Page life expectancy...with duration

can this alert be configured so only if PLE is below a threshold and stays below the threshold for a "n" seconds, the alert needs to be fired! Most of the time PLE  goes low for few seconds and comes back up immediately. I would configure for this alert to fire if PLE is less than 300 for at least 60 seconds. Can this be done ? Or can this be added for future *** ? Ideally most alerts should have a duration tied to them.