Saturday, November 3, 2012

Historic Winter Storm of October 2012


October 30, 2012 ( 8:47 AM )
Long Ridge of Tennessee Valley Divide
Blizzard Conditions & Drifting Across Highlands
Photograph by Wayne Riner - © All Rights Reserved.

Many winter storms have been worse.

Deeper Snow.  Bigger Drifts.  
Colder Temperatures.

But none on record had ever been worse in

October!

October 30, 2012
Powell Valley Overlook of High Knob Massif
Beauty In The Beast - Red Maple Leaf Rests
Photograph by Roddy Addington - © All Rights Reserved.



Superstorm Sandy

Super Rapid Scan Imagery ( 6-Day Life Cycle )
Courtesy - University of Wisconsin-Madison
Please Reference CIMSS For More Information

Super High Resolution Rapid Visible Scans
of Sandy during 6 days ( nights are dark ).

Please select the Change Quality button to 1080p HD 
for best viewing in FULL Screen Mode ( Hit ESC to return ).

This is the first time that a former Hurricane has dumped a significant amount of SNOW upon the southern-central Appalachians ( in modern times ).

As far back as October 1898, John Fox Sr., of Big Stone Gap, recorded in his weather log that snow covered High Knob above 2900 feet elevation during October 21-23 ( no depth noted ).  It is common 
to have October snowflakes and accumulations on 
High Knob, but not like observed during this event!

October 28, 2012 at 3:04 PM
Eagle Knob of High Knob Massif Communications Area
Image by Steve Blankenbecler - © All Rights Reserved.

October 31, 2012 at 1:10 PM
Eagle Knob of High Knob Massif Communications Area
Image by Steve Blankenbecler - © All Rights Reserved.

The most severe conditions in the High Knob Massif developed along the main crest zone, from Bowman Mountain and Eagle Knob southwest over the High Knob peak and across Big Cherry Basin to Thunderstruck Knob.  Conditions got so bad that residents adjacent to Big Cherry Lake were still stranded by 4 foot snow drifts and downed trees into afternoon hours of November 7. 

Just South of Laney Cemetery ( Scott County )
Deep Snow Accumulation On State Route 619
Image Courtesy of Tim Peters & WCYB Photo Archive
( Around 1,000 vertical feet below main summit )

Many public reports indicated snow depths varied from 1 to 4+ feet, with waist to chest high depths in drifting common from High Knob & Camp Rock across Big Cherry Basin.  The largest snow drifts were estimated to have been up to 8 feet prior to significant settlement and melting.

It is rather amazing that snow could even get this deep given an above freezing ground and continuous melting beneath the snowpack ( at least during much of the event ).

Just West of High Knob In Harlan County
Deep Snow On Big Black Mountain, Kentucky
Image Courtesy of Charlie Huff & WCYB Photo Archive

Deep snow depths were common along windward & lofty lee slopes from the High Knob Massif into 
Big Black Mountain and adjacent Pine Mountain, which collectively featured the greatest snowfall amounts in Virginia & Kentucky during this event.

( 5 Miles from University of Virginia's College In Wise )
20" Snow Depth - Coeburn Mountain of Wise Plateau
Image Courtesy of Dakota Cantrell & WCYB Photo Archive

That conditions remained bad in exposed high elevations into early November is shown by this photograph submitted by JoAnna Hobbs, which appears to be from the Apple Orchard section of 
Big Black Mountain ( near Virginia-Kentucky stateline ).

November 2, 2012
( Apple Orchard Section Near Stateline )
Deep Snow On Big Black Mountain in Harlan County, KY
Photograph Courtesy of JoAnna Hobbs to WCYB Photo Archive

Without a dozer or large snow plow to open the road, is it little wonder that some folks could still not get out of the High Knob Massif ( November 7 ).

General snow depths in hardest hit sections of the massif, from High Knob into Big Cherry Basin, were reportedly around or above ATV tires during the peak of this event.  ATV's could only make it so far before getting bogged down in deeper drifts ( i.e., snow depths were generally too great for extended ATV travel ).

October 31, 2012
Heavy Rime Formation In High Knob Massif
Photograph by Bill Harris - © All Rights Reserved.

High winds plus heavy riming from days spent amid clouds in sub-freezing air only added to these wintry problems, with drooped limbs and many broken branches & trees reported.

October 31, 2012
( Windward Side of Branches )
Classic High Knob Massif Rime Growth
Photograph by Bill Harris - © All Rights Reserved.

Snowfall amounts & depths were especially elevation dependent during this event, with location + elevation working together to generate greatest amounts along and just leeward of slopes and crestlines facing W-NW air flow trajectories. 

Least amounts, by contrast, were found both at lowest elevations and also downstream of major mountain barriers like the High Knob Massif and Tennessee Valley Divide ( * ).

*Big Black Mountain and the Cumberland Mountain arm of the High Knob Landform both being part of the Tennessee Valley Divide ( as is the Wise Plateau to Long Ridge of Sandy Ridge & Hazel Mountain to Big A Mountain-Jewell Ridge corridor ).

October 31, 2012
No Snow In The Powell River Valley
Cumberland Mountain Arm of High Knob Landform
White Rocks of Cumberland Gap National Historical Park
Photograph by Harold L. Jerrell - © All Rights Reserved.

A major problem for thousands again became power outages, with 1050 homes still amid darkness in Dickenson County as late as the morning hours of November 2.

A total of 1050 homes represents a significant number of people within a rural county like Dickenson ( down from more than 5000 homes & businesses in darkness at the peak of this episode ).

Personal communication with an AEP field worker told me that electricity was restored to the last home in Dickenson County on November 4 ( 6 days after it had went out ).

Many thanks have to be extended to AEP, ODP, and VDOT workers who again endured rough conditions to get the job done.



History of Superstorm Sandy
Daily ECMWF Model Initializations

Click consecutively on images for motion

European Model 
850 MB & Surface Charts

8:00 AM on October 23, 2012

8:00 PM on October 23, 2012

8:00 AM on October 24, 2012

8:00 PM on October 24, 2012

8:00 AM on October 25, 2012

8:00 PM on October 25, 2012

8:00 AM on October 26, 2012

8:00 PM on October 26, 2012

8:00 AM on October 27, 2012

8:00 PM on October 27, 2012

8:00 AM on October 28, 2012

As blue colors invaded ( i.e., cold air ) on October 28 rain changed to snow, with a general 2" to 4" of accumulation across upper elevations in the High Knob Massif.

( Scroll down to )

8:00 PM on October 28, 2012

The main storm event developed late on October 29 into October 30 as Sandy made landfall and moved inland, with ROARING high elevation winds and blizzard conditions in heavy snow and blowing snow along the upslope side of the southern and central Appalachians.

8:00 PM on October 29, 2012

Wind gusts of 20 to 40 mph were common across middle elevations, between 2000 and 3000 feet, during October 
29-31, with much stronger winds above 3000 feet.  

8:00 AM on October 30, 2012

8:00 AM on October 31, 2012

Strong winds above 2500 to 3000 feet made determining how much snow actually fell very difficult during this event, with blowing snow and widespread drifting causing large depth variations.

Otis Ward reported that sustained ROARING of winds were about as loud as he had ever heard through the overnight hours and into sunrise on October 30.  When he started outside 2 feet 
of snow was blown up against his front door, with larger drifts ( estimated at 4 to 6 feet ) in the area 
( Otis & Nancy Ward have lived in the Robinson Knob community since April 1974 ).

October 30, 2012
Example from Long Ridge of Tennessee Valley Divide
Blowing & Drifting Snow In The Middle Elevations
Photograph by Wayne Riner - © All Rights Reserved.

High winds during this period likely caused much snow to miss the home of Joe & Darlene Fields in High Chaparral, long-time snow observers, with a snow depth only near a foot ( 16-17" total fall ).

The greatest departure in High Chaparral, verses other locations, was observed during the period of strongest winds into morning hours of October 30 ( suggesting wind was the main factor ).

Such local variations have been observed in past high wind settings, with High Chaparral located near gaps in the head of Burns Creek of the Guest River just east of the crest zone.

October 30, 2012
Wind Swept Garden Amid October Winter Storm
Photograph by Wayne Riner - © All Rights Reserved.

While 30 to 40 mph gusts were common amid middle elevations, between 2000 & 3000 feet, gusts to Hurricane Force buffeted upper elevations.

An extreme example was reported by weather observer Landis Wofford, where the high-tech measuring equipment mounted in the lofty gap on Grandfather Mountain's famous Swinging Bridge clocked peak gusts up to 105 mph 
( CAT 2 hurricane force ).


European Model
500 MB & Surface Charts

8:00 AM on October 23, 2012

8:00 PM on October 23, 2012

8:00 AM on October 24, 2012

8:00 PM on October 24, 2012

8:00 AM on October 25, 2012

8:00 PM on October 25, 2012

Follow the phasing process as the green-blue colors denoting Polar Jet Stream winds absorb Hurricane Sandy over time, with hybrid to extratropical BOMBogenesis transformation amid a strong left hook forced by high latitude blocking to the north.

8:00 AM on October 26, 2012

8:00 PM on October 26, 2012

8:00 AM on October 27, 2012

8:00 PM on October 27, 2012

8:00 AM on October 28, 2012

8:00 PM on October 28, 2012

8:00 PM on October 29, 2012

8:00 AM on October 30, 2012

8:00 AM on October 31, 2012



Historical Rank 
of Superstorm Sandy

October 30, 2012
Snowy View From Powell Valley Overlook
Photograph by Roddy Addington - © All Rights Reserved.

An additional 3" to 6" of new snow fell above 3000 feet in the High Knob Massif between 8:00 PM October 30 and 8:00 AM October 31 ( a "big" snow by October standards ).

Superstorm Sandy is now the benchmark snowfall event against which all future October falls of snow will be measured by in the southern & central Appalachians of the USA!

However, despite this fact, Superstorm Sandy can not locally match the following great events which all produced more total snowfall, deeper mean depths, larger snow drifts, and MUCH colder temperatures ( with a couple of temp exceptions** ).

March 1942 Blizzard
( Benchmark Snow Depth Event )

November 1950 Blizzard
( Great Thanksgiving Storm & Depth Rival )

February 1985 Blizzard
( HUGE Snow Drift Event )

April 1987 Mega-Spring Storm
( DEEP fall over 72-hours )

March 1993 Superstorm
( The Complete Package )

January 1996 Snowstorm
( Deep Snow Producer )

January 1998 Snow Blitz
( Record 24-Hour DUMP & Power Outages )

Mega-Disaster Storm Of 2009 ( And January 1998 )

December 2009 Mega-Disaster
( Massive Power Outages & Depth )

**The January 1998 and December 2009 storm events were isothermal monsters, with relatively deep layers near freezing resulting in massive power outages.

October 30, 2012
Powell Valley Overlook
Beauty Amid The October Beast
Photograph by Roddy Addington - © All Rights Reserved.

Many other winter storms have been as bad or worse than Superstorm Sandy during winter and spring months, but never during the mid-autumn month of October ( with a few lower elevation leaves ).

October 30, 2012
Lingering Leaves At Powell Valley Overlook
Photograph by Roddy Addington - © All Rights Reserved.

The Halloween Storm of October 1993 was the former record holder, in modern times, with snowfall totals that varied from 4" to 6" in the Clintwood-Wise area up to 9" on High Knob.

Superstorm Sandy shattered those records!

October 30, 2012
Wise County, VA of the USA
October Winter Wonderland
Photograph by Roddy Addington - © All Rights Reserved.


Snow depth variations across the area 
and region were huge during this event.



Snow Depth Statistics
Superstorm Sandy

***High Knob Peak to Big Cherry Lake
1.5 to 2.5 Feet
( Drifts of 4 to 8 Feet )

High Chaparral-Robinson Knob to Flat Gap
1 to 1.5 Feet
( Drifts of 2 to 4 Feet )

Wise Plateau to Long Ridge
 10" to 20"+
( Drifts To Waist or Higher )

Clintwood ( In & Around Town )
4" to 10"
( Minor Drifting Below 2000 feet )

Grundy
1" 
( Official Depth In Town )

Silver Leaf-Rose Hill of Lee County
Trace

Tri-Cities, Tennessee
Trace
( Official Storm Total )


***High Knob Reports From The Wise County EMS Manager

1130 AM     SNOW             2 S NORTON           36.90N 82.63W
10/30/2012  M24.0 INCH       WISE            VA   EMERGENCY MNGR


0200 PM     SNOW             2 S NORTON           36.90N 82.63W
10/31/2012  M30.0 INCH       WISE            VA   EMERGENCY MNGR

HIGH KNOB


[ The update on October 31 corresponded to a general 3" to 6" of measured new snowfall from High Chaparral to High Knob and Little Mountain between 8 PM October 30 and 8 AM October 31 ].

( Due to strong winds the above is only generalized as local depth variations actually ranged from near bare ground to FEET in drifts within mid-upper elevation sites most severely impacted ).



Snow Core Data
( November 6, 2012 )

Due to the historic nature of this October fall of snow I have devoted more time to try and better determine how much snow really fell atop the 
High Knob Massif Crest Zone.

Several factors made this event 
difficult to measure:

1 ).  High winds & widespread drifting
( e.g., severe rain gauge undercatches )

2 ).  Early season fall on unfrozen ground
( e.g., enhanced sub-surface melting & settlement )

3 ).  Extended snowfall from October 28-31 .
( e.g., more time for impacts on depth )

A general cycle of melting by day and freezing 
at night was observed during the October 31 to November 6 period, with sub-freezing night temps verses days that averaged around 40 degrees at the summit level ( 30s by day were likely in the mean on shady north slopes at these higher elevations* ).

*Overnight-morning periods of November 2 and November 4 remained above freezing on exposed crests.

Afternoon hours of November 6 found a solid snowpack above 3000 to 3200 feet elevation along the main crest zone, with snow covering all of the High Knob Lake Basin and the Big Cherry Lake Basin for as far as could be seen from the 
High Knob peak area.

Measurements taken between Chestnut Flats 
and Camp Rock found 3" to 12" of snow depth remaining, with a general 6-12" at the highest elevations.  Local snow drifts remained above 
2 feet, and over top ATV's, along Forest Service Route 237 which remained blocked amid the Davenport Gap Drift Zone.

Snow Core Data
November 6, 2012 at 1715 hours
Little Mountain Knob of High Knob Massif
Elevation 4057 feet At Core Site
0.4 air mile SSE of High Knob Peak 
( 166 vertical feet lower than main peak )
Snow Core of 11” of depth ( clean snow )
Melted Water Content: 2.66”
Snow Density of 4:1
( 0.24" of water per 1" of snow )

( Little to no additional precipitation fell at 
the core site following this October Blizzard ).

A snow core on 11" of snow depth yielded 2.66" of water content.  The core was taken in an opening away from trees in order to help minimize the impact of rime drop which tends to add significant amounts of moisture to snowpacks amid the 
High Knob Massif ( in the forest under trees ).

Rime is a product of moisture deposition of supercooled water droplets in sub-freezing air upon above ground objects like trees, often amid windy regimes in orographic cloud layers capping the massif.  It grows into the wind over time.  

It is confused by those lacking knowledge of rime with HOAR frost that is more commonly seen at low elevations as a product of condensation of water vapor in light wind settings.  Rime does not form in dry air advection regimes ( increasing dewpoint depressions ) at mid-upper elevations but can sometimes develop as freezing fog, under special conditions, and be observed at low elevations as a different type of rime from that driven by orographic forcing.


Many links on this website illustrate rime


What Does The Snow Core Mean?

Post-Storm Core Data
( Recent Major Event Examples )
Selected for their WET falls of snow

January 1998
Snow Core 3 Days After Event
Yielded 92% of Original Fall Value
( No additional precipitation )

December 2009
Snow Core 8 Days After Event
Yielded 64% of Original Fall Value
( 0.59" of additional precipitation )

( Mega-Disaster Snowstorm of December 2009 )

Snow core water content tends to become more dense over time in the wake of major storm events, with more water observed per 1" of snow than occurred at the time of the main event.

Snow density increases over time as water in the snow core 
becomes more concentrated per 1" of snow.

In addition, unless there is much additional moisture input, processes such as sublimation, melting, and evaporation tend to decrease total water content in snow cores over time from their initial storm total value.

Without significant added moisture input, total water held in snow cores decreases over time due to processes that extract moisture irrespective of increasing snow core densities.

In examples from two major winter storm episodes in 1998 and 2009, snow cores taken 3 to 8 days after the events held from 92 to 64 percent, respectively, of their original storm total fall values.

Note that these examples are for single storm events.  During prolonged periods of time with multiple snow, or rain and snow events, and rime deposition episodes there tends to be increases in total water content of snowpacks in the High Knob Massif.

While an exact value for the initial core can not be known, a rough estimate based upon these two examples would be that it held around 78% of its original value ( being 6 days removed from the storm event with no major moisture inputs ).

Estimate Of Total Fall Value
( In Liquid Water Content )

2.66" / 0.78 = 3.41"
( approximate 9:1 snow density )

Adding 0.35" of rainfall measured 
prior to the transition to snow gives:

3.41" + 0.35" = 3.76" Storm Total Fall
( for the Eagle Knob to Little Mountain Knob area )

Reviewing data from this event suggests this is a good estimate.  If no moisture was lost from the core up until late on November 6, an unrealistic assumption, the storm total would be 3.01" when adding rain that fell prior to the snow 
( i.e., the estimate above assumes only 0.75" was lost in 
6.5 days from the core via extractive processes such as sublimation, melting & evaporation ).

The above is certainly conservative when considering this was an October fall of snow, and the ground was warmer than during the two snow core example events.

Looking at storm values from lower elevations northwest of the massif, this would correlate to a zone of heavier precipitation documented by the Jackson, Ky., NWS Forecast Office.


This correlates well with reported snow depths to suggest that total snowfall did reach or exceed 30" near the summit level of the High Knob Massif during this October 28-31 event.

An added supporting factor was a 22" decrease in mean snow depth on Mount LeConte, at 6400 feet in Great Smoky Mountains National Park, between 7:30 AM October 31 and 7:30 AM November 6 
( with 1" of new snowfall ).

Snow depths on High Knob should have decreased more than the colder Mount LeConte site, but IF they only diminished the same amount it would have yielded 25" to 34" of general snow depth 
( based upon my measurements on November 6 ) at the peak of this event, with MUCH larger drifts as were well documented.

Folks blocked from getting out of Big Cherry Basin of the High Knob Massif for 10 DAYS by DEEP snow do not doubt these impressive numbers!

Perhaps just as impressive is the fact that only 30 or so air miles S-SE of the massif there was only 0.61" of total precipitation measured at TRI ( Tri-Cities, Tennessee ), including just a trace of snow!

That's a MAJOR WOW!



Snow Density And
Rain Gauge Undercatches

Wind Speed Verses Rain Gauge Catch

It has long been known that rain gauges do not catch all the precipitation that falls, with increasing rain gauge losses as wind speeds increase at gauge height.  These losses being much greater for frozen precipitation than for rainfall.

It has been estimated, as illustrated above, that there can be 70 to 80 percent gauge loss on snow 
( especially ) as mean wind speeds reach 12 to 16 mph at the top of the rain gauge.

The reality for very windy locations like upper elevations in the 
High Knob Massif is that no rain gauge that is unshielded will ever 
be able to capture the true significance of orographic forcing season precipitation.  It would take a combination of snow cores on each snow event and highly shielded gauges in select places to obtain what could be termed "accurate" data that is close to what actually falls to the ground.  The greatest obstacle I've faced.

It is hard to calculate snow density using only rain gauge data during events like Superstorm Sandy.

Assuming all gauges at higher elevations had loss, and looking at vertical temperature profiles of the storm, it appears that Superstorm Sandy possessed at least a couple of notable snow density patterns.

1 ).  A regional pattern with latitudinal variations.

2 ).  A local pattern with elevation variations.


Regional Snow Density Pattern

The coldest air in Superstorm Sandy was found over the Mountain Empire, with milder air to the northeast such that snow densities tended to increase from the High Knob Massif toward Canaan Mountain in northern West Virginia.

In a simplistic way this can be seen by following the evolution of the storm on NAM Model charts, even without studying vertical temperature profiles, by watching the 850 MB temperature pattern on the upper left chart at each time period.

Click Consecutively On The Charts For Motion

NAM Model Charts For 8:00 AM - October 28, 2012

NAM Model Charts For 8:00 PM - October 28, 2012

NAM Model Charts For 8:00 AM - October 29, 2012

NAM Model Charts For 8:00 PM - October 29, 2012

NAM Model Charts For 8:00 AM - October 30, 2012

NAM Model Charts For 8:00 PM - October 30, 2012

NAM Model Charts For 8:00 AM - October 31, 2012

During the bulk of this event, as noted, 850 MB temperatures were colder in the vicinity of the Virginia-Kentucky border than the West Virginia-Maryland border.  This caused snow density to increase northeastward from far southwestern Virginia and to produce more severe damage.

Snow densities were high amid all locations and elevations during this event, however, a snow density gradient did exist with a latitudinal increase toward the northeast along the Appalachians ( amid the region that received significant amounts of accumulating snowfall ).


Local Snow Density Pattern

A local snow density pattern featured the wettest snow at lower elevations, below 2500 to 3000 feet, where more leaves on trees combined with this wettest snow to make power outages most widespread in nature.

An analogous pattern to January 1998 and December 2009 but with less severe damage as a whole, for most places ( still a huge pain for folks out of electricity, as is very well understood! ).

Wayne & Genevie Riner obtained a 7:1 snow density during the 24-hour period ending on the morning of October 30, at Nora 4 SSE on Long Ridge, with an 11:1 density during the next 24-hour period. High winds and drifting making it difficult to figure at this middle elevation site of 2650 feet.

While snow remained wet to the summit level 
of the High Knob Massif, density appeared to decrease a little with the estimated 3.41" of snow water equivalent producing around 30" or a little more of total snowfall ( as previously highlighted ).

Air temperatures held generally in the 20s during this event at the summit level of High Knob.  In contrast, it was hard for elevations below 1600 feet to reach freezing during the event with the result being only 1" of snow in downtown Grundy and a trace along the Powell River Valley of Lee County.

Because snowfall below 1600 feet was limited by temperature, the greatest damage zone locally ended up being within the 1600 to 2600 foot elevation zone.  More snowfall but generally less damage occurred above 2600 to 3000 feet.

Heavy rime formation from days spent amid sub-freezing cloud vapor contributed to more damage in upper elevations of the High Knob Massif than did snow, which was generally blown off trees by high winds during the main event period.

Because strong positive forcing with this event 
( upsloping ) was compensated for by strong inverse, or negative, forcing ( downsloping ) leeward of the High Knob Massif - Tennessee Valley Divide, snowfall was further limited in the Tri-Cities area of the Great Valley of northeastern Tennessee.  

It was not until air was again lifted by the secondary Appalachian front range ( the TN-NC 
border area with respect to WNW-NW air flow ) that significant amounts of snow again developed ( with an elevation step-up necessary to get into heaviest amounts along the windward slopes ).

A notable increase in snow northeast of downtown Bristol, toward Abingdon, being due largely to the decrease of downsloping leeward of the High Knob Massif, where NW air flow trajectories can stream across lower terrain into the Great Valley ( missing the main crest zones of the High Knob Massif - Black Mountain corridor ).

An interesting and repeated aspect of 
Mountain Empire winter season climatology.  
Forecaster's TAKE NOTE!



A Missing Ingredient 
Superstorm Sandy

October 30, 2012
Long Ridge of Tennessee Valley Divide
Drifts Observed Amid Break In Heavy Snow
Photograph by Wayne Riner - © All Rights Reserved.

As bad as Superstorm Sandy was during October, at least one important missing weather ingredient prevented it from actually producing much more snow and BIGGER drifts.  MUCH more!

Cold air...especially ALOFT.

Cold air was not just lacking at lowest elevations in this storm but also aloft, with vertical temperatures above Wise on the morning of October 30 showing colder conditions at 800 MB than at 700 MB.

This lack of steep lapse rates, or strong vertical temperature drops with increasing height, actually held powerful orographic forcing in check and prevented Sandy from developing conditions like observed during the Superstorm of March 1993.

While a benefit of colder air would have been a reduction in snow density and possible power outages, the trade off would have been a great increase in both snowfall amounts and drifting.

Steep vertical lapse rates would have not only increased lift and rising air along the mountains but also the production of a snow in which each 1.00" of water equivalent would have yielded much more snowfall.  Much more!

Since high density snow is also hard to drift, this would have greatly increased drifting via a drier, lower density snow amid the colder air.

So as bad as it was, "it could have been much worse" to steal a line from philosophy!



Climate Statistics
For October 2012

October 30, 2012
Long Ridge of Tennessee Valley Divide
Month Of Major Transition - Flowers To Deep Snow!
Photograph by Wayne Riner - © All Rights Reserved.

( Lower Elevations of Russell Fork Basin )
Clintwood 1 W - Elevation 1560 feet
Average Daily MAX: 63.4 degrees
Average Daily MIN: 39.5 degrees
MEAN: 51.4 degrees
Highest Temperature: 78 degrees
Lowest Temperature: 32 degrees
Total Precipitation: 3.66"
Snowfall: 7.0"
2012 Precipitatioin: 39.02"

( Northern Base of High Knob Massif )
City of Norton - Elevation 2141 feet
Average Daily MAX: 61.0 degrees
Average Daily MIN: 37.2 degrees
MEAN: 49.1 degrees
Highest Temperature: 78 degrees
Lowest Temperature: 28 degrees
Total Precipitation: 4.58"
Snowfall: 12.0"
2012 Precipitation: 59.55"

( Wise Plateau of Tennessee Valley Divide )
Wise 3 E - Elevation 2549 feet
Average Daily MAX: 61.8 degrees
Average Daily MIN: 43.7 degrees
MEAN: 52.8 degrees
Highest Temperature: 81 degrees
Lowest Temperature: 29 degrees
Total Precipitation: 3.35"
Snowfall: 17.5"
2012 Precipitation: 50.42"

( Along Tennessee Valley Divide )
Nora 4 SSE - Elevation 2650 feet
Average Daily MAX: 59.5 degrees
Average Daily MIN: 44.5 degrees
MEAN: 52.0 degrees
Highest Temperature: 77 degrees
Lowest Temperature: 27 degrees
Total Precipitation: 3.89"
Snowfall: 13.4"
2012 Precipitation: 40.41"

In the High Knob Massif, above 2700 feet, mean October temps varied from 50s by day to 30s at night ( lower 40s on exposed ridges ).

Autumn colors were brilliant with the most vivid hues observed during the September 26-October 10 period, while peak colors extended through 
mid-October at lower elevations.

Autumn Color Changes In 2012

Autumn Color 2012 - A Vivid Season

The precipitation regime ended up being dominated by an early season snowstorm of historic nature, and high winds, such that rain gauge undercatches were severe at higher elevations ( especially above 3000 feet ).

Using snow core data with rainfall that was measured generates 6.20" of total water equivalent precipitaton for October in the Eagle Knob, High Knob, and Little Mountain Knob area ( i.e., basin heads for High Knob Lake, Big Cherry Lake, and the Norton Reservoirs ).

Otis & Nancy Ward reported 4.20" during October in Robinson Knob, but the undercatch on their rain gauge was figured to be at least 1.00" to 1.25" during Superstorm Sandy alone.

This brings their raw rain gauge total to 60.27" for 2012.  Significant rain gauge losses which occurred amid deep falls of snow, in February 2012 and now October 2012, not being included.

October 30, 2012
Red Maple ( Acer rubrum ) Leaves Upon Deep Snow!
Photograph by Roddy Addington - © All Rights Reserved.



( Updated On November 10, 2012 )
Seasonally Cold Start
To November 2012

November 4, 2012
Lower Elevations of Cumberland Mountains
The Towers Rock Formation In Breaks Interstate Park
Photograph by Roddy Addington - © All Rights Reserved.

Majestic Breaks Gorge is often the last place to reach peak color during autumn across the northeastern end of the Cumberland Mountains, with frequent fog formation along the Russell Fork River and its lower elevations, such that multiple peaks can often be captured in many autumns by starting in upper elevations of the High Knob Massif and working 
downward into middle and lower elevations 
( following the color changes ). 

November 2012 has opened seasonally cold with lingering impacts of Superstorm Sandy being especially notable across upper elevations of the High Knob Massif - Black Mountain corridor, as discussed above, where snow can still be seen.

( Route 237 remained blocked by snow drifts into November 7 
in Big Cherry Basin of the High Knob Massif ).

Lingering snow over the high country has indirectly impacted adjacent valleys, where frosty cold nights have ruled the opening third of November 2012 .

( First Third of November )
City of Norton - Elevation 2131 feet
Average Daily MAX: 47.4 degrees
Average Daily MIN: 25.3 degrees
MEAN: 36.4 degrees

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