It’s raining rather hard here in the Philly burbs and it’s my understanding that rain is projected over most of the state for the duration of the day. I know that this rain makes me not want to pack up the FinnMan and leave the house, since it is hard to keep the boy dry on the way to and from the car. I’ll get motivated in a bit, but there’s no question that turnout will be less than it would have been on a sunny day. Most analysts think low turnout favors Sestak, particularly in Philadelphia where the Rendell/Nutter/Brady machine will be putting all their muscle into getting out the vote for Specter. I think weather is actually overblown as a factor though. It seems to me that bad weather actually makes it more important that voters receive personal contact from the campaigns or affiliated groups who are doing GOTV. And Specter has a big advantage there. If Specter needs big margins in Philly, the bad weather might actually help him as lightly-motivated Sestak voters stay home.
In a close election, any slight advantage can be decisive, and it could be that Sestak voters, as a whole, are more highly motivated and less likely to be deterred by a downpour. I just don’t think it’s obvious which candidate will benefit.