Saturday, September 19, 2009

Wet Summer Across The HKL In 2009

Little Stony Gorge of High Knob Massif ( Middle Falls )
Photograph by Richard Kretz - © All Rights Reserved.

The High Knob Landform

Climate Statistics for August
And Summer 2009

August continued the wet and cool trend of Summer 2009 with an especially CHILLY July being a notable aspect of this season in the southern Appalachians.

A few statistics for selected locations included:

Dickenson County

Elevation 1560 feet
( Lower Elevations of Russell Fork Basin )
Clintwood 1 W
Average Summer Max: 78.1 degrees
Average Summer Min: 57.6 degrees
Mean: 67.8 degrees
August Rainfall: 4.14"
Summer Rainfall: 18.52"
2009 Precipitation: 39.69"

Elevation 2650 feet
( Along the Tennessee Valley Divide )
Nora 4 SSE On Long Ridge
Average Summer Max: 75.4 degrees
Average Summer Min: 60.7 degrees
Mean: 68.0 degrees
August Rainfall: 3.75"
Summer Rainfall: 15.88"
2009 Precipitation: 36.73"

Wise County

Elevation 1945 feet
( Grindstone Ridge Base of High Knob Massif )
Head of Powell Valley
August Rainfall: 5.27"
Summer Rainfall: 17.27"
2009 Precipitation: 45.36"

Elevation 2342 feet
( Northern Base of High Knob Massif )
City of Norton Water Plant
August Rainfall: 5.19"
Summer Rainfall: 18.60"
2009 Precipitation: 49.30"

Water Elevation 2360 feet
( Northwest Mountain Flank of High Knob Massif )
Appalachia Lake Water Plant
August Rainfall: 6.99"
Summer Rainfall: 18.57"
2009 Precipitation: 49.37"

Water Elevation 3120 feet
( High Knob Massif Crest Zone )
Big Cherry Dam of High Knob Massif
August Rainfall: 7.08"
Summer Rainfall: 20.94" ( M )
2009 Precipitation: 52.51" ( M )

Elevation 4178 feet
( High Knob Massif Crest Zone )
Eagle Knob of High Knob Massif 
Average Summer Max: 69.4 degrees 
Average Summer Min: 56.4 degrees
Mean: 62.9 degrees
Max Temp: 78 degrees on June 19
Min Temp: 47 degrees on June 6, July 19

( M ) - Indicates missing moisture due to evaporation
between hand-measurements of the NWS rain gauge.

Average summer maximums remained in the 60s across the upper northern and eastern slopes and highest elevations of the High Knob Massif, with not a single day during the season breaking 80 degrees on the Eagle Knob of High Knob ( with good exposure to insolation at 4178 feet above mean sea level ).

This implied that mid-upper 70s were the best summer could generate amid the shady northern slopes at highest elevations of the massif.

An average nightly minimum of 56.4 degrees on Eagle Knob also meant that most nights in lofty basins of the High Knob high country had temps dipping into the 50 to 56 degree range 
( via cold air drainage off the crestlines ).

The above being rather typical for summer MIN temperatures in mid-upper elevation basins with low-mid 50s, for example, also being observed for MEAN minimums during the June-August period of Summer 2008. 

The above is why camp fires & blankets felt so good to backcountry hikers and those enjoying designated recreation areas at majestic High Knob Lake, Bark Camp Lake, and Flag Rock. 

Ah, summer in the high country!

High Knob Meadow - Elevation 4223 feet
Looking Across Big Cherry Basin of High Knob Massif
Photograph by Wayne Browning - © All Rights Reserved.

Rainfall extremes for the June-August period of summer varied from 12.47" in Grundy to as much as 24.00" in wettest portions of the High Knob Massif ( along the Wise-Scott-Lee border area ).

A hand-measured rainfall total of 20.94" at Big Cherry Dam of the High Knob Massif by my friend Gary Hampton, Superintendent of the South Fork Gorge ( Big Stone Gap ) Water Plant and his staff, was one of the greatest reported in the entire region despite missing moisture due to evaporation between measurements ( 0.31"+ of evaporation from the rain gauge just during June ).