Maybe the storm could be seen building up with various weather effects, like sudden high winds and weird colored lightning strikes in the clouds. Animals freaking out and fleeing for cover should be an ominous precursor, followed by heavy, deep charging sound in the distance. Skies darken at the same time. Then silence. Moments later a brilliant white/blue flash. Followed by what can best be described as having your head ran over by a freight train for 5 minutes.
What i'm trying to say is that i think temporal storms should behave more like Emissions in Stalker Gamma.