The Boston Marathon will be run tomorrow in temperatures approaching 90 degrees.
The Boston Marathon will be run tomorrow in temperatures approaching 90 degrees. REUTERS

The Boston Athletic Association, organizers of the Boston Marathon, has taken the unprecedented step of urging participants not to compete this year because of record heat expected Monday.

Competitive racers who have qualified for this year's marathon, which is taking place April 16 in Boston, will be allowed to carry over their qualification to the 2013 race over fears that extremely high temperatures could cause problems.

Weather for tomorrow in Boston is predicted to be in the low 70s at the start of the race but will climb to as high as 88 degrees by mid-day.

As a result, the BAA is asking competitors to consider racing next year instead. They are also asking that runners who traditionally follow the main pack, despite not having a bib number, do not participate again this year to give the medics time to concentrate on the actual racers.

What: The 116th Boston Marathon

Where: At 26.2 mile course from Hopkinton, Mass., to Copley Square in Boston.

Who: 27,000 official qualifiers with bib numbers, many thousands more who run the race unofficially.

When: Racing begins at 9 a.m,. for mobility-impaired racers, 9:32 a.m. for the elite women and 10 a.m. for the elite men. Finishers will begin to arrive sometime before 1 p.m.

Watch: You can watch the race live online at http://boston.cbslocal.com/ or you can track the race live online at www.baa.org.