BRISTOL, TN - AUGUST 21: A fan stands in the rain prior to the NASCAR Sprint Cup Series Bass Pro Shops NRA Night Race at Bristol Motor Speedway on August 21, 2016 in Bristol, Tennessee. The race was delayed due to inclement weather on Saturday, August 20. (Photo by Rey Del Rio/Getty Images)

BRISTOL, TN - AUGUST 20: A severe weather warning is seen on the Colossus scoreboard prior to the NASCAR Sprint Cup Series Bass Pro Shops NRA Night Race at Bristol Motor Speedway on August 20, 2016 in Bristol, Tennessee. (Photo by Rey Del Rio/Getty Images)

BRISTOL, TN - AUGUST 20: A severe weather warning is seen on the Colossus scoreboard prior to the NASCAR Sprint Cup Series Bass Pro Shops NRA Night Race at Bristol Motor Speedway on August 20, 2016 in Bristol, Tennessee. (Photo by Rey Del Rio/Getty Images)

BRISTOL, TN - AUGUST 20: A severe weather warning is seen on the Colossus scoreboard prior to the NASCAR Sprint Cup Series Bass Pro Shops NRA Night Race at Bristol Motor Speedway on August 20, 2016 in Bristol, Tennessee. (Photo by Rey Del Rio/Getty Images)

(FILES) This file photo taken on December 3, 2015 in Orcines shows French Ecologist lawmaker Cecile Duflot at the weather station on the 1,465-metre-high Puy de Dome mountain as she campaigns ahead of the upcoming regional elections in the Auvergne-Rhone-Alpes region. Duflot announced on August 20, 2016 her candidacy to the primary election organised by Europe Ecologie-les Verts for the 2017 French presidential election. / AFP PHOTO / Thierry ZoccolanTHIERRY ZOCCOLAN/AFP/Getty Images

LAS VEGAS, NV - AUGUST 19: The first customer in line, Jamie Weathers of Las Vegas tries on a jacket at the Kanye West temporary PABLO store at the Fashion Show mall on August 19, 2016 in Las Vegas, Nevada. (Photo by David Becker/Getty Images for Bravado)

WRIGHTWOOD, CA - AUGUST 18: Intense flames driven by extreme drought conditions, wind and hot weather sweep over a remote section of the San Bernardino National Forest during the Blue Cut Fire on August 18, 2016 near Wrightwood, California.. An unknown number of homes and businesses have burned and more than 80,000 people were ordered to evacuate as the wildfire spreads beyond 30,000 acres and threatens to expand into the ski resort town of Wrightwood. (Photo by David McNew/Getty Images)

A picture shows a general view of retail shops on Oxford Street in central London on August 18, 2016. Retail sales in Britain, a key driver of the country's economy, rebounded 1.4 percent in July from the previous month's drop, official data showed August 18, 2016, calming fears over any immediate fallout from Brexit. Sales by volume rose sharply following a 0.9-percent drop in June that had been caused by wet summer weather, according to the Office for National Statistics. / AFP PHOTO / JUSTIN TALLISJUSTIN TALLIS/AFP/Getty Images