Ion storms are natural subspace disturbances. There is nothing you can do to force ion storms to appear or disappear. They move through space at random, and affect ships. The number of ion storms can be configured using IonStormActivity, set that to zero if you do not want to use ion storms.

Ion storms are circles, defined by position and radius. They move through space, with a speed and course that changes over time.

Storms have a voltage measured in MeV, which defines their strength. According to that voltage, storms are grouped into classes:

1 .. 49 MeVClass 1 - Harmless
50 .. 99 MeVClass 2 - Moderate
100 .. 149 MeVClass 3 - Strong
150 .. 199 MeVClass 4 - Dangerous
200 MeV and moreClass 5 - Very Dangerous

With PHost, all players see all ion storms. Every turn, you receive messages reporting the speed and course the storm took this turn.

When ion storms form anew, they start growing. During the growth phase, they shrink in size, but gain strength. When they are strong, they will ultimately start to weaken. During the weakening phase, they get larger but lose strength, until they drop to voltage zero, when they disappear. For compatibility with HOST, growing storms always have odd voltages, weakening ones always have even voltages.