HOPKINTON (CBS) – The 121st running of the Boston Marathon could end up being a very warm one. Heat will likely be the top concern for the 30,000 runners in this year’s race.
Related: Boston Marathon Guide
Temperatures are expected to be well into the 60’s for most of the race route, under mainly sunny skies.
That’s great for the one million spectators, but not the cool, cloudy conditions most marathoners prefer.
Check: Latest Weather Forecast
Everything will begin with the mobility impaired competitors starting at 8:50 a.m. They’ll be followed by the men’s and women’s wheelchairs and hand cycles before the elite women leave Hopkinton at 9:32 a.m. The Boston Athletic Association says this year’s field of 30 hand cycle entrants will be the largest ever.
The elite men will start at 10 a.m., which also marks the start of the four waves of runners. Each of those has about 7,500 men and women. The final wave is scheduled to leave at 11:15 a.m.
CELEBRATING 50 YEARS
The men’s and women’s winners from 1967, Dave McKenzie and Bobbi Gibb, will be co-grand marshals of this year’s race. McKenzie is the only man from New Zealand to win the Boston Marathon.
Gibb is the first woman to ever finish Boston. She was also grand marshal last year.
Kathrine Switzer, who has been part of WBZ-TV’s marathon coverage team for 30 years, will run the race Monday to mark her own 50th anniversary. She was the first woman to pin on an official race bib and run the Boston Marathon in 1967, when it was for men only.
Race co-director Jock Semple tried to throw her off the course in what became an iconic photograph.
AMERICAN ELITE RUNNERS
The big news among the elite runners is that Marblehead’s Shalane Flanagan won’t be running this year because she’s hurt. She fractured a bone in her lower back while training in the snow in Portland, Oregon.
The good news – she’ll be part of WBZ-TV’s marathon broadcast team.
Related: Mile-by-Mile Course Guide
The top American runners include men’s 2014 champion Meb Keflezighi, who will be running his last Boston Marathon, two-time Olympic medalist Galen Rupp, and two-time Olympian Desiree Linden of California.
Linden is the Americans’ best hope of getting a win in the women’s race, where a U.S runner hasn’t won in more than 30 years. In 2011, she was part of arguably the most thrilling women’s race ever in Boston, finishing second by just two seconds to Caroline Kilel. Linden finished seventh at the 2016 Olympic Marathon.
Rupp is making his Boston debut. He won the bronze medal at the 2016 Olympic Marathon and finished fifth in the 10,000 meters.
6 FORMER CHAMPIONS
Keflezighi is one of 6 former Boston Marathon champions in this year’s field.
Three are from Ethiopia – 2016 men’s winner Lemi Berhanu Hayle, 2016 women’s winner Atsede Baysa and 2014 winner and course-record-holder Buzunesh Deba.
Wesley Korir, the 2012 champion, is back along with fellow Kenyan and 2015 Boston winner Caroline Rotich.
Also keep on eye on two other Kenyans – marathon world record holder Dennis Kimetto, who ran 2:02:57 in Berlin in 2014, and Edna Kiplagat, a London, New York City and Los Angeles marathon champion.
WHO TO WATCH
Former women’s hockey star Denna Laing will be in her first Boston Marathon.
Laing, who is in a wheelchair following a terrible accident on the ice at the Women’s Winter Classic last year, will be paired with former NHL player Bobby Carpenter. They’re raising money for Journey Forward in Canton, a center for people with spinal cord injuries.
Thousands of men and women will run for local charities.
Official charities raised $30.6 million in last year’s race.
EYES IN THE SKY
Security along the course will be tight once again, but this year authorities will be getting help from two drones flying over Hopkinton for the start of the race.
Several roads in the eight towns along the course have been shut down for the marathon.
You can read more about that and MBTA changes for the day here.
WBZ-TV is the exclusive local broadcaster of the Boston Marathon. Pre-race coverage begins at 7 a.m. followed by race coverage at 9 a.m. WBZ-TV’s coverage will be streaming on CBSBoston.com beginning at 9 a.m. The stream is limited to New England. You can also listen to the race on WBZ NewsRadio 1030 beginning at 9 a.m.