Cooler temperatures begin this week as a polar vortex brings much colder conditions with the chance of snow for Snowdonia, Ogwen Valley, North Wales on 22nd October 2018. The Ogwen Valley and Tryfan Mountain looking splendid in the Autumn sunrise. (Photo by DGDImages/Alamy Live News)

A teenager reacts as she receives a shot of the Sinovac vaccine for COVID-19 during a vaccination campaign at a school in Denpasar, Bali, Indonesia on Monday, July 5, 2021. (Photo by Firdia Lisnawati/AP Photo)

Third place: the rear leg, claw and respiratory trachea of a louse (Haematopinus suis). (Photo by Frank Reiser/Nassau Community College/Nikon Small World Photomicrography 2021)

A hiker admires the view as Mt. Etna, Europe's largest active volcano, erupts in the background, in the Bove Valley of Etna Park, on the eastern slope of Mt. Etna, in Sicily, southern Italy, Sunday, July 4, 2021. Since Feb. 16, 2021, Mt. Etna has begun a series of eruptive episodes. (Photo by Salvatore Allegra/AP Photo)

A Bengal tigress who gave birth to four cubs at the Guadalajara Zoo, Jalisco state, Mexico runs at the zoo on October 5, 2021. (Photo by Ulises Ruiz/AFP Photo)

Sunset at Walakiri Beach, Sumba in East Nusantenggara, Indonesia in 2019. (Photo by Aries Hendrick Apriyanto/Rex Features/Shutterstock)

Participants run through coloured powder during the Colour Run race in Moscow, Russia on June 5, 2022. (Photo by Maxim Shemetov/Reuters)

A red squirrel leaps over a gray squirrel after the larger squirrel became annoyed with its territory being encroached upon, Saturday, May 28, 2022, in Freeport, Maine. (Photo by Robert F. Bukaty/AP Photo)