Things are looking up already :-). This is the Monday morning forecast for Boston:

Monday: A steady, heavy rain in the morning. Showers continuing in the afternoon. High near 45F. Winds ESE at 20 to 30 mph.

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And here is an article from the Boston Globe:

Marathoners: Ready, set, shiver
Authorities brace for weather, mobilize medical help

By Brian MacQuarrie, Globe Staff | April 14, 2007

With a nasty brew of heavy rain, cold, and headwinds forecast for Monday, authorities are scrambling to mitigate the misery of 23,000 runners in what could rank among the worst conditions in the history of the Boston Marathon.

More than 1,200 medical personnel will line the 26.2-mile course, waiting to treat runners for hypothermia or injuries. School buses will be converted to emergency shelters, and communities along the route are considering using public buildings as heated sanctuaries for shivering dropouts.

"It's extremely disappointing," race director Dave McGillivray said of the forecast, which called for heavy rain and easterly winds as high as 20 miles per hour.
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