Friday, August 1, 2014

Wet & Cool July 2014 - Climate Statistics


Severe Thunderstorm Outbreak Of July 27, 2014
Vivid Lightning Above The Powell River Basin
Photograph by Harold L. Jerrell - © All Rights Reserved.


Climate Statistics
For July 2014

( Lower Elevations of Russell Fork Basin )
Clintwood 1 W - Elevation 1560 feet
Average Daily MAX: 77.6 degrees
Average Daily MIN: 57.1 degrees
July MEAN: 67.4 degrees
Highest Temperature: 85 degrees
Lowest Temperature: 46 degrees
July Rainfall: 6.15"
Rain Since June 1: 12.23"
Rain Since May 1: 17.01"
2014 Precipitation: 29.73"
( +0.39" above 1981-2010 Average )

( Northern Base of High Knob Massif )
City of Norton - Elevation 2141 feet
Average Daily MAX: 76.6 degrees
Average Daily MIN: 54.1 degrees
July MEAN: 65.4 degrees
Highest Temperature: 85 degrees
Lowest Temperature: 43 degrees
July Rainfall: 6.63"
Rain Since June 1: 10.71"
Rain Since May 1: 15.76"
2014 Precipitation: 31.33"
( -5.17" below 1983-2013 Average )

( Along the Tennessee Valley Divide )
Nora 4 SSE - Elevation 2650 feet
Average Daily MAX: 75.3 degrees
Average Daily MIN: 61.0 degrees
July MEAN: 68.2 degrees
Highest Temperature: 84 degrees
Lowest Temperature: 53 degrees
July Rainfall: 5.17"
Rain Since June 1: 10.40"
Rain Since May 1: 14.36"
2014 Precipitation: 26.11"

July 2014 was the coolest experienced since 2009 which featured an especially chilly July with mean temperatures 1 to 2 degrees Fahrenheit lower than this July ( Summer 2009 was cool & wet ).

Wet Summer Across The High Knob Landform In 2009

The July MAX temperature only reached 73 degrees 
at the summit level of the High Knob Massif during 
July 2009 verses 76 degrees in July 2014.

July 2014 built upon wetness of June with rainfall totals of 6.00" to 10.00" being widespread from the High Knob Massif area to Cumberland Gap National Historical Park.

Elevation 2267 feet
( Along the Tennessee Valley Divide )
3.5 air miles NE of Downtown Coeburn
Coeburn Filter Plant
July Rainfall: 6.67"
Rain Since June 1: 12.85"
Rain Since May 1: 15.59"
2014 Precipitation: 29.15"

Elevation 2360 feet
1.6 air miles ESE of Downtown Appalachia
( Little Stone Mountain of High Knob Massif )
Appalachia Lake Water Plant
July Rainfall: 6.27"
Rain Since June 1: 11.92"
Rain Since May 1: 16.09"
2014 Precipitation: 31.48" 

Elevation 2289 feet
2.9 air miles SW of Downtown Norton
( Little Stone Mountain of High Knob Massif )
Little Stone Mountain VDOT
July Rainfall: 7.04"
Rain Since June 1: 12.96"
*Rain Since May 1: 17.12"

Elevation 3239 feet
Benges Basin of High Knob Massif
Lower Norton Reservoir
July Rainfall: 6.67"
Rain Since June 1: 14.61"
*Rain Since May 1: 19.72"

Upper Tennessee River Basin
Watershed of The City of Norton
Lower Norton Reservoir of High Knob Massif
Water Elevation 3239 feet Above Sea Level

The beautiful Lower Norton Reservoir in Benges Basin has not been photographed as much as the Upper Reservoir which rests adjacent to 
State Route 619.

Upper Norton Reservoir is 5.2 air miles NNE
of Big Cherry Lake Dam and 6.7 air miles
WNW of Bark Camp Lake Dam.

October 4, 2014
Water Elevation 3318 feet
Upper Norton Reservoir In Autumn 2013
Photograph by Roddy Addington - © All Rights Reserved.

Elevation 3318 feet
Benges Basin of High Knob Massif
Upper Norton Reservoir
July Rainfall: 8.33"
Rain Since June 1: 15.95"
*Rain Since May 1: 21.83"

*One missing rainfall event during May
( 0.72" measured at Norton Water Plant ).

January 22, 2014
Frozen Upper Norton Reservoir
Photograph by Bill Harris - © All Rights Reserved.

( Wet 66-Day Period )
Upper Norton Reservoir
Days With Measurable Rainfall
May 27 to July 31, 2014

Totals Ending Daily Around 6-8 AM

05-28-2014  1.07"
05-29-2013  2.53"
05-30-2014  0.35"

06-04-2014  0.08"
06-05-2014  0.75"

06-10-2014  0.42"
06-11-2014  0.03"
06-12-2014  0.92"
06-13-2014  1.18"
06-14-2014  0.73"

06-17-2014  0.16"

06-20-2014  2.53"
06-21-2014  0.31"
06-22-2014  0.01"

06-25-2014  0.02"
06-26-2014  0.41"

06-29-2014  0.05"
06-30-2014  0.02"

07-02-2014  0.08"

07-09-2014  0.85"
07-10-2014  0.88"

07-15-2014  1.64"
07-16-2014  0.42"
07-17-2014  0.01"
07-18-2014  0.02"
07-19-2014  0.85"
07-20-2014  0.95"
07-21-2014  0.01"

07-23-2014  0.01"
07-24-2014  0.01"
07-25-2014  1.69"

07-27-2014  0.01"
07-28-2014  0.88"
07-29-2014  0.01"

07-31-2014  0.01"

Total: 19.90"

A total of 18.05" reported during this
period at the Lower Norton Reservoir.

*Doppler radar estimated 0.60" to 1.00" during the one missing event on May 21-22, and implied rain amounts at the Lower-Upper Reservoirs in Benges Basin were greater than the 0.72" measured at the Norton Water Plant.  This suggested around 22.83" fell at Upper Norton Reservoir during the entire May 1-July 31 period.

Although hard to believe, and to illustrate this amazing contrast, the May 27-July 31 period produced only 5.24" of rain at the official measuring site in Blacksburg of the New River Valley ( 12.81-14.66" less than Benges Basin ).


Approximately 10.56" of July rain fell in the Robinson Knob community, some 4.9 air miles ESE of Upper Norton Reservoir, making over 19.00" since June 1 and 24.00"+ since May 1 
amid headwaters of Bark Camp Lake.

September 26, 2010
Water Elevation 2734 feet
Upper Tennessee River Basin
Little Stony Creek Watershed
Bark Camp Lake of High Knob Massif
Photograph by Roddy Addington - © All Rights Reserved.

A general 35.00" to 45.00" of precipitation fell across upper elevations of the High Knob Massif during the January-July 2014 period 
( up to 5.00" below average ).

The wettest 40.00" to 45.00" corridor included at least upper portions of all basins of the 5 mountain top lakes which rest upon the core of this massif.

Majesty In Big Cherry Lake Basin & South Fork Gorge


Moisture Gradient
Across Southwestern Virginia

An eastward shift in the main area of dryness has been observed across southwestern Virginia.  This has been the case since at least late May, but has not been fully reflected by official indicators until the most recent late July updates.



Updated Site Totals
January 1 to July 31, 2014

Galax WTP
July Rainfall: 2.29"
Rain Since June 1: 3.74"
Rain Since May 1: 8.13"
2014 Precipitation: 17.58"

Bluefield ( WV )
July Rainfall: 2.95"
Rain Since June 1: 6.55"
Rain Since May 1: 9.35"
2014 Precipitation: 18.22"

Wytheville 1 S
July Rainfall: 1.81"
Rain Since June 1: 5.33"
Rain Since May 1: 8.26"
2014 Precipitation: 18.77"

Blacksburg
July Rainfall: 1.92"
Rain Since June 1: 4.99"
Rain Since May 1: 7.67"
2014 Precipitation: 19.82"

Tri-Cities ( TN )
July Rainfall: 5.25"
Rain Since June 1: 8.83"
Rain Since May 1: 11.03"
2014 Precipitation: 20.83"

Burkes Garden
July Rainfall: 3.76"
Rain Since June 1: 7.45"
Rain Since May 1: 10.09"
2014 Precipitation: 20.90"

Richlands
July Rainfall: 6.23"
Rain Since June 1: 8.92"
Rain Since May 1: 12.06"
2014 Precipitation: 21.42"

Saltville 1 N
July Rainfall: 4.76"
Rain Since June 1: 8.93"
Rain Since May 1: 12.68"
2014 Precipitation: 23.29"

Lebanon
July Rainfall: 3.82"
Rain Since June 1: 7.70"
Rain Since May 1: 11.44"
2014 Precipitation: 23.39"



Where's The HEAT
Cool Summer of 2014

The cool & wet weather pattern of Summer 2014 has many asking "Where's The Heat," with MAX summer temps to date having reached only middle 80s at elevations of Norton, Wise, and Long Ridge of Sandy Ridge ( 76 degrees being the max at the High Knob Massif summit level ).

This was also true during 2013 when the Summer MAX
in Wise officially reached 85 degrees on June 12.

Welcome To Autumn 2013 - Recap Of Summer 2013


MAX Annual Temperatures
Wise 3 E and Wise 1 SE
*( MAX Temp & Date of Occurrence )

Wise 3 E NWS Cooperative
Elevation 2549 feet

85  6-12-2013
95  6-29-2012
86  7-28-2011
90  7-25-2010
85  8-10-2009
87  7-21-2008
92  8-24-2007
88  8-02-2006
88  7-25-2005
88  8-04-2004
88  8-26-2003
89  8-03-2002
86  7-24-2001
87  8-07-2000
91  7-31-1999
90  9-14-1998
89  8-16-1997
90  5-19-1996
93  7-15-1995
92  6-19-1994
90  9-01-1993


Wise 1 SE NWS Cooperative
Elevation 2560 feet

87  7-13-1992
86  9-16-1991
89  9-07-1990
86  7-11-1989
94  8-18-1988
91  8-22-1987
88  6-22-1986
88  6-10-1985
86  6-15-1984
92  8-22-1983
85  8-05-1982
87  7-27-1981
92  7-16-1980
87  8-08-1979
89  6-27-1978
89  7-17-1977
89  7-24-1976
89  9-05-1975
85  7-18-1974
88  9-02-1973
86  7-23-1972
86  8-10-1971
87  7-29-1970
88  7-06-1969
89  8-22-1968
85  6-18-1967
92  7-14-1966
89  8-18-1965
88  6-22-1964
90  8-03-1963
88  8-21-1962
86  7-21-1961
86  9-06-1960
88  8-24-1959
86  7-28-1958
89  8-13-1957
88  8-06-1956
91  8-04-1955

Average Annual MAX: 88.4 degrees
( 59 years from 1955 to 2013 )

*While some years may have had more than 1 day at the reported MAX, these were the highest temperatures observed during each year ( missing data was noted during 1984 and 1986 ).
All temperatures in degrees Fahrenheit.

Data courtesy of Roy L. Wells, Jr., NWS Cooperative Observer, and the National Climatic Data Center.


A review of the past 59 years finds that only 16 years, or 27 percent, reached 90 degrees or higher at the official National Weather Service ( NWS ) Cooperative Stations in the town of Wise.

The longest stretch with no 90 degree readings was observed from 1967-1979 when 13 years passed with no temperatures above 85 to 89 degrees.

The longest recent stretch without 90 degree temperatures in Wise was the 7 year period from 2000 to 2006 ( max 89 degrees August 3, 2002 ).

Annual maximums have occurred as early in the year as May 19 and as late as September 16.

When summer is wet it often forces MAX temperatures for the year to be skewed either early and/or late in the warm season amid the mountains.

Higher elevations in the High Knob Massif, and along the Tennessee Valley Divide, have lower annual maximums than Wise ( especially above 3000 feet and along northern exposed slopes ).

Some northern slope locations between 2000 and 3000 feet in the High Knob Massif also tend to have lower maximums than Wise due to exposure and more daytime cloudiness & rainfall.

A survey finds that the average annual max on Eagle Knob of the High Knob Massif was 9 degrees lower than observed in Wise, which implies that 
79 degrees is typical for a Summer MAX.


Supercell Thunderstorms
Of July 27, 2014

Afternoon of July 27, 2014
Large Hail Pounds Lee County, Virginia
Photograph by Rodney Parsons - © All Rights Reserved.

Violent supercell thunderstorms erupted July 27 
in advance of an unseasonably cool air mass.

July 27, 2014 at 8:00 AM
Lonesome Pine Airport In Wise
NAM Model Initialization Skew-T

Development of spring-like upper air dynamics 
( cold air & wind shear ) over top a mid-summer air mass ( high moisture contents ) set the stage for formation of large hail and local tornadoes in the strongest supercells.

July 27, 2014 at 8:00 PM
Lonesome Pine Airport In Wise
NAM Model Initialization Skew-T

The probability of having a Supercell jumped from 45% at
8:00 AM to 80% by 8:00 PM as wind shear and vertical
lapse rates increased into afternoon hours of July 27.

July 27, 2014 at 4:43 PM
CAM Elevation 2600 feet
Looking Toward High Knob Massif
University Of Virginia's College At Wise
Courtesy Of Computer Science-Mathematics Department

An ominous sky developed as a violent supercell, with a history of large hail and wind damage in southeastern Kentucky, crossed Lee County of 
the High Knob Landform and approached the southwestern end of the cloud capped 
High Knob Massif.

July 27, 2014 at 4:44 PM
Looking Toward High Knob Massif
University Of Virginia's College At Wise
Courtesy Of Computer Science-Mathematics Department

July 27, 2014 at 4:47 PM
Looking Toward High Knob Massif
University Of Virginia's College At Wise
Courtesy Of Computer Science-Mathematics Department

July 27, 2014 at 4:53 PM
Looking Toward High Knob Massif
University Of Virginia's College At Wise
Courtesy Of Computer Science-Mathematics Department

July 27, 2014 at 4:58 PM
Looking Toward High Knob Massif
University Of Virginia's College At Wise
Courtesy Of Computer Science-Mathematics Department

July 27, 2014 at 5:01 PM
Looking Toward High Knob Massif
University Of Virginia's College At Wise
Courtesy Of Computer Science-Mathematics Department

July 27, 2014 at 5:05 PM
Looking Toward High Knob Massif
University Of Virginia's College At Wise
Courtesy Of Computer Science-Mathematics Department

This particular supercell by-passed the highest terrain of the Cumberland Mountains, the core passing southwest of main crestlines of Big Black Mountain and between the High Knob Massif and Cumberland Gap National Historical Park, which did not bode well for downstream locations into northeastern Tennessee in this case ( # ).

#Past climatology shows that supercell storm structure tends to change when crossing the High Knob Massif - Black Mountain corridor, whether for good or bad, to alter impacts upon downstream locations.  These changes being forced by orographics and associated upslope/downslope - convergence/divergence & deformations.


NASA Visible Images
Explosion of Supercell Thunderstorms

NASA Visible Image At 12:15 PM on July 27

NASA Visible Image At 12:30 PM on July 27

NASA Visible Image At 1:00 PM on July 27

NASA Visible Image At 1:15 PM on July 27

NASA Visible Image At 1:45 PM on July 27

NASA Visible Image At 2:15 PM on July 27

NASA Visible Image At 2:30 PM on July 27

NASA Visible Image At 2:45 PM on July 27

NASA Visible Image At 3:15 PM on July 27

NASA Visible Image At 3:45 PM on July 27

NASA Visible Image At 4:00 PM on July 27

Counties Overlay With Temperatures
NASA Visible Image At 4:00 PM on July 27

NASA Visible Image At 4:15 PM on July 27

NASA Visible Image At 4:30 PM on July 27

NASA Visible Image At 4:45 PM on July 27

NASA Visible Image At 5:15 PM on July 27

Counties Overlay With Temperatures
NASA Visible Image At 5:15 PM on July 27


Doppler Radar Images
Basic Base Reflectivities & Warnings

JKL Doppler & Warnings At 4:30 PM July 27

JKL Doppler & Warnings At 4:36 PM July 27

JKL Doppler & Warnings At 4:41 PM July 27

JKL Doppler & Warnings At 4:46 PM July 27

JKL Doppler & Warnings At 4:57 PM July 27

JKL Doppler & Warnings At 5:03 PM July 27

JKL Doppler & Warnings At 5:13 PM July 27

JKL Doppler & Warnings At 5:19 PM July 27

JKL Doppler & Warnings At 5:24 PM July 27

JKL Doppler & Warnings At 5:29 PM July 27

JKL Doppler & Warnings At 5:35 PM July 27

JKL Doppler & Warnings At 5:46 PM July 27

JKL Doppler & Warnings At 5:51 PM July 27


Summary Of Storm Reports
JKL & MRX NWSFO

Jackson, KY NWS Forecast Office

Morristown, TN NWS Forecast Office


Autumn-like Chill
In Wake Of Thunderstorms
( 3rd Major Cool Push of July 2014 )

July 27, 2014 at 8:45 PM
Looking Toward High Knob Massif
University Of Virginia's College At Wise
Courtesy Of Computer Science-Mathematics Department

From muggy, mid-summer air into 
an early autumn-like setting.

July 28, 2014 at 2:37 PM
Looking Toward High Knob Massif
University Of Virginia's College At Wise
Courtesy Of Computer Science-Mathematics Department

Although analogous to the Independence Day cool spell, with low dewpoint air and MIN temperatures that dipped into upper 30s to lower 40s amid mid-upper elevation mountain valleys of the High Knob Massif area into morning hours of July 30, this push of cool air possessed an interesting twist!

Comparison Images

July 2, 2014 at 2:26 PM
Looking Toward High Knob Massif
University Of Virginia's College At Wise
Courtesy Of Computer Science-Mathematics Department

In looking at these two images, prior to the coolest mountain valley MINS ( July 4-5 & July 30-31 ), there is an added element to this latest NW Flow.

July 29, 2014 at 12:24 PM
Looking Toward High Knob Massif
University Of Virginia's College At Wise
Courtesy Of Computer Science-Mathematics Department

Canadian Smoke from Forest Fires!


Running a 5-day backward air flow trajectory into Wise revealed air flow coming right out of a region where many forest fires have been raging.

Analysis Of Smoke Plume - July 29, 2014

This section is under construction.  Check back for updates.