Upright meaning
Hail: a disruption you did not choose. It passes, and what it breaks makes room for something truer to grow.
Reversed (merkstave)
Hagalaz looks the same either way up, so it has no reversed meaning. Read it upright every time.
A question to sit with
What would you rebuild differently if the storm cleared the ground?
Its ætt
Hagalaz belongs to Heimdall's ætt, the runes of forces outside your control and the growth they force.