Yesterday, at 5:45, we received an e-mail from the President indicated work was delayed until 11:00 a.m. Given that classes don't start until 8:00, it seemed like a reasonable timetable. In addition, I did notice a few employees had posted a similar notice on Twitter shortly thereafter. I still decided to make the trip onto campus, and found that 3 of my colleagues did the same. However, they were unaware of the change. They did not check their e-mail in the morning (the horror!!!).
Later that afternoon, given worsening conditions, the decision was made to cancel the rest of the work day so that people could return home safely. However, the communication method had changed. The emergency notification system was activated and I received the message in a number of media - text, phone call, e-mail, message on the organization's web page, and on my Twitter feed. Perhaps, a lesson was learned in the intervening hours about getting the message across.
How are you assuring your employees are getting the news of an impending change in the routine?