You can follow along live on NASA TV. If the launch is not cleared by 12 noon EST, it will be scrubbed for the day.
Update 10:49 EST: Launch control just said the brief opening in the weather they were expecting for just minutes from now is looking much less clear than it did a few minutes ago. Winds at the launch pad are also gusting above 20 knots, which is the maximum wind speed tolerated for a launch. They're now holding for a 11:00 EST resume of the countdown.
Update 11:05 EST: Now it's 11:10 EST.
Update 11:18 EST: Not looking good for launch today.
Update 11:20 EST: And it's scrubbed--same time tomorrow is the schedule now.