Tuesday, October 22, 2013

Autumn Scenes From 2013


October 20, 2013
High Knob Massif
A City of Norton Park & Natural Wonder
Autumn Color Peak In Flag Rock Recreation Area
Photograph by Roddy Addington - © All Rights Reserved.


Gorgeous blue skies decorated the mountain landscape following a frosty cold morning amid mountain valleys and the first deposition of light rime formation upon upper elevations in 
the High Knob Massif.

October 20, 2013
Upper Elevations of High Knob Massif
Ferns Outlined By Icy Deposition of Water Vapor
Photograph by Roddy Addington - © All Rights Reserved.

Low clouds continued to hang over upper elevations, above 3000 feet, as temperatures dropped below freezing during predawn hours of October 20 ( with clearing via dry air advection leaving only river valley fog in place by sunrise ).

( Temperatures In Degrees Fahrenheit at 8:00 AM )
NASA Visible Image At 8:32 AM - October 20, 2013

A little Pre-Holiday Decoration?

October 20, 2013
Upper Elevations of High Knob Massif
First Deposition of Moisture From Cloud Vapor
Photograph by Roddy Addington - © All Rights Reserved.

Morning hours of October 21 featured coldest conditions in mountain valleys of the great Cumberland Block, with widespread 25 to 30 degrees reported around Norton, Tacoma, Coeburn, and from Jonesville to Clintwood 
( only thermal belt locations being temporarily spared ).

This little bit will, of course, be nothing compared to what coming days will bring as unseasonably cold, upslope winds blow a taste of true winter 
into the western front range of the Appalachians.

October 20, 2013
Color Peaks On The Ground
City of Norton - Flag Rock Recreation Area
Photograph by Roddy Addington - © All Rights Reserved.

Friday ( October 25 ) continues to look like the coldest day of this upcoming blast, with temperatures remaining below freezing in upper elevations and struggling amid mostly 30s in middle elevations ( 2000-3000 feet ).

Even lowlands around Big Stone Gap & Fort Blackmore, which should be much "milder," will feel dang COLD!

Although flakes could fly before Friday at high elevations, the best timing on widespread snowflake action and even accumulations looks to be Thursday Night into Friday morning.  This will be the period to watch to see how LOW sticking snow levels can go?

October 20, 2013
Powell River Watershed
Benges Basin of High Knob Massif
New Spillway At The Upper Norton Reservoir
Photograph by Roddy Addington - © All Rights Reserved.

This anomalous hit of early winter will, of course, be nothing compared to the historic snow blitz delivered just over one year ago by the great and powerful Superstorm Sandy.

Heavy Snow & Drifting
Historic Winter Storm Of October 2012

( Scroll Down To "Storm Of A Lifetime" Section )
Storm Of A Lifetime ( Build Up To A Superstorm )

October 20, 2013
High Knob Massif ( Elevation 3300 feet )
Powell River Basin of Upper Tennessee River
Reflections Upon Autumn In Benges Basin
Photograph by Roddy Addington - © All Rights Reserved.

Nature senses changes at hand, with the wondrous migration of warblers accelerating during recent days!

October 18, 2013
Along the Tennessee Valley Divide
Yellow-rumped Warbler ( Dendroica coronata )
Photograph by Wayne Riner - © All Rights Reserved.

Wayne Riner Photograph Thoughts...
"At this time of the year, various birds migrate through the area for warmer winter homes.  This warbler stops by Long ridge to rest."

October 12, 2013
Karst Landscape of High Knob Landform
Mount Moriah Church Near Powell River
Eastern Red Cedar ( Juniperus virginiana )
Photograph by Harold L. Jerrell - © All Rights Reserved.

Illuminated by the final light of day, an old 
Red Cedar stands majestically upon the karst landscape of western Lee County.

October 12, 2013
Barn At Mount Moriah
Majestic Light  Accentuates Turbulent Sky
Photograph by Harold L. Jerrell - © All Rights Reserved.

Many majestic scenes have 
graced Autumn 2013.

Autumn 2013
The Beauty of Autumn Asters
Photograph by Harold L. Jerrell - © All Rights Reserved.

Autumn 2013
Mixed In Majestic Beauty - Native & Introduced
Photograph by Harold L. Jerrell - © All Rights Reserved.

The beautiful Cosmos has been 
introduced to Virginia.

September 2013
An Asteraceae Composite
Cosmos Flower ( Cosmos spp. )
Photograph by Harold L. Jerrell - © All Rights Reserved.

September 27, 2013
Cumberland Gap National Historical Park
Sunrise View From The Pinnacle Overlook
Photograph by Harold L. Jerrell - © All Rights Reserved.

September 27, 2013
Cumberland Gap National Historical Park
Countless Ridges Illuminated By Morning Sunrise
Photograph by Harold L. Jerrell - © All Rights Reserved.

Forever breathtaking, ripples of morning fog drain the Middlesboro Astrobleme Basin through historic Cumberland Gap.

September 27, 2013
Cumberland Gap National Historical Park
Waves Of Morning Fog Ripple Through Cumberland Gap
Photograph by Harold L. Jerrell - © All Rights Reserved.

September 28, 2013
Powell River of Upper Tennessee Basin
Autumn Sunset Over Silver Leaf
Photograph by Harold L. Jerrell - © All Rights Reserved.

October 18, 2013
A Cold Night On The Football Field
Friday Night Lights Above The City of Norton
Photograph by Roddy Addington - © All Rights Reserved.



First Accumulating Snow
Of Autumn 2013
October 23, 2013

Wise Plateau in Wise County, VA
Burst Of Afternoon Snow In Town of Wise
Photograph Courtesy of Talia Elliott & WCYB Archive

The first snowflakes of this season ended up being the first sticking snow for higher elevations of 
Wise County, Va., from the High Knob Massif north across portions of the Wise Plateau. 

October 23, 2013
NAM Model Analysis At 2:00 PM

While a passing upper air disturbance got snow started, it was mostly low-level orographic lifting on strong, gusty WNW winds that did much of the work amid an atmosphere largely dominated by subsidence ( sinking air ).

October 23, 2013
290 K Isentropic Surface
NAM Model Analysis At 2:00 PM

Observe the synoptic-scale subsidence of air ( above ) as cold air advection on WNW winds poured into the Appalachians, leeward of which sinking was further enhanced by downsloping into the Piedmont of the Carolina's and Virginia.

Vertical Cross-Section
NAM Model Analysis At 8:00 PM



Majesty Of The Seasons
Second Round of Snowfall
October 24-25, 2013

Upper Elevations of High Knob Massif
Gorgeous Autumn-Winter Contrast
Photograph by Becky Lagow - © All Rights Reserved.

Wise County photographer Becky Lagow captured "the shot" which characterized this first significant wintry blast of the season with a colorful Sugar Maple leaf lying upon pristine snow.

High Knob Massif
Southern Appalachian Northern Hardwoods
Sugar Maple Acer saccharum var. saccharum )
Photograph by Becky Lagow - © All Rights Reserved.

Becky also intelligently named and captured the nature of rime which coated upper elevations 
in the massif.

Upper Elevations of High Knob Massif
Beautiful Rime On High Knob
Photograph by Becky Lagow - © All Rights Reserved.

Rime has been made famous on this website by my friend and acclaimed, award winning photographer Roddy Addington.

October 2009
High Knob Dazzles In First Wintry Blast - Intro To RIME

( Amazing Rime Forest of March 2013 )
High Knob Massif RIME Forest of March 2013

The second round of snow developed during late afternoon and evening hours of October 24 with sticking snow levels dropping to 2000-2500 feet in the High Knob Massif - Tennessee Valley Divide corridor, including Norton-Wise and Sandy Ridge.

Elevation 3300 feet
High Chaparral of High Knob Massif
Snow Accumulaton at 5:42 AM October 25
Photograph by Darlene Fields - © All Rights Reserved.

The best sticking was above 3000 feet 
where a general 1" to 2" of snow fell.

A water content of 0.28" was reported by the Big Cherry Dam automated gauge, suggesting that locally more than 0.30" fell as snow in portions of the High Knob Massif.  A similar amount was reported from Whitetop Mountain ( suggesting that more snow fell than ever remained on this still unfrozen ground of mid Autumn, with 2-3" being local max amounts per water contents
and the temperature profile aloft ).

Elevation Around 2500 feet
East End of High Knob Massif
10:00 PM on October 24, 2013
Sticking Snow On Jaybird Branch of Guest River
Photograph Courtesy of Spike & WCYB Archive

While snow melted off the road, it was so cold up top on Eagle Knob of the High Knob Massif that snow and some rime held on the trees and ground throughout the afternoon.

( Temp 27 degrees )
Elevation 4189 feet
October 25, 2013 at 3:30 PM
Eagle Knob Communications Area of High Knob Massif
Image by Steve Blankenbecler - © All Rights Reserved.

The amount of snow at this latitude being held back by only a glancing fetch of Great Lake moisture as illustrated by airflow streamline analyses at 8:00 PM October 24 and 8:00 AM October 25.

( 8:00 PM Local Time October 24 )
NAM Model Analysis 00z October 25, 2013
Total Wind Streamlines At 950 MB and 850 MB

( 8:00 AM Local Time October 24 )
NAM Model Analysis 12z October 25, 2013
Total Wind Streamlines At 950 MB and 850 MB

Streamlines being a snapshot in time of the airflow at 8:00 AM and 8:00 PM and different from trajectories which follow flowing air over finite intervals of time.

From the Cumberlands to the Blue Ridge, this early fall of snow mixed with lingering autumn color to create a beautiful contrast across mid-upper elevations above 2500 feet.

October 25, 2013
Tennessee Valley Divide
Long Ridge of Sandy Ridge
Autumn Colors Mixed With Snow
Photograph by Genevie Riner - © All Rights Reserved.

Wayne & Genevie Riner had an 
interesting perspective...

October 25, 2013
Long Ridge of Tennessee Valley Divide
Beautiful Morning Along West Side of Divide 1
Photograph by Genevie Riner - © All Rights Reserved.

...on this first wintry period of 2013-14.

October 25, 2013
Lick Mountain of Tennessee Valley Divide
Beautiful Morning Along East Side of Divide 1
Photograph by Wayne Riner - © All Rights Reserved.

Genevie was on Long Ridge of Dickenson County,
along the west side of the Tennessee Valley Divide.

October 25, 2013
Long Ridge of Tennessee Valley Divide
Beautiful Morning Along West Side of Divide 2
Photograph by Genevie Riner - © All Rights Reserved.

Wayne was on Lick Mountain of Wythe County, 
along the east side of the Tennessee Valley Divide.

October 25, 2013
Lick Mountain of Tennessee Valley Divide
Beautiful Morning Along East Side of Divide 2
Photograph by Wayne Riner - © All Rights Reserved.

Wayne Riner Photograph Thoughts...
"The early snow has collected on the 
yellowed leaves of an American Chestnut."

October 25, 2013
Long Ridge of Tennessee Valley Divide
Beautiful Morning Along West Side of Divide 3
Photograph by Genevie Riner - © All Rights Reserved.

Both did an excellent job capturing 
this beautiful, but cold morning.

October 25, 2013
Long Ridge of Tennessee Valley Divide
Beautiful Morning Along West Side of Divide 4
Photograph by Genevie Riner - © All Rights Reserved.

Autumn is about change.

October 24, 2013
Between the Upper Tennessee & New River basins
Autumn Across Lick Mountain of Wythe County
Photograph by Wayne Riner - © All Rights Reserved.

October 24, 2013
The Morning Sunrise Above Matney Flats
Photograph by Wayne Riner - © All Rights Reserved.

October 27, 2013
Scenic Drive Along Long Ridge
October Colors Linger Amid The Thermal Belt
Photograph by Wayne Riner - © All Rights Reserved.

Wayne Riner Photograph Thoughts...
"Many areas have failed to produce brilliant fall colors; our favorite spot on Long Ridge did not disappoint."



Roaring Wind Event
of Halloween Night
( October 31 Into AM November 1 )

Why did it get so windy Halloween Night, with 
40-50+ MPH gusts common even before the potent cold front and its squall of wind arrived?

Several thousand American Electric Power ( AEP ) Customers lost electricity across southwestern Virginia and West Virginia by early overnight hours of November 1.

( 8:00 PM Local Time October 31, 2013 )
NAM Model Analysis - 00z November 1, 2013
Vertical Cross-Section Along 40N 91W 36N 81W
Graphic shows the connection between a potent
Upper-Level Jetstreak and Potent Low-Level Jet

After I worked out the derivation of the Isallobaric Wind component of the Ageostrophic Wind, and applied its application to the historic Black Hills blizzard of early October 2013, I was bullish on this being a high wind setting and was able to prepare a nice illustrative graphic almost as soon as the raw model data was generated by supercomputers at NMC ( see graphic above ).

The mathematical basis comes from Uccellini & Johnson ( 1979 ):
The Coupling of Upper & Lower Tropospheric Jet Streaks

A nice graphic of this is courtesy of the Atmospheric Science Department at the University of Illinois ( Urbana-Champaign ), and shows the final equation from Uccellini & Johnson ( 1979 ) which illustrates why it got so windy 
Halloween Night across this region.

From Uccellini & Johnson ( 1979 )
University Of Illinois At Urbana-Champaign

I derived the above equation beginning with the Momentum Equations ( equations of motion ) on Isentropic Surfaces, and the result clearly shows that an existing low-level jet will be enhanced and accelerated ( as well as coupled ) amid the exit region of an upper-level jetstreak.  So the strongest low-level jet winds in this particular setting ( to 90 MPH ) roared across the Bluegrass State and up into eastern portions of the Ohio Valley and Northeastern USA ( just as the ECMWF Model had predicted ).

Although a problem for western slopes of the Appalachians was downward momentum transfer amid the squall line ( which I am calling a WIND SQUALL since it had a history of minimal lightning-thunder ), outside of the already noted 40-50+ mph gusts
( which were even stronger above 3000 feet ).

( 8:00 PM Local Time October 31, 2013 )
NAM Model Analysis - 00z November 1, 2013
The Isallobaric Component made up the bulk of the
Ageostrophic Wind ( forcing cross-isobaric flow )

The gradient of surface pressure tendency, Term 1 in the above isallobaric equation, made up the bulk of the Ageostrophic Wind as displayed in vector form on the above graphic. 



Climate Statistics
For October 2013

( Lower Elevation of Russell Fork Basin )
Clintwood 1 W - Elevation 1560 feet
Average Daily MAX: 64.9 degrees
Average Daily MIN: 42.6 degrees
MEAN: 53.7 degrees
Highest Temperature: 80 degrees
Lowest Temperature: 20 degrees
Total Precipitation: 1.38"
Total Snowfall: Trace
2013 Precipitation: 41.53"

( Northern Base of High Knob Massif )
City of Norton - Elevation 2131 feet
Average Daily MAX: 63.0 degrees
Average Daily MIN: 39.6 degrees
MEAN: 51.3 degrees
Highest Temperature: 78 degrees
Lowest Temperature: 17 degrees
Total Precipitation: 1.63"
2013 Precipitation: 50.91"

( Along the Tennessee Valley Divide )
Nora 4 SSE - Elevation 2650 feet
Average Daily MAX: 61.6 degrees
Average Daily MIN: 46.7 degrees
MEAN: 54.2 degrees
Highest Temperature: 77 degrees
Lowest Temperature: 26 degrees
Total Precipitation: 1.11"
Total Snowfall: 0.3"
2013 Precipitation: 48.80"



Atmospheric Angular Momentum
Fluxes Forced By Opposing Mountain Torques

While the Appalachians have gotten into the flux act as well, its been the "big boys" on the block which have forced the most significant changes in Atmospheric Angular Momentum ( AAM ) between the Earth and Atmosphere during Autumn 2013.

( During Past 90 Days )
November 1, 2013 Summary
Mountain Torques By Region

Prolonged periods of positive & negative mountain torques have been forced by the Himalayas and Rockies, respectively, so far this autumn 
( with added contribution from the Andes & tropics ).

September 23 to October 31, 2013
( Correlated to Positive Himalayan Mountain Torque )
Asian 500 MB Vector Wind Composite Anomaly

The great Himalayas have, with little break, been exerting positive torque forces on the atmosphere since September 23.


Meanwhile, in North America, the Rockies pushed back against the mean westerlies with applied negative torque forces during the 
September 23-October 21 period.

While it is nearly certain that a new player is going to enter the wave forcing act via a hugely positive 500 MB Height Anomaly across the Northern Pacific in coming days, what remains unclear is if a downstream ripple in the flow field will amplify into the first significant snow of the season by November 12-14.

ECMWF Ensembles ( 12z Run On November 4 )
500 MB Height Anomalies At 12z November 14

The positive 500 MB anomaly centered near the Aleutians is in opposition to the mean climatological standing wave pattern which typically produces Wave 1 forcing, and would produce Wave 2 forcing instead. Meanwhile, subsequent runs of the ECMWF ensembles will be followed to see if what the operational run is showing ( below ) may show up in the flow field.

Operational Run of ECMWF ( 7:00 PM November 4 )
500 MB Height Anomalies At 00z November 14

Given the general teleconnection pattern this has 
a LOW chance of verifying, but will be a trend to follow in coming days.


( Updated November 10, 2013 )
Progressive Hit Of Arctic Air
Upslope Snow On NW-N Air Flow

While it is now certain that no big storm will strike this week, a shock blast of early season arctic air via a powerful 1047 MB High Pressure will generate a mid-winter day on November 12 as post-frontal snow and gusty winds create bone chilling conditions ( i.e., after the front passes ).

With dewpoints in 10s and 20s in advance of this system it is a no brainer, as even Meteorology 101 dictates, that wet bulbing will quickly chill temps adding to the cooling effect as described by the Thermodynamic Energy Equation.

Thermodynamic Energy Eq. in Isobaric Coordinates

( The rate of change of temperature with respect to time
+ the horizontal advection terms ) - the Vertical Motion Effect
= the Diabatic Heating/Cooling.

This equation can be rewritten and rearranged, but basically in this case all terms add up to cooling along the upslope side of the Appalachians.

The total rate of change of temperature 
following the motion equals:

Horizontal Cold Air Advection
+
Cooling With Upsloping NW-N winds
+
Cooling Due to Evaporation
( Wet Bulbing Amid Initially Dry Air )

In other words, locations along and north of the High Knob Massif will experience enhanced cooling effects as all terms add up to aid temperature drops ( the same type of setting being applicable to locations along and N-NW of the Tennessee Valley Divide, Clinch Mountain, and the Mount Rogers-Whitetop mass ).

Snow easily stuck, especially at higher elevations, in October so it is again a no brainer that it will stick in November ( and is nothing atypical for now ).

Hazardous driving conditions are expected during morning hours of November 12 ( despite the lack of any advisories for such on the higher, VA side of the stateline ).

12z November 10, 2013
ECMWF 500 MB Height Anomalies

The teleconnections leading up to this initial blast were mostly all out of phase for a big Appalachian snowstorm ( thus the low odds ).

A changing teleconnection pattern, however, is being suggested by all major operational models such that next week ( November 17-23 ) will be one to watch across the USA.

12z November 20, 2013
ECMWF 500 MB Height Anomalies

Model trends toward -AO & -NAO along with +PNA signals at least the potential for a headline making storm in the USA ( severe weather and heavy rains on its warm side and another blizzard in its cold sector ).  Stay tuned.

This section is under construction.  Check back for updates.

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