July 11, 2010 - High Knob Massif
Pipevine Swallowtail ( Battus philenor )
Photograph by Roddy Addington - © All Rights Reserved.
The stunning Pipevine Swallowtail Butterfly is part of mid-summer majesty in the High Knob Landform. A common species observed during summer in the mountains ( given you take a moment to simply be still and observe the great natural world around you! ).
[ Dutchman's Pipe ( Aristolochia macrophylla ) tends to be their host plant with the various species of resident Milkweeds ( Asclepias spp. ) serving as sources of nectar ].
[ Dutchman's Pipe ( Aristolochia macrophylla ) tends to be their host plant with the various species of resident Milkweeds ( Asclepias spp. ) serving as sources of nectar ].
Pipevine Swallowtail In Motion - Identification Marks
Photograph by Roddy Addington - © All Rights Reserved.
Identified by a distinct curl of seven orange spots on its hindwing, the Pipevine Swallowtail is merely one of more than 1,000 species of butterflies and moths gracing this truly diverse landscape of these ancient mountains!
( Males have few to no white spots on their forewings )
Male Pipevine Swallowtail ( Battus philenor )
Photograph by Roddy Addington - © All Rights Reserved.
Other swallowtail butterflies in this area include:
Zebra Swallowtail ( Eurytides marcellus )
Photograph by Alan Cressler - © All Rights Reserved.
Giant Swallowtail
( Papilio cresphontes )
Eastern Tiger Swallowtail ( Papilio glaucus )
Photograph by Alan Cressler - © All Rights Reserved.
Black Swallowtail
( Papilio polyxenes )
Black Swallowtail ( Papilio polyxenes ) Caterpillar
Photograph by Alan Cressler - © All Rights Reserved.
Spicebush Swallowtail ( Papilio troilus )
Photograph by Alan Cressler - © All Rights Reserved.
Spicebush Swallowtail ( Papilio troilus ) Caterpillar
Photograph by Alan Cressler - © All Rights Reserved.
Appalachian Tiger Swallowtail
( Pterourus appalachiensis )
Giant Swallowtail
( Papilio cresphontes )
Eastern Tiger Swallowtail ( Papilio glaucus )
Photograph by Alan Cressler - © All Rights Reserved.
Black Swallowtail
( Papilio polyxenes )
Black Swallowtail ( Papilio polyxenes ) Caterpillar
Photograph by Alan Cressler - © All Rights Reserved.
Spicebush Swallowtail ( Papilio troilus )
Photograph by Alan Cressler - © All Rights Reserved.
[ Smaller Summer Azure ( Celastrina neglecta ) Butterflies are also present in the above scene ].
Spicebush Swallowtail ( Papilio troilus ) Caterpillar
Photograph by Alan Cressler - © All Rights Reserved.
Appalachian Tiger Swallowtail
( Pterourus appalachiensis )
Before butterflies turn into the truly gorgeous creatures we most often see, many of their larval forms are simply incredible ( as highligted above )!
Consider Roddy's absolutely beautiful, gentle looking Pipevine Swallowtail, which does not look so tame wrapped in its larval armory!!
Consider Roddy's absolutely beautiful, gentle looking Pipevine Swallowtail, which does not look so tame wrapped in its larval armory!!
Pipevine Swallowtail ( Battus philenor ) Caterpillar
Photograph by Alan Cressler - © All Rights Reserved.
Wow, what a transformation!
Wow, what a transformation!
July 11, 2010 - High Knob Massif
Great Spangled Fritillary ( Speyeria atlantis )
Photograph by Roddy Addington - © All Rights Reserved.
Great Spangled Fritillary is one of numerous beautiful fritillaries to grace this most wondrous mountain landscape, adding color to its amazing palette of hues which extend from subterranean depths into the heavens above!
Meadow Fritillary
( Boloria bellona )
Silver-bordered Fritillary
( Boloria selene )
Variegated Fritillary
( Euptoieta claudia )
Aphrodite Fritillary
( Speyeria aphrodite )
Diana Fritillary ( Speyeria diana )
Photograph by Roddy Addington - © All Rights Reserved.
Regal Fritillary
( Speyeria idalia )
Another incredible creature currently working summer flowers is often mistaken for our resident Ruby-throated Hummingbird ( Archilochus colubris ).
July 11, 2010 - High Knob Massif
Hummingbird Clearwing Moth ( Hemaris thysbe )
Photograph by Roddy Addington - © All Rights Reserved.
The Hummingbird Clearwing is actually a form of sphinx moth of the family Lepidoptera.
At certain angles it is possible to see right through the centers of their amazing wings!
At certain angles it is possible to see right through the centers of their amazing wings!
Hummingbird Clearwing Moth ( Hemaris thysbe )
Photograph by Roddy Addington - © All Rights Reserved.
In addition to their incredibly long tongues, clear center wings, and awesome tail flaps, these little flying machines are a potpourri of colorations.
Hummingbird Clearwing Moth - High Knob Massif
Photograph by Roddy Addington - © All Rights Reserved.
Weather Conditions
for July 1-15, 2010
Looking to South Fork Gorge of High Knob Massif
Multi-layered Clouds - AM of July 14, 2010
Photograph by Roddy Addington - © All Rights Reserved.
With all the color in this section, I thought it good to illustrate the pure beauty of mid-summer in the High Knob Landform with a wonderful black & white photograph by Roddy Addington.
[ Color is great for certain, but there is still something special about black & white photographs, especially given an awesome scene as viewed from the floor of Powell Valley in Wise County, Va., during early morning light ( with different orographic processes working to generate multiple cloud layers ) ].
Climate Statistics for July 1-15, 2010
Clintwood 1 W - Elevation 1560 feet
Average Max: 83.0 degrees
Average Min: 57.5 degrees
Mean: 70.2 degrees
Highest Temperature: 90 degrees
Lowest Temperature: 45 degrees
Days at or above 90 degrees in 2010: 2
Rainfall: 1.25"
2010 Precipitation: 26.25"
City of Norton - Elevation 2141 feet
Average Max: 82.2 degrees
Average Min: 55.0 degrees
Mean: 68.6 degrees
Highest Temperature: 89 degrees
Lowest Temperature: 44 degrees
Days at or above 90 degrees in 2010: 0
Rainfall: 1.14"
2010 Precipitation: 30.19"
In the High Knob highcountry, July 1-15 temp means varied from 70s by day to 50s by night, with mean July temperatures actually being lower than June ( as also observed in Clintwood & Norton ).
A general 1.00" to 3.00" of rain fell during the first half of the month across the massif ( heaviest between Big Cherry Basin & Bark Camp Lake of Little Stony Basin in northern Scott County, Virginia ).
A general 1.00" to 3.00" of rain fell during the first half of the month across the massif ( heaviest between Big Cherry Basin & Bark Camp Lake of Little Stony Basin in northern Scott County, Virginia ).
[ The lower mean July temperatures being due to cool nights, with lower-middle 50s on average within the cooler mountain basins of mid-upper elevations in the massif area ].
Colorful Version of Multi-layered Clouds - July 14
Photograph by Roddy Addington - © All Rights Reserved.
Rainfall during the first half of July was below average, with nary a drop during the first 9 days of the month. Wetness finally returning in the past week, with local 3.00" to 4.00"+ amounts in Lee County and the southwest end of the High Knob Landform ( especially across Cumberland Gap NHP ).
Regional Climate Statistics
for July 1-15, 2010
Jackson, Ky., NWSFO - Elevation 1365 feet
Average Max: 84.5 degrees
Average Min: 65.6 degrees
Mean: 75.0 degrees
Highest Temperature: 91 degrees
Lowest Temperature: 57 degrees
Days at or above 90 degrees in 2010: 5
Rainfall: 1.51"
2010 Precipitation: 27.45"
London, Kentucky - Elevation 1211 feet
Average Max: 87.2 degrees
Average Min: 64.9 degrees
Mean: 76.0 degrees
Highest Temperature: 95 degrees
Lowest Temperature: 55 degrees
Days at or above 90 degrees in 2010: 12
Rainfall: 1.70"
2010 Precipitation: 23.81"
Buckhorn Lake SP, Kentucky - Elevation 936 feet
Average Max: 87.9 degrees
Average Min: 63.0 degrees
Mean: 75.4 degrees
Highest Temperature: 95 degrees
Lowest Temperature: 50 degrees
Days at or above 90 degrees in 2010: 26
Rainfall: 1.92"
2010 Precipitation: 23.01"
Buckhorn Lake SP, Kentucky - Elevation 936 feet
Average Max: 87.9 degrees
Average Min: 63.0 degrees
Mean: 75.4 degrees
Highest Temperature: 95 degrees
Lowest Temperature: 50 degrees
Days at or above 90 degrees in 2010: 26
Rainfall: 1.92"
2010 Precipitation: 23.01"
Tri-Cities, Tennessee - Elevation 1525 feet
Average Max: 90.1 degrees
Average Min: 62.5 degrees
Mean: 76.3 degrees
Highest Temperature: 97 degrees
Lowest Temperature: 58 degrees
Days at or above 90 degrees in 2010: 22
Rainfall: 0.88"
2010 Precipitation: 16.54"
Knoxville, Tennessee - Elevation 981 feet
Average Max: 92.1 degrees
Average Min: 69.8 degrees
Mean: 81.0 degrees
Highest Temperature: 99 degrees
Lowest Temperature: 63 degrees
Days at or above 90 degrees in 2010: 33
Rainfall: 3.33"
2010 Precipitation: 23.18"
Richmond, Va., ( State Capitol ) - Elevation 167 feet
Average Max: 93.3 degrees
Average Min: 68.2 degrees
Mean: 80.8 degrees
Highest Temperature: 104 degrees
Lowest Temperature: 56 degrees
Days at or above 90 degrees in 2010: 37
Rainfall: 0.60"
2010 Precipitation: 18.22"
The regional trend has been for northwest to southeast gradients in weather conditions, with hotter and drier conditions within the Great Valley and locations east of the Appalachians verses areas toward the northwest ( with exception of lower elevations amid the Kentucky foothills, this has also been exemplified by a notable upward spike in the number of 90 degree days in 2010 ).
Majestic Morning In The HKL - July 14, 2010
Photograph by Roddy Addington - © All Rights Reserved.
With respect to topographic variations, the same conditions highlighted on this website that forced earlier autumn colorations and later spring emergence in higher elevations of the High Knob Landform remain at work during summer ( they are just not as visible to untrained eye, since everything is now green outside of any drought stricken locations in the region ).
[ Reference the following sections on my website:
September Generates Wetness And Colorations
http://www.highknoblandform.com/2009/10/september-generates-wetness-and.html
High Knob Landform - Glorious Color Climax
http://www.highknoblandform.com/2009/10/high-knob-massif-reaches-glorious-color.html
Colors Peak In Lower Elevations of Cumberlands
http://www.highknoblandform.com/2009/10/lower-elevations-peak-in-breaks.html
HKL Spring Differences: Elevation + Latitude
http://www.highknoblandform.com/2010/05/spring-differences-with-elevation.html ].
Harvestman or Granddaddy Long-legs ( Leiobunum sp. )
on a Poke Milkweed ( Asclepias exaltata ) - High Knob Massif
Photograph by Roddy Addington - © All Rights Reserved.
[ Reference the following sections on my website:
September Generates Wetness And Colorations
http://www.highknoblandform.com/2009/10/september-generates-wetness-and.html
High Knob Landform - Glorious Color Climax
http://www.highknoblandform.com/2009/10/high-knob-massif-reaches-glorious-color.html
Colors Peak In Lower Elevations of Cumberlands
http://www.highknoblandform.com/2009/10/lower-elevations-peak-in-breaks.html
HKL Spring Differences: Elevation + Latitude
http://www.highknoblandform.com/2010/05/spring-differences-with-elevation.html ].
Radio Tower Elevation 3779 feet
Morris Butte of High Knob Massif - July 14, 2010
Photograph by Roddy Addington - © All Rights Reserved.
During July 1-15, for example, average nightly lows in the 50s were locally common outside of well exposed middle elevation ridges and plateaus of the thermal belt ( e.g., Nora 4 SSE & LNP ).
Minimums early in July dipped into the upper 30s to middle 40s within the High Knob Massif area, in rather dramatic contrast to the Great Valley of east Tennessee where July mins have only been in the upper 50s to lower 60s ( note July min of only 63 degrees in Knoxville, Tn., is 8 degrees warmer than the average nightly low in Norton for the entire July 1-15 period ).
Implications Of Climatic Differences
( Part of the BIG Picture )
( Part of the BIG Picture )
High Knob Massif - July 11, 2010
Canada Lily ( Lilium canadense )
Photograph by Roddy Addington - © All Rights Reserved.
Cooler mean temperatures allows northern species of flora & fauna, such as this magnificent Canada Lily found by my friend Roddy Addington in the High Knob Massif, to live within higher elevations of the High Knob Landform.
Canada Lily
( Lilium canadense var. canadense )
Canada Lily Variation ( Darker Phase )
( Lilium canadense var. editorum )
High Knob Massif
Illuminated by Afternoon Light - July 11, 2010
Photograph by Roddy Addington - © All Rights Reserved.
To be more precise, a darker phase or variation in this species has been recognized as noted above.
High Knob Massif - July 11, 2010
Turk's Cap Lily ( Lilium superbum )
Photograph by Roddy Addington - © All Rights Reserved.
Although Turk's Cap Lilies have a widespread range across Virginia, from the coastal plain to the mountains, those living within the highlands tend to reside in upper elevations.
Beauty of Turk's Cap Lily - High Knob Massif
Photograph by Roddy Addington - © All Rights Reserved.
These gorgeous highcountry lilies are merely the tip of a great iceberg of differences forced by climate changes directly related to terrain variations, which span all realms of the natural sciences.
Looking Up South Fork Gorge - High Knob Massif
Photograph by Roddy Addington - © All Rights Reserved.
Everything presented on this website during the past 11 months has only just started to scratch the surface of these natural realms, the collective array of which defines what the High Knob Landform is.
High Knob Massif - July 9, 2010
Rugged Karst Landscape of High Knob Landform
Photograph by Roddy Addington - © All Rights Reserved.
The High Knob Landform ( HKL ) is:
A great continuous mountain landform
consisting of:
consisting of:
1 ). a remnant massif of highcountry ( High Knob Massif )
2 ). a northwestern mountain flank ( * )
3 ). a southeastern mountain flank
4 ). an eroded calcareous core that separates
the mountain flanks and narrows by headward erosion,
to the northeast, into the inverted V-shaped
the mountain flanks and narrows by headward erosion,
to the northeast, into the inverted V-shaped
Powell Valley ( adjacent to the High Knob peak ) .
*Contains Cumberland Gap National Historical Park and other magnificent natural wonders.
The above being the most basic definition for an extremely large and richly diverse Appalachian landform of the awesome Upper Tennessee & Upper Cumberland river basins ( a mountain landform so large that the biggest portion of the Clinch Mountain range, from Brumley Mountain to Round Mountain, could easily fit inside of its eroded calcareous core between The Cedars NAP and Cove Lake State Park in Tennessee ).
[ Reference the following section for the Name & Purpose of this website:
March 2010: Second Week - Spring Prelude!
http://www.highknoblandform.com/2010/03/march-2010-second-week-spring-prelude.html ].
High Knob Massif - July 11, 2010
White Bergamot ( Monarda clinopodia ) Spotted Variety
Photograph by Roddy Addington - © All Rights Reserved.
[ Reference the following section for the Name & Purpose of this website:
March 2010: Second Week - Spring Prelude!
http://www.highknoblandform.com/2010/03/march-2010-second-week-spring-prelude.html ].
High Knob Massif - July 9, 2010
Karstic Rock Outcrop - Edge of Mountain Meadow
Photograph by Roddy Addington - © All Rights Reserved.
NOTE: The following section of the website began to document severe flash flooding in Pike County, Ky., into the evening of July 17, 2010. New updates were then added on the dates given.
Weather Update - July 18, 2010
Killer Flash Flooding Strikes
Pike County, Kentucky
JKL Doppler Rainfall Estimate - 12:01 AM July 18, 2010
Image Courtesy of Plymouth State University
[ Flash flooding developed as thunderstorms trained, and back built, along a stalled boundary of high energy air ( called a theta-e gradient ) situated over Pike County, Ky., with a downstream drift or propagation into portions of Buchanan and northern Tazewell counties of southwestern Virginia ].
Given the volatile nature of this mid-July atmosphere, I wanted to highlight the sudden, violent, and tragic flash flooding that struck Pike County, Ky., during the evening hours of July 17.
Although the Doppler radar rainfall estimate above has some hail contamination, making it read too high, several rain gauges reported 4.00" to 5.00"+ of rainfall ( mostly fell between 5 p.m. and 10 p.m. July 17 ).
Two individuals lost their lives as homes, cars, and many other structures were literally washed away down creeks!
[ The Pike County Sheriff's Office initially reported 3 deaths. Thankfully, that was downgraded to 2 and all of the missing have reportedly been accounted for. Some good news in the wake of this tragedy ].
WSAZ NewsChannel 3 Team Coverage
of Pike County, Ky., Flash Flood
Video Courtesy of WSAZ-TV in Huntington, West Virginia
This occurred just 35 to 40 air miles north to northeast of the High Knob Landform, and is part of a series of torrential downpours that have struck localized corridors during the past several days.
Until this air mass changes it signals, like a Red Flag, that other local flash flooding events will be possible across the region.
Updated - July 24, 2010
Another severe flash flood event unfolded into early hours of July 21, north of Pike County, Ky., as thunderstorms trained along and just south of the Ohio River.
WSAZ NewsChannel 3 Coverage of
Carter County, Ky., Flash Flooding
Video Courtesy of WSAZ-TV in Huntington, West Virginia
[ The body of a 72-year old Carter County, Ky., woman was not found until July 24, after severe flash flooding had swept her mobile home off its foundation. Flood waters carried her 6 miles downstream ].
JKL Doppler Rainfall Estimate - July 21, 2010
Image Courtesy of Plymouth State University
Important Follow Up Note...
HEAT had increased as of July 24, but the air mass had NOT changed. As another front stalls during the week of July 25-31, the threat for more hit-miss flash flood events will be renewed!
[ Folks living along creeks and rivers, and in flood prone locales, should remain alert for rapid water rises should heavy rains develop over or upstream of their location ].
Updated - July 26, 2010
Yet Another Flash Flood Death
JKL Doppler Rainfall Estimate - 8 PM July 25, 2010
Image Courtesy of Plymouth State University
Amazing Report
Courtesy of WSAZ-TV in Huntington, West Virginia
UPDATE 7/26/10 @ 6:45 p.m. by WSAZ-TV
Chris Ryan died despite a heroic rescue attempt.
We talked with family and friends - and the second man in - who was lucky to get out alive.
Into our second week of intense storms, West Virginia has now sadly joined eastern Kentucky and southern Ohio on the fatal flood list.
The scenarios are the same -- more rain in less time and swifter currents than ever seen before.
This time, a dad was trying to make sure his daughter got home safely. In the process, he was swept away.
Kelly Ryan says her husband Chris was clearing debris from the flood-swollen creek and road at their Thurmond Street home -- so a daughter on a play date could get home safely. But then she says the Sunday evening rain hit harder -- the water came up high and fast -- maybe 6 feet -- and Chris went in.
Kelly told us that Chris was able to get his face up and say he was OK – that his daughter was in there and so was he.
Kelly and her daughter made it out safely. Chris was still heading downstream.
Kelly says next-door neighbor Paul Bentley ran past 20 bystanders and jumped into the rushing water. He says he was trying to keep Chris from getting sucked into a culvert drain pipe.
"I grabbed his hand but he went under, and I went in the drain pipe," Paul Bentley said. "It took four to five guys to pull me out. I was in there ten minutes. It got me from here on my stomach on down; I wish there was more I could have done."
Searchers found Chris Ryan’s body more than a mile down stream -- on the other side of Danville in the Little Coal River.
Kelly Ryan says her husband was a good man a good dad; he would help anybody with anything.
Chris Ryan was a 41-year-old disabled coal miner. He leaves behind his wife Kelly of 17 years, as well as three daughters.
Bentley, the brave man who attempted the rescue, was treated and released with a number of injuries. He said he jumped in because he knew Chris Ryan would do the same for him."
WSAZ NewsChannel 3 Coverage of
Boone County, Wv., Flash Flooding
Boone County, Wv., Flash Flooding
Video Courtesy of WSAZ-TV in Huntington, West Virginia
July 2010 has become a month of incredible regional extremes, from a continuing series of killer flash floods to blazing heat and drought.
The bottom line...this is a dangerous, repetitive pattern that must be respected ( updated 2 AM on July 27, 2010 ).
Updated - July 24, 2010 at Midnight
Why Mountain Heatwaves Are Rare
( Mountain Valleys vs. Lowlands )
Powell Valley of High Knob Massif
Typical Mountain Valley Fog - AM of July 21, 2010
Photograph by Roddy Addington - © All Rights Reserved.
Heat has historically been the silent but deadly killer, with folks in the mountains and lowlands alike needing to be more cautious on days which are "hot" relative to what is "normal" for them!
[ Although varying with National Weather Service coverage areas, a Heat Advisory is generally issued when the combination of temperature and humidity will make it feel like 100 to 115 degrees for up to 3 hours during the day, and/or there is expected to be at least 2 consecutive nights with minimum temperatures above 80 degrees. An Excessive Heat Warning is issued for even more extreme conditions, posing a grave danger to all homeothermic organisms ].
One of the seemingly more simple but fascinating aspects of climatology, which has held my interest since a kid, is the way mountain valleys cool off at night throughout the year.
It is this cooling at night combined with the naturally lower temperatures occurring at higher elevations by day, which collectively make true heatwaves rare within the mountains.
[ Oh, it is a wave of HEAT for mountain residents since it is HOT compared to what they are used too and is often a sticky, miserable feeling type of heat in "jungle-like" locations with high humidity levels.
In comparison to lower elevations and to urban areas, however, it is not as severe ( and there is relief at night ) ].
In comparison to lower elevations and to urban areas, however, it is not as severe ( and there is relief at night ) ].
Looking to South Fork Gorge of High Knob Massif
Multi-layered Clouds - AM of July 21, 2010
Photograph by Roddy Addington - © All Rights Reserved.
[ While looking similar to photographs taken on July 14, the above scene captured by Roddy illustrates how common such multi-layered clouds are during summer in this landform, as air at various different levels cools to its dewpoint nearly every night ].
I have been officially observing weather conditions for the National Weather Service now for more than 21 years, and recording temps for most of the past 35 years. In all that time I have never had a night remain above 70 degrees, and I do not even live in a higher mountain valley ( above 2000 feet ).
News Flash - No Longer True
Check out the section on July 2011 heat:
Example - Midnight on July 24, 2010
Local Temperatures ( degrees Fahrenheit )
City of Norton: 69 degrees
MECC in Big Stone Gap: 70 degrees
Clintwood 1 W: 71 degrees
L.F. Addington MS in Wise: 71 degrees
Lonesome Pine Airport in Wise: 72 degrees
In the High Knob highcountry, midnight temperatures in cooler basins, above 2400 feet elevation, were generally in middle to upper 60s ( dewpoints were in the lower 60s on Eagle Knob to provide a source for cool air drainage into these higher mountain basins ).
In contrast to these already good temperature drops, readings across much of the region were still hot ( outside of the mountains ).
Regional Temperatues at Midnight
July 24, 2010
Virginia
Tazewell: 70 degrees
Lebanon: 73 degrees
Blacksburg: 77 degrees
Hillsville: 79 degrees
Roanoke: 80 degrees
Lynchburg: 81 degrees
Martinsville: 81 degrees
Danville: 82 degrees
Staunton: 82 degrees
Charlottesville: 84 degrees
Farmville: 86 degrees
Richmond: 86 degrees
Fredericksburg: 88 degrees
Stafford: 88 degrees
West Point: 88 degrees
Williamsburg: 88 degrees
Hanover: 89 degrees
Quantico: 89 degrees
Fort Belvoir: 90 degrees
Washington National: 91 degrees
Tennessee
Mountain City: 69 degrees
Tri-Cities: 77 degrees
Crossville: 77 degrees
Oak Ridge: 79 degrees
Knoxville: 81 degrees
Knoxville: 81 degrees
Chattanooga: 83 degrees
Kentucky
Middlesboro: 73 degrees
London: 75 degrees
Hazard: 77 degrees
Jackson: 79 degrees
Lexington: 79 degrees
West Virginia
Elkins: 72 degrees
Beckley: 74 degrees
Bluefield: 77 degrees
Charleston: 77 degrees
Huntington: 79 degrees
Parkersburg: 81 degrees
Morgantown: 82 degrees
Locally cooler mountain locations are likely present in the above states, as exemplified by the many elevated basins in the High Knob Massif, to illustrate how cool air drainage can temper even the more intense periods of summer heat.
[ Note that exposed middle elevation ridges, not subjected to cool air drainage or naturally cooler air in upper elevations, tend to occasionally have summer nights which can remain above 70 degrees ( but they rarely rise above 90 degrees by day ) ].
[ Note that exposed middle elevation ridges, not subjected to cool air drainage or naturally cooler air in upper elevations, tend to occasionally have summer nights which can remain above 70 degrees ( but they rarely rise above 90 degrees by day ) ].