell Fork Basin )
Clintwood 1 W - Elevation 1560 feet
Average Daily MAX: 67.8 degrees
Average Daily MIN: 35.5 degrees
April 1-17 MEAN: 51.6 degrees
Highest Temperature: 83 degrees
Lowest Temperature: 23 degrees

( Northern Base of High Knob Massif )
City of Norton - Elevation 2141 feet
Average Daily MAX: 63.7 degrees
Average Daily MIN: 34.0 degrees
April 1-17 MEAN: 48.8 degrees
Highest Temperature: 79 degrees
Lowest Temperature: 19 degrees

( Along the Tennessee Valley Divide )
Nora 4 SSE - Elevation 2650 feet
Average Daily MAX: 63.5 degrees
Average Daily MIN: 42.4 degrees
April 1-17 MEAN: 53.0 degrees
Highest Temperature: 77 degrees
Lowest Temperature: 21 degrees

April 16, 2014 at 12:26 PM
Widespread Snow Across N Slopes of Massif
University Of Virginia's College At Wise
Courtesy of Computer Science-Mathematics Department

One of the most impressive early-mid April aspects was the general 60 degree temperature change observed during April 13-16, centered around 
April 15 snow, with even greater differences felt when factoring in significant wind chills. 

April 15, 2014 at 4:26 PM
Long Ridge of Tennessee Valley Divide
Apple Blossoms Covered By Spring Snow
Photograph by Wayne Riner - © All Rights Reserved.

Wayne Riner Photograph Thoughts...
"Late spring snowfall has covered some of our apple blossoms.  Hopefully, because the blooms 
are still closed, the fruit may not be damaged."

January-March of 2014
Precipitation Departures Across USA

A drier than normal pattern dominated April 1-17 
to continue a trend observed since the beginning of 2014, with the notable local exception of February which had near to above average precipitation.

April 1-15, 2014
Northern Hemisphere
850 MB Air Temperature Composite Anomalies

The first half of April was also warmer than average, despite the shocking temperature plunge that produced accumulating snow across higher elevations on April 15.

April 15, 2014
Cumberland Gap Campground Road
Cumberland Gap National Historical Park
Photograph by Harold L. Jerrell - © All Rights Reserved.

A climatologic constant becoming more distinct during early-mid April was the thermal belt, which in the High Knob Massif - Tennessee Valley Divide corridor is that zone within which average night-time temperature MINS are milder than locations both above and below its elevation range.

The 42.4 degree average MIN observed at Nora 4 SSE on Long Ridge ( at 2650 feet ) was 8.4 degrees milder than the 34.0 degree average MIN on the floor of the Norton Valley ( at 2141 feet ) and some 6 degrees milder than the average MIN near the summit level of the High Knob Massif ( at 4200 feet ).

For More Information:
Scroll Down To The Thermal Belt In This Section

No comments:

Post a Comment