21 February 2025
Deep Snow and Rime
Eagle Knob of High Knob Massif
Cody Blankenbecler Image © All Rights Reserved
February 2025 has been wicked!
Everything from ice and snow storms to thunderstorms, high winds, and significant, damaging flash flooding and river flooding.
A general 11.00" to 12.00" of total precipitation have been hand-measured along the base of the High Knob Massif from the City of Norton to
Big Stone Gap, with up to 15.00" at the
summit-level of the massif.
What a month!
2 February 2025
Snow Drifts On High Knob Peak
Cody Blankenbecler Image © All Rights Reserved
The month started mild with a big rain event that continued to diminish the deep snowpack which developed during January.
2 February 2025
High Knob Massif
Snowy Head of High Knob Lake Basin
Cody Blankenbecler Image © All Rights Reserved
*Observe many downed trees from hurricane Helene
across the above view (much worse on other slopes).
A total of 3.13" of rain were measured at the
Big Stone Gap Water Plant in the South Fork of Powell River gorge during January 30-February 1, with locally 4.00" to 5.00" at upper elevations in the High Knob Massif.
2 February 2025
Northern Slope of High Knob Massif
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This triggered high water and minor flooding, with the snowpack reduced to only northern slopes at highest elevations.
A few days of mild, dry conditions gave way
to a super-active pattern during February 5-21,
with one system after another pounding the
mountain landscape.
Significant Rainfall Event
(February 6-7, 2025)
Another significant rainfall event centered on February 6 developed in advance of the first
winter storm of the month.
Doppler Radar Rainfall Estimate
A general 2.00" to 3.00"+ of rain fell within
upslope locations of the High Knob Massif area.
This once again pushed creeks to high levels, with super-saturated conditions on the surface and within subterranean caves and conduits.
This event gave way to a notable cooling trend.
High-Country Rime Event
(February 9-10, 2025)
Low clouds banked against the western front range and foothills of the Appalachians during February 9-10 in advance of a developing winter storm (reference satellite images).
9 February 2025
High-Resolution Satellite Imagery
9 February 2025
High-Resolution Satellite Imagery
9 February 2025
High-Resolution Satellite Imagery
A significant rime event developed across
upper elevations of the High Knob Massif.
10 February 2025
High Knob Lookout
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10 February 2025
High Knob Massif
Big Cherry Lake Basin In Background
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This majestic array of rime added additional water to this already saturated (now freezing) mountain landscape.
10 February 2025
High Knob Massif
Looking Across Grindstone Ridge
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Snow-Ice Storm
(February 11, 2025)
A total of 4" to 5" of dense snow gave way to a damaging ice storm across upper elevations of the High Knob Massif during February 11, with a general 0.3" to 0.5" of ice accumulation.
11 February 2025
Damaging Ice Storm
Along Route 238 on High Knob
Cody Blankenbecler Photograph © All Rights Reserved
This brought more trees down and knocked power out in the Eagle Knob Communications Complex.
11 February 2025
High Knob Massif
Ice Accumulation On Eagle Knob
Cody Blankenbecler Photograph © All Rights Reserved
11 February 2025
Elevation 4196 feet
Ice Accumulation On Eagle Knob
Cody Blankenbecler Photograph © All Rights Reserved
Significant Flood Event
(February 15-16, 2025)
Additional significant precipitation on following days reached a climax during February 15-16 with widespread flash flooding and river flooding.
January-February 2025
Daily Observations
City of Norton Water Plant
Data Courtesy of Andrew Greear & Staff
February 2025
Daily Observations
Big Stone Gap Water Plant
Data Courtesy of Gary Hampton & Staff
(Measured at the Big Stone Gap WP)
(From my Dickenson Star Weather Column)
"A general 3.00" to 6.00"+ of rain generated widespread flooding, with moderate to major flooding observed on the Russell Fork river at Haysi, portions of the Pound river, the Guest River at Coeburn, and lower reaches of the Clinch, Powell, Cumberland and Levisa Fork rivers.
More than 150 state roads were closed in Wise, Scott, Lee, Dickenson, and Buchanan counties by Saturday afternoon into early Sunday. Many structures and roads were damaged."
February 11-17, 2025
Precipitation Totals
The High Knob Massif was positioned along an
axis of heaviest rainfall during the week ending February 17, with the massif having the highest elevations into which SSW to SE air flow was
lifted (as detailed later, this was important).
The February 1-16 precipitation total reached 14.85" on Eagle Knob, more than 2200 vertical feet higher in elevation than the Big Stone Gap WP (*).
*This would be among the highest February totals ever documented in Virginia (14.37" at Big Cherry Lake Dam during February 2018 was the previous local record and all-time state record for Virginia).
15 February 2025South Fork of Powell River
**Overflow From Big Cherry Lake DamVideo Courtesy of Gary Hampton
Despite having the dam spillway completely
closed, overflow from Big Cherry Lake basin
was tremendous by the afternoon hours
of Saturday (February 15, 2025).
**Communities such as Cracker Neck, East Stone Gap, and Big Stone Gap would have been in serious trouble if Big Cherry Dam had not been present to hold back a great amount of run-off (even though conditions were certainly bad enough, it would have been much more severe).
It amazes me how much water this landform can hold, with a combination of dams, wetlands, and subterranean conduits all being major factors for water retention (as noted later). Perhaps the most important factor is intact forests, which greatly reduce run-off versus logged-fragmented forests.
Mainstem River Levels
Headwater rivers draining the High Knob Landform and Cumberland Overthrust Block reached moderate-to-major flood levels.
Russell Fork of Big Sandy River
Pound River Above Indian Creek
Pound River Below Bold Camp Creek
Pound River At Norland (Dickenson County)
Guest River At Riverview (Coeburn)
Clinch River Near Speers Ferry
Clinch River Above Tazewell, TN
Powell River Near Jonesville
Powell River Near Arthur, TN
Cumberland River At Pineville, KY
Cumberland River At Williamsburg, KY
Levisa Fork At Pikeville, KY
Tributary Rivers-Streams
Flash flooding on tributary, headwater creeks and rivers reached minor-to-moderate levels across the mountain area (*).
*If the same amount of rain had fallen on the Russell Fork basin as fell across the High Knob Massif, flash flooding and river flooding would have been much more severe.
High Knob Massif dams at Bark Camp Lake,
Big Cherry Lake, High Knob Lake, City of Norton Reservoirs, Appalachia Lake and Rimrock Lake (northwestern arm) helped reduce direct run-off into headwater creeks and rivers.
Cranes Nest River Near Clintwood
The presence and benefit of middle-upper elevation wetlands, such as those in The Glades (Glady Fork of Big Stony Creek) and Wolf Creek (Laurel Fork of Stock Creek) should also not be discounted for their water retention abilities in these settings.
Big Stony Creek (Fort Blackmore)
Subterranean conduits, some associated with major
cave systems, also acted as sources of underground
water storage until they completely filled to overflow.
South Fork of Powell (Big Stone Gap)
A near fatal event was fortunately prevented
by the Bristol Swift Water Rescue Team when a vehicle was swept away by the North Fork of Clinch River near Duffield.
The occupant was found stranded on top
of the vehicle and rescued by the Team.
North Fork of Clinch River (Duffield)
Wallen Creek At Pennington Gap
The flood event ended with a general 1-2" of snow below 3000 feet, with 2-3" across upper elevations above 3000 feet.
17 February 2025
Eagle Knob of High Knob Massif
Winter Majesty In Wake Of Flood
Cody Blankenbecler Image © All Rights Reserved
17 February 2025
Winter Majesty In Wake Of Flood
Cody Blankenbecler Image © All Rights Reserved
Winter Storm & Bitter Air
(February 19-21, 2025)
The next winter storm came in two
phases during the February 19-21 period.
18 February 2025 Eagle Knob of High Knob MassifCody Blankenbecler Image © All Rights Reserved
A fast moving southern stream system dropped
a general 2-4" of snow during February 19.
19 February 2025
Eagle Knob of High Knob Massif
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This was followed by an upper-level low and N-NW flow snowfall during February 20 into early hours of February 21.
20 February 2025
Eagle Knob of High Knob Massif
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Storm snowfall totals reached 4" to 6" below 3000 feet, with 6" to 10" across the high-country above 3000 feet.
21 February 2025
Eagle Knob of High Knob Massif
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Minimum temperatures dipped to near and below zero degrees at upper elevations, above 3000 feet, with widespread sub-zero wind chill factors.
21 February 2025
High Knob Massif
High Knob Lookout
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21 February 2025
High Knob Massif
Snow-Rime Laden Northern Slopes
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21 February 2025
High Knob Massif
Snow-Rime Laden Northern Slopes
Cody Blankenbecler Image © All Rights Reserved
Winter Precipitation Difference
(Incredible Contrast Across Mountain Empire)
An absolutely incredible difference has been observed during Winter 2024-25 between the
High Knob Massif area and the Great Valley of northeastern Tennessee.
Total Precipitation
(December 1-February 16-17)
City of Norton Water Plant: 21.95"
Big Stone Gap Water Plant: 22.15"
Eagle Knob of High Knob Massif: 29.23"
Air Mile Distance
Eagle Knob to Tri-City Airport
A total of 9.60" of precipitation have been officially measured at Tri-City Airport since the beginning of Meteorological Winter (1 December 2024).
(As of February 22, 2025)
NWS Precipitation Totals
Tri-City Airport, TN
This is not only much less than observed during February 1-16 in the City of Norton to Big Stone Gap corridor, it is incredibly less than the 29.23" reported on Eagle Knob since the start of Meteorological Winter (***).
***This includes missing data in frozen precipitation. Totals of 22.00" to 23.00" have been hand-measured along the base of the High Knob Massif (City of Norton and Big Stone Gap water plants) since the beginning of Meteorological Winter.
The difference in winter snowfall totals has been even more stunning, with 7.9" at Tri-City Airport versus 81.00" on Eagle Knob (despite only a 31.4-air mile difference between the two sites).
The elevation difference between Eagle Knob and
Tri-City Airport is 2677 feet (4196 versus 1519 feet).
The 2024-25 winter season is currently tied for the 12-snowiest of the past 32-winter seasons at lower elevations (below 2000 feet) northward of the High Knob Massif (where northerly air flows are forced to rise upward toward the high terrain).
Lower Elevations
Clintwood 1 W NWS (#)
(Snowfall In Inches)
#The elevation at Clintwood 1 W is approximately
the same as at Tri-City Airport in NE Tennessee.
Extreme precipitation differences continue when comparing the High Knob Massif area with the New River Valley, Roanoke Valley, and locations east of the mountains in the Virginia Piedmont.
NWS Precipitation Totals
NWSFO Blacksburg, Virginia
The notable difference here is that both the New River and Roanoke valleys are running well above their longer-term averages for precipitation, while Tri-City Airport has received below average precipitation.
NWS Precipitation TotalsCity of Roanoke, Virginia
NWS Precipitation Totals
City of Danville, Virginia
These west-to-east precipitation differences across Virginia, and the Great Valley, are common. Many have been highlighted during the past 16-years.
February Air Flow Trajectory
(Mean Orographic Forcing)
What made February 2025 so very
wet in the High Knob Massif area?
Vector Wind
February 1-20, 2025
925 MB Composite Mean
Part of the reason is related to the mean air flow trajectory, with a SSW inflow into the High Knob Massif through the wide open expanse of the
Great Valley of eastern Tennessee.
Vector Wind
1948-2020 Mean (72-Year)
925 MB Annual Composite
February 2025 flow was analogous to the mean annual, long-term air flow trajectory at 925 MB (near elevation of Wise) which helps make the High Knob Massif area the wettest in Virginia.
There is nothing downstream as
elevated as the High Knob Massif.
Air Flow Trajectory And Terrain
The mean-layer 850 mb-Surface vector anomaly was essentially identical to this flow, meaning that the bulk of heavier rainfall (in this case) was being forced to rise across the 3000-4000+ foot terrain of the massif with limited downstream moisture extraction in the lower atmosphere.
850 MB to Surface
February 1-20, 2025
Vector Wind Layer Composite Anomaly
The 925 MB vector wind composite anomaly was also favorable for efficient lifting and convergence along the massif from the southeast (and river valleys of the Clinch and Holston).
Vector Wind
February 1-20, 2025
925 MB Composite Anomaly
Majesty Of Winter
(Winter Season 2024-25)
Winter can truly be a season of
exceptional beauty and majesty.
Ice Crystals
Amazing Hoar Frost
Jessica Bier & Wayne Browning_iPhone
Complex Waves And Ice Patterns
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Delicate Hoar Frost Formations
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Incredible Ice Formations
Jessica Bier_iPhone Photograph
Finger Ice Formations
Jessica Bier_iPhone Photograph
Horse-hoof Ice Formations
Jessica Bier_iPhone Photograph
Frozen In Time
Jessica Bier & Wayne Browning_iPhone
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