Posted by Devin Greaney ACROSS TENNESSEE on Monday, March 15, 2010 ·
Tennessee Weather: The skies over Tennessee fall into History
Clouds and sunset show off
Lookout Mountain from this
postcard from 1909 or 1910
Tennessee weather has its averages, extremes and the just plain weird.
A visitor walked into the MEMPHIS WEEKLY LEDGER office with a jar of snakes. It was January 15, 1877 and the visitor claimed these snakes fell from the sky. Several others corroborated the story. He said the rain was a drizzle, the drizzle turned into a torrent and when the torrent subsided, residents of the two-block area on Vance between Orleans and Lauderdale found thousands of dark brown snakes slithering across the ground.
Most weather is not that dramatic. But seldom does weather stay exactly to averages. The difference between weather and climate is simply summed up in an old saying – “Climate is what you expect, weather is what you get.” Let’s start out with climate.
The Southeast Regional Climate Center at the University of North Carolina has compiled historic averages of temperature, rainfall and snowfall of all of Tennessee’s weather stations. Some stations have been monitoring weather since the mid nineteenth century but in order to get an average climatologist usually look at a thirty-year time span. Looking at the averages paints a picture of climate in Tennessee.
Most of Tennessee stays close to the same high temperature in July. Historic data has records the average high temperatures for July in the high 80’s or low 90’s, with Memphis and Savannah averaging 92 degrees. They are the warm spots of the state. But the average July high temperature at most weather reporting stations stays within about 5 degrees of each other, so moving from Memphis to Knoxville to escape the heat only means an average 4 degree break. However, thanks to the mountains in the east, we do have some summer havens.
Mountain City, which is the farthest northeastern weather station, averages an 82 degree high temperature in July. . The stations at Crossville, Monterey, Jamestown and Monteagle, also mountain towns, average just 2 degrees warmer than Mountain City. Mountains do interesting things with weather, as you will soon see.
As those mountain people in the Northeast are enjoying their temperate summers, they pay for it in the winter while West Tennessee flatlanders enjoy relative warmth. Mountain City, Tazewell and Oneida average January low temperature of 22 to 24 degrees as does Waverly in Middle Tennessee. December 30, 1917 Mountain City residents must have been begging for those 22 degree temperatures when Tennessee hit its record low temperature of minus 32 degrees.
Ice flows damaged these river boats on the
Mississippi near Memphis in January, 1918.
Courtesy Memphis/Shelby County Public Library
Our urban environments can affect temperature for several reasons which work together to create what climatologists call “the urban heat island effect.” Davis Nolan, chief meteorologist with WKRN-TV in Nashville has been observing the weather in the state’s largest city since 1981. “In SUMMER I estimate the temperature over the concrete in Nashville can range some 4 to 8 degrees above the official thermometer at the airport taken over grass,” he says. “The same official temperature is one to 2 degrees warmer than surrounding towns (also taken over a grass field but with less concrete.) This is less pronounced over a winter day but I estimate the temperature is still two to three degrees warmer over concrete on a sunny day.”
David Gaffen, David Holtz and Terry Getz studied weather data in the Smokey Mountains in An Evaluation of Temperature Variations around the Great Smoky Mountains National Park and their Associated Synoptic Weather Patterns. The researchers looked at 10 years of data from five National Park Weather stations – park headquarters, Cades Cove, Oconaluftee (North Carolina), Mount Le Conte and Newfound Gap, plus Knoxville’s McGhee- Tyson Airport.
Knoxville generally stayed a bit warmer than the park, because of the urban heat island effect and its lower elevation. Park headquarters is located in a valley, and had temperatures averaging a difference between 12 and 15 degrees Fahrenheit warmer than Mount Le Conte and between 7 and 10 degrees warmer than Newfound Gap.
Rainfall in West and Middle Tennessee is similar throughout the area. But in the mountains a phenomenon known as orographic lifting forces warm, moist air rapidly aloft causing it to cool. Since cool air cannot hold as much water vapor as warm air, the water vapor condenses into clouds and those clouds produce rain and snow. Ronnie Millsap’s song “Smokey Mountain Rain” was both a country hit of 1980 AND climatologically correct as some of the state’s wettest areas are in the mountains. 57 inches of precipitation are the average in Athens, Copperhills, Lawrenceburg and Sewanee and 58 inches is average in Rockwood. The wettest town in the state is Monteagle averaging 61.8 inches of precipitation. But there is a place in Tennessee that makes even Monteagle look arid. The National Park Service reports an average of 85 inches of precipitation at Clingman’s Dome, the state’s highest point. That is greater than the average yearly amount of rainfall in Seattle, Washington and Portland, Oregon combined.
Dr Henri Grissino-Mayer, a geography professor at the University of Tennessee-Knoxville, has studied the climate of the Smokies. “Any type of mountain chain that runs north south is going to significantly affect climate regimes on the west side of the chain and the east of the chain and in the mountains themselves. In the northern hemisphere all of our weather moves from west to east,” he says. “The climate on the eastern side of the mountains is different on the western side,” he says “That is why the Smokey Mountains have so much rain. All mountain ranges are effective rain traps”
Out west moisture moves from the Pacific, is forced up the mountains and on the other side of the mountains the weather is drier. Think of those deserts past the Sierra and Cascade Mountains. “The Appalachians do not create a rain shadow east like we see in the Sierra Nevada and the Rocky Mountains because we have quite a bit of moisture coming out of the Gulf and the lower latitudes of the Atlantic are on the wet side of subtropical high pressure that dominates the Mid Atlantic called the Bermuda High. Well still have quite a bit of pressure driven moisture east of the mountains. In the Southeastern US we have several moisture drivers.”
Thanks to the cooler temperatures, parts of the Smokies are like pieces of the north removed- the far north. “Because of the moisture regime and the unique temperature regime we have vegetation exactly like you find in New England. The northern hardwood forest found in Tennessee is the species you would normally associate with New England. We also have truly remarkable spruce-fur forest. These are only found in the highest elevations and in the highest latitudes. In Canada they are called boreal forests. That to me is fascinating we can see a boreal forest in Tennessee.”
This tornado was photographed
near Paris March 11, 1942. Courtesy
National Oceanic Atmospheric Administration
Climate stays, for the most part, the same. Weather is where the drama is found. And when one thinks of drama one thinks of tornadoes.
Most associate tornadoes with the Midwest area known as “Tornado Alley” because they have seen dramatic photos and video of the twisters plowing through fields of Texas, Oklahoma and Kansas. And it is true those areas are often hit, but they also make for better pictures with flat lands and few trees. Here in “Dixie Alley” tornadoes are more likely to form at night with Tennessee leading the state in nighttime twisters. Dixie Alley has more population density than West Texas, trees hide the approaching danger and high humidity mean more of them are concealed in rainstorms.
The deadliest day in Tennessee for tornadoes was March 21 and 22, 1952 when from 6 PM to 1 AM sixty- seven Tennesseans were killed, mostly in West Tennessee. The counties with the most deaths were Chester (23), Dyer (16), Henderson (11), Fayette (7), Hardeman (4) and Hickman (3). Gibson and Carroll counties also had fatalities.
May 10, 1933 a twister traveled northeast from Livingston to Byrdstown killing thirty-five, thirty-three of whom were in the tiny town of Beatty Swamps, six miles north of Livingston. Today maps do not show a community of Beatty Swamps, only a road and cemetery bearing that name. And the largest tornado outbreak in US history struck several states April 3, 1974 killing thirty-three in Tennessee.
More recently a West Tennessee outbreak February 5, 2008 killed thirty-two Tennesseans. Jackson was hit and fifty-one were injured at Union University. Over the last fifteen years it seems Jackson has had worse tornado luck than cities of “Tornado Alley” as part of “Dixie Alley.” January 17, 1999 six were killed when a tornado hit south and central Jackson. The city erected Unity Park downtown to commemorate the tragedy two years later. May 4, 2003 downtown Jackson and the memorial, was hit by a tornado. Two were killed in downtown Jackson and nine in Denmark about twelve miles away.
A tornado also went through the heart of Nashville April 19, 1998, later tearing up the grounds of Andrew Jackson’s estate. There is a myth tornadoes do not hit large cities. Tennesseans know better.
Weather has played an important part in Tennessee’s history. An early spring storm near Camden March 5, 1963 brought down a small plane forever silencing the voices of country music stars Patsy Cline, Cowboy Copas, Hawkshaw Hawkins and Cline’s manager and pilot, Randy Hughes.
A snowstorm in Memphis changed its history. March 21, 1968 was a rainy Spring day with a forecast of cold weather later, but forecasters expected the rain to have retreated by the time cold air arrived in Memphis. Retired Memphis TV meteorologist Dave Brown was working at WHBQ radio which at the time was near the University of Memphis. “We got a call in the afternoon from a woman saying it was snowing silver dollar-sized flakes in Frayser (a neighborhood on the northwest side of Memphis). We dismissed it but then looked outside and that is what we saw.” At 4:22 PM, the Weather Bureau (which became the National Weather Service in 1971) at the airport reported snowfall, but Brown said no one was expecting it to stick to the warm ground. This was the first day of spring and just two days earlier Memphis had a high of 79 degrees. “But it just kept falling,” he remembers. The airport closed after the last flight out and snow was still coming down. By the time the snow ended the next day at 1:30 PM, 16.1 inches had fallen. The snow left just as quickly as it fell. “Within thirty-six to forty-eight hours there was no trace of the snow,” Brown says. March 25 the temperature reached 62 degrees.
The storm made history not as Memphis’ largest snowfall- another March storm in 1892 was larger. This snow made history because it canceled the arrival of Martin Luther King to Memphis. He had planned to march with striking garbage workers on March 22. King instead arrived March 28. Convicted assassin James Earl Ray arrived in Memphis April 3 and King was killed the next day.
Other historical events:
In what was called “The Storm of the Century” on March 13 and 14, 1993 snow and snow fall records fell in the eastern part of the nation when a powerful low pressure system mixed moisture and cold to cover about two-thirds of the state. The snowiest spot in the lower 48 that day was Mount LeConte with 60 inches. Chattanooga had 20 inches. Knoxville’s daily newspapers were not published on March 13th. But all of West Tennessee plus the Middle Tennessee stations of Savannah and Dickson only received trace amounts of snow.
Eighty-three people died in Memphis July, 1980 in a heat wave that gripped most of Middle America. That is the number are those who had listed on the death certificates heat exhaustion, heat stroke or systemic hyperthermia, according to a study for American Geriatrics. However, the same study reported 90 more people died that month from cardiovascular emergencies than the previous July, indicating 83 was probably a conservative number. Most of the dead were poor and elderly without adequate air conditioning and kept their windows shut for fear of crime. Memphis hit its all-time record temperature that month at 108 degrees- a record that still stands. As for the hottest recorded temperature in the state, that was at Perryville near Mousetail Landing State Park which recorded 113 degrees twice in 1930.
August, 1989 was a wet month for Memphis. When the month was winding down, intense heat, high humidity and a very slow breeze covered the city with haze. On August 30, the high hit 92 degrees with relative humidity anywhere from 60 to 90 percent. Those factors combined created conditions that hastened the decay of anything organic, increased mold and fungus growth, trapped in pollutants which combined to cause residents to complain the entire city smelled like fish.
Also in Memphis July 22, 2003 morning commuters thought they were seeing a tornado. Extreme winds estimated by the National Weather Service at up to 100 miles per hour raced through Memphis doing $500 million in damage and leaving some residents without power for up to two weeks. “Hurricane Elvis” was the name locals gave it, though it was neither a tornado nor a hurricane. It was called a “derecho” or straight line winds. Centuries-old trees were pulled out of the ground like weeds, walls of buildings and power lines were blown down and one person was killed during the event. Six others had deaths relating to the storm such as asphyxiation from gas powered generators.
On I-75 over the Hiwassee River near Calhoun, dense fog December 11, 1990 caused two tractor trailers to collide. Due to the low visibility, other vehicles began colliding creating a chain reaction traffic accident. Ninety-nine vehicles were involved resulting in twelve deaths and forty-two injuries.
Details are a bit sketchy, such as the date and circumstances of how this happened, but in an article on the National Weather Services’ website Mark Rose, meteorologist for the National Weather Service’s Old Hickory office quotes SYMON’S MONTHLY METEOROLOGICAL MAGAZINE from September, 1869. The magazine said on a hot summer day five miles from Ashland City in Cheatham County “sort of a whirlwind” witnessed by some two hundred people was pulling in leaves and branches and setting them on fire. The whirlwind described as “a fiery cylinder” eventually singed horse’s manes, burnt hay and eventually farmer Ed Sharp’s home. As it passed over a river, a column of steam lifted into the air about one-half mile high, according to witnesses.
April 10, 1994 a lightning strike killed one person and injured eighteen during an ultimate Frisbee match in Antioch.
A few Tennessee names are associated with weather and climate. Former Vice President Al Gore’s advocacy for governments to change their carbon output to reduce man made global warming has won him a Nobel Prize AND controversy from detractors saying temperature change is a natural a phenomenon. Most climate scientists –over 90 percent last survey- side with Gore. There was also Isaac Cline who was featured in the book Isaac’s Storm by Eric Larson. A native of Monroe County, Cline grew up fascinated by weather. As an adult he was the U.S. Weather Bureau’s meteorologist in Galveston, Texas when the 1900 hurricane struck the city. This became the country’s largest weather disaster. The book presents a fascinating account of the storm and the times.
There are also those eyewitnesses who keep those weather events alive through their memories. Red Oliver is a former mayor of Moscow, one of many towns that were hit hard in the deadliest tornado day in the state’s history. Sitting at Brad’s Barbecue in Moscow in 2010, he remembered that night fifty-eight years ago and being about 300 yards from the tornado. At the time Moscow was town of about 400 people. “There’s just a few of us left that remember,” he says.
“We were at my father in law’s house watching the Friday Night Fights on TV. Then all of a sudden the television started acting up in every kind of way. Then I heard this roar. My daddy in law said ‘that’s a train.’ I said ‘that ain’t no train!’ so I ran out into the yard and when I did the whole ground was shaking. And I saw a cloud coming through with a ball of fire. It set one house on fire. Everything it passed it wiped clean. It wiped everything except this one house with a chimney and by the chimney there was a dog laying there with some puppies. It was not touched but the whole house and everything was gone. There were some monster pine trees and they were just cut off about four feet high. When it got on past you could hear people screaming. Bloody murder type of screaming. Those really hurt were kind of groaning. We had a truck with hay and put the people in the truck.”
On Old Stateline Road west of the Wolf River “there was a house sitting on the hill. When we got out there the house was separated lying in the road. There was an old lady sitting on top of the house without a scratch. Her husband and grandson were underneath. The couch protected the grandson, but the old man died later. There was a man on Highway 76 looking for his wife that had died. His eyeball was at his cheek.”
“In the Wolf River bottoms you would see washing machines and dryers hanging in the trees. Those pine trees were monster things it took a powerful wind. You still have some of those stumps there but they have sprouted out now. Usually you see tornadoes knock the trees down but these were just gone. If it had come through the main drag it would have wiped the town out.”
From tornadoes to Mountain snows, from sultry summers to the dogwoods of Spring to the colors of fall, the Volunteer State physically and culturally has been shaped by its climate.
National Climatic Data Center “Storm Events”
Smoky Mountain Weather
Information on the 2003 Memphis wind storm
Information on the “fish smell” day in Memphis
Charlier, Tom THE COMMERCIAL APPEAL, August 31, 1989 “Phew! Air Trap Smells Up City.”
Cheatham County Firestorm
CLIMATOLOGICAL DATA National Oceanic and Atmospheric Administration, Tennessee
Southeast Regional Climatic Data Center
Applegate, William B., Runyan, John Jr, Brasfield, Linda, Williams, Mary Lynn. Konigsberg, Charles. Fouche, Charles. "Analysis of the 1980 Heat Wave in Memphis” American Geriatrics Society, August, 1981
The Tornado Project Online