Thursday, August 1, 2013

Recap Of July 2013 - Huge Rainfall Gradients


Water Elevation 2734 feet
Jefferson National Forest & VDGIF
Bark Camp Lake of High Knob Massif
Gorgeous Sunshine Follows A Chilly July Morning
Photograph by Roddy Addington - © All Rights Reserved.


The High Knob Landform was amid excessive rainfall during the summers of 2010, 2011, and 2012 ( High Knob Massif & Cumberland Gap NHP areas ).

( Excessive Rainfall of August 2010 )


July 2012 - Doppler Estimated Rainfall


While rainfall has been locally excessive during Summer 2013, clearly the corridor of widespread excessive rains became focused along the eastern slopes of the Appalachians and western Piedmont during July ( and southern Cumberland Plateau ).

July 2013 - Doppler Estimated Rainfall

Many places had rainfall totals that were 10.00" to 15.00"+ above established normals for July, with near record to all-time record amounts.

The only previous July with more rainfall 
in many upslope locations was July 1916.

July 2013 - Doppler Estimated Rainfall

Observe on these graphics how the heaviest rains have been focused along the Blue Ridge escarpment, which plunges off to
the western Piedmont, with more inland areas to the west of this escarpment along the eastern slopes of the Blue Ridge having much less rainfall ( which fits climatology ).



July 2013 Rainfall Totals
Southern Appalachians

North Carolina

( 1981-2010 Climate Period )
North Carolina Observed Climate Normals

Elevation 5280 feet
*Grandfather Mountain: 23.91"
+17.93" above the July Normal

Note that the 17.93" surplus during July 2013 was only 0.04"
below the average rainfall for the entire summer season that was recorded on average during the 1981-2010 observation period.

Landis Taylor also reported the following additional
July rainfall totals from Grandfather Mountain:

Grandfather Entrance Gate: 29.24"
( Courtesy of Entrance Gate Employees )

Grandfather Fudge Shop: 28.91"
( Courtesy of The Naturalist Staff )

*All-time Record For July shattering the old
record of 11.92" established during July 1989.

Elevation 3840 feet
Highlands: 23.50"
+17.16" above 1981-2010 July Normal

The wettest July on record in Highlands
was in 1916 with 35.49" of rainfall

Elevation 3080 feet
Lake Toxaway: 23.00" ( M )
42.19" of rainfall since June 1 ( M )

Elevation 6240 feet
Mount Mitchell: 22.15"
+16.53" above 1981-2010 July Normal

Elevation 3770 feet
Banner Elk: 20.29"
+15.16" above 1981-2010 July Normal

The wettest July on record in Banner Elk
was in 1916 with 28.06" of rainfall

Elevation 3360 feet
Boone 1 SE: 19.70"
+14.97" above 1981-2010 July Normal

Elevation 5053 feet
Beech Mountain: 18.69"
+13.26" above 1981-2010 July Normal

Elevation 2165 feet
Asheville: 13.69"
+10.36" above 1981-2010 July Normal
( Only 0.06" shy of all-time wettest month of any year )

RECORD EVENT REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC

...A NEW MONTHLY RAINFALL RECORD
FOR JULY SET AT ASHEVILLE NC...

RAINFALL FOR THE MONTH OF JULY WAS 13.69 INCHES AT THE ASHEVILLE AIRPORT. THIS SURPASSES THE PREVIOUS RECORD RAINFALL FOR THE MONTH OF JULY FOR THE ASHEVILLE AREA OF 11.71 INCHES SET IN 1905.  CLIMATOLOGICAL RECORDS FOR THE ASHEVILLE AREA DATE BACK TO 1869.



Tennessee

( 1981-2010 Climate Period )
Tennessee Observed Climate Normals

Elevation 6400 feet
Mount LeConte: 15.28"
+8.47" above 1981-2010 July Normal

Elevation 1500 feet
Tri-Cities: 7.11"
+2.42" above 1981-2010 July Normal



Virginia

( 1981-2010 Climate Period )
Virginia Observed Climate Normals

Elevation 2360 feet
Galax WTP: 15.28"
+11.04" above 1981-2010 July Normal for area

Elevation 2225 feet
Meadows Of Dan 5 SW: 14.91"
+9.56" above 1981-2010 July Normal

Elevation 1175 feet
Roanoke: 12.73"
+8.69" above 1981-2010 July Normal

Elevation 571 feet
Danville: 11.50"
+6.91" above 1981-2010 July Normal

Elevation 4000 feet
Grayson Highlands State Park: 11.22"
( Davis Vantage Pro2 Automated Weather Station )

Elevation 2926 feet
Konnarock: 7.99"
( USGS Automated Gauge )

Elevation 2132 feet
Blacksburg: 7.78"
+3.52" above 1981-2010 July Normal

Elevation 2172 feet
Marion: 6.95"
( TVA Rain Gauge )

Elevation 1733 feet
Saltville 1 N: 6.17"
+1.14" above 1981-2010 July Normal

Elevation 3068 feet
Burkes Garden: 6.03"
+1.55" above 1981-2010 July Normal


NATIONAL WEATHER SERVICE BLACKSBURG VA
925 AM EDT THU AUG 1 2013

...RAINFALL TOTALS AND RECORDS SET IN JULY 2013...

ROANOKE VIRGINIA RECEIVED 12.73 INCHES OF RAIN...WHICH MADE JULY 2013 THE WETTEST JULY EVER RECORDED. THE OLD JULY RAINFALL RECORD WAS 10.09 INCHES FROM 1989. IT WAS ALSO THE SECOND WETTEST MONTH OF ALL TIME IN RECORDED HISTORY. THE CURRENT ALL TIME WETTEST MONTH RECORD IS 16.71 INCHES FROM AUGUST 1940. RECORDS FOR ROANOKE DATE BACK TO 1912.

DANVILLE VIRGINIA RECEIVED 11.50 INCHES OF RAIN...WHICH MADE JULY 2013 THE WETTEST JULY EVER RECORDED. THE OLD JULY RAINFALL RECORD WAS 8.81 INCHES FROM 1965. IT WAS ALSO THE FOURTH WETTEST MONTH OF ALL TIME IN RECORDED HISTORY. THE CURRENT ALL TIME WETTEST MONTH RECORD IS 14.64 INCHES FROM SEPTEMBER 1996. RECORDS FOR DANVILLE DATE BACK TO 1948.

BLACKSBURG VIRGINIA RECEIVED 7.78 INCHES OF RAIN...WHICH MADE JULY 2013 THE THIRD WETTEST JULY EVER RECORDED. THE CURRENT JULY RAINFALL RECORD IS 9.35 INCHES FROM 1992. RECORDS FOR BLACKSBURG DATE BACK TO 1952.

BLUEFIELD WEST VIRGINIA RECEIVED JUST 4.12 INCHES OF RAIN...WHICH WAS WELL SHORT OF THE CURRENT JULY RAINFALL RECORD OF 10.24 INCHES FROM 1980. BLUEFIELD ACTUALLY FINISHED BARELY BELOW THE 1981-2010 NORMAL FOR RAINFALL IN JULY...WHICH IS 4.17 INCHES. RECORDS FOR BLUEFIELD DATE BACK TO 1959.

FINALLY...LYNCHBURG VIRGINIA RECEIVED ONLY 3.41 INCHES OF RAIN...WHICH WAS FAR BEHIND THE CURRENT JULY RAINFALL RECORD OF 10.30 INCHES FROM 1984. LYNCHBURG FINISHED BELOW THE 1981-2010 NORMAL FOR RAINFALL IN JULY...WHICH IS 4.36 INCHES. RECORDS FOR LYNCHBURG DATE BACK TO 1893.

July 2013
Doppler Estimated Departure From Normal

July 2013 rain totals were somewhat above and below longer-term averages along the western slopes of the Appalachians and western portion of the Great Valley, as generally suggested by Doppler estimated departures, with 5.00" to 9.00" being common in the High Knob Massif - Tennessee Valley Divide and Clinch River Valley.

Elevation 2650 feet
Nora 4 SSE: 8.44"
( Long Ridge of Sandy Ridge )

Elevation 2290 feet
Little Stone Mountain Gap: 7.97"
( 3.0 miles WSW Norton - VDOT Station )

Elevation 2267 feet
Coeburn Filter Plant: 7.83"
( 3.5 air miles NE of Downtown )

Fort Blackmore IFLOWS: 7.83"
( 2.8 air miles SE of High Knob Massif )

Fort Blackmore 4 SE: 7.28"
( CoCoRaHS Station )

Elevation 2342 feet
City of Norton WP: 6.51"
+1.02" above 1983-2012 July Average

Elevation 2360 feet
Appalachia Lake WP: 6.16"
+0.46" above 1985-2012 July Average

Elevation 1912 feet
Lebanon: 5.66"
+1.09" above estimated 1981-2010 July Normal

Elevation 1170 feet
Grundy: 5.38"
+0.18" above 1981-2010 July Normal

Elevation 1910 feet
Richlands: 5.32"
+1.00" above estimated 1981-2010 Normal

Elevation 1560 feet
Clintwood 1 W: 4.05"
-0.70" below 1981-2010 July Normal



July 2013 Rainfall
Central Appalachians

West Virginia

( 1981-2010 Climate Period )
West Virginia Observed Climate Normals

Elevation 824 feet
Huntington: 7.90"
+3.35" above 1981-2010 July Normal

Elevation 910 feet
Charleston: 7.37"
+2.43" above 1981-2010 July Normal

Elevation 4850 feet
Snowshoe Mountain: 6.31"
+1.35" above 1981-2010 July Normal

Elevation 3815 feet
Davis 3 SE: 5.03"
-0.53" below 1981-2010 July Normal
( Canaan Mountain )

Elevation 2514 feet
Beckley: 4.62"
-0.41" below 1981-2010 July Normal

Elevation 1979 feet
Elkins: 4.32"
-1.04" below 1981-2010 July Normal

Elevation 2300 feet
Lewisburg 3 N: 4.15"
+0.13" above 1981-2010 July Normal

Elevation 2870 feet
Bluefield: 4.12"
-0.36" below 1981-2010 July Normal

Elevation 534 feet
Martinsburg: 3.14"
-0.53" below 1981-2010 July Normal

It is interesting to note that for Summer 2013 so far, from June 1 to July 31, rainfall totals have regionally varied from 42.19"+ at Lake Toxaway, NC., to 7.14" in Martinsburg, WV.

July 10, 2013
Along The Tennessee Valley Divide
Sunshine Through Falling Rain & Black Clouds
Photograph by Wayne Riner - © All Rights Reserved.

Wayne Riner Photograph Thoughts...
"The sounds of distant thunder marked the start of the usual afternoon and evening thunderstorms.  Here, the sun is partly hidden by a thin veil of rain."


Climate Statistics
For July 2013

( Lower Elevations of Russell Fork Basin )
Clintwood 1 W - Elevation 1560 feet
Average Daily MAX: 80.3 degrees
Average Daily MIN: 60.5 degrees
July MEAN: 70.4 degrees
Highest Temperature: 87 degrees
Lowest Temperature: 51 degrees
July Rainfall: 4.05"
Rainfall Since June 1: 11.71"
2013 Precipitation: 32.67"

( Northern Base of High Knob Massif )
City of Norton - Elevation 2141 feet
Average Daily MAX: 78.9 degrees
Average Daily MIN: 57.5 degrees
July MEAN: 68.2 degrees
Highest Temperature: 86 degrees
Lowest Temperature: 47 degrees
July Rainfall: 6.51"
Rainfall Since June 1: 15.08"
2013 Precipitation: 42.65"

( Along the Tennessee Valley Divide )
Nora 4 SSE - Elevation 2650 feet
Average Daily MAX: 77.5 degrees
Average Daily MIN: 62.3 degrees
July MEAN: 69.9 degrees
Highest Temperature: 84 degrees
Lowest Temperature: 53 degrees
July Rainfall: 8.44"
Rainfall Since June 1: 15.27"
2013 Precipitation: 38.86"

July featured near to below average temperatures with average daily maximums that only reached around 70 degrees at highest elevations amid the High Knob Massif.  This coupled with average nightly mins in mid 50s to lower 60s ( coolest in high valleys ) generated July MEANS 
in the mid-upper 60s.

A notable feature has been the lack of high temperatures with only 7 days this year climbing above 80 degrees at the 2650 foot elevation of Nora 4 SSE on Long Ridge of Sandy Ridge 
( 84 degrees being the 2013 max to date ).

No days have reached 80 degrees at highest elevations in the High Knob Massif ( ** ).

**This refers to calibrated thermometers that are
never in direct sunlight ( i.e., official NWS readings ).

The compensating factor, of course, has been many high dewpoint days such that feels-like conditions have made many days feel hotter.



Consistent Wetness
City of Norton
( January 1-August 1 )

The past 3 years up to this point in time have generated consistent wetness in the High Knob Massif area, as nicely exemplified 
by the City of Norton.

*City of Norton WP
Total Precipitation
January 1-August 1

2011
42.99"

2012
42.37"

2013
42.98"

1983-2012 Average
36.63" ( M )

*Totals up to 9:00 AM on August 1
( includes all rain falling through July 31 at midnight ).

( M ) - Missing data during the 1983-1998 period in snowfall.

Yes it seems ironic, as 2013 grabs the headlines with excessive rains that have places like the 
Tri-Cities, Tn., Blacksburg, Danville, and Roanoke in Virginia already near their annual precipitation totals, and rarely only a little behind the City of Norton, that its just HO-HUM for Norton where 2013 marks the third year with the same surplus. 

The change across Virginia this year has been radical as generalized by a comparison of the USA Drought Monitor for the Commonwealth during the 2011-2013 period.

Virginia Drought Monitor On August 2, 2011

Virginia Drought Monitor On July 31, 2012

Virginia Drought Monitor On July 30, 2013

No drought anywhere across Virginia at the end of July 2013 verses 50-75%+ of the state with at least abnormal dryness during the previous two years.

While the Old Dominion of Virginia has been north of the truly extreme wetness of late spring-summer 2013, as already highlighted by North Carolina records, its been wet enough that wetter areas along the southern Blue Ridge ( e.g., Meadows of Dan, Galax, Mount Rogers & Whitetop Mountain ) are now running close to the wettest areas in the High Knob Landform ( e.g., Big Cherry Lake Basin & Cumberland Gap NHP area ) for the year to date.


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