I live near the mighty Merrimack River in New Hampshire, which is nearing or over flood stage in some places. As I was checking out the real-time flow stats for the river on the New England Corps of Engineers site, I got this rather ironic error message:

Guess the site must be getting a flood of traffic. (Sorry, had to say it!)
Yeah - I saw that a few
Yeah - I saw that a few times during the overnight hours and did a double-take.
These sites are also good (from a Skywarn/NWS/ARES/Red Cross Disaster perspective)
Storm surge: http://www.ndbc.noaa.gov/maps/Northeast.shtml
Higher tides:
http://tidesonline.nos.noaa.gov/
Stream levels:
http://water.usgs.gov/waterwatch/index.php?map_type=real&state=ma