Mary Keitany of Kenya owns the women's-only marathon world record, having run 2:17:01 to win the 2017 London Marathon. That ranks her second overall all-time. In 2018 she won the New York City Marathon in 2:22:48. She had been leading the 2018 London Marathon, aiming for the overall world record, but she faded in the final stages of the race and finished fifth in 2:24:27.

Vivian Cheruiyot of Kenya used a more conservative early pace to win the 2018 London Marathon in 2:18:31. That ranks her seventh on the all-time performer list. She followed that with a runner-up finish to Keitany in New York City, running 2:26:02.

Gladys Cherono of Kenya won the 2018 Berlin Marathon in 2:18:11. That ranks her sixth on the all-timer performer list. Prior to her Berlin win, she finished fourth in London, running 2:24:10.

Brigid Kosgei of Kenya won the 2018 Chicago Marathon in 2:18:35. That ranks her ninth on the all-time performer list. She also finished runner-up at the 2018 London Marathon, running 2:20:13.

These four women represent some of the best marathoners ever. Not only are they fast, but they have seen recent success in the world's biggest marathon races. In total, there are six women in the field who have broken 2:20 in their careers. And that is after the withdrawal of Tirunesh Dibaba, who is ranked fifth on the all-timer performer list, due to pregnancy.

The current weather forecast, from Weather.com, predicts a cool and cloudy conditions with light winds. In other words, it could be the perfect conditions to run fast, something all of the above women are capable of doing.