Ion storm
- Most common variety of notable interstellar weather phenomena
- Also known as "magnetic storm", usually in older references (SGR Novel: The Valiant)
- Strong concentration of charged plasma caught within internally self-sustaining magnetic field lines (TNG Novel: The Buried Age)
- Often created as a result of extreme stellar activity (TOS: "The Galileo Seven"; DS9: "For the Uniform"; "The Emperor's New Cloak")
- Can also be created by other highly-energetic occurrences within existing strong magnetic fields, such as warp core breaches (ENT Novel: Beneath the Raptor's Wing)
- Coronal mass ejections an especially powerful source (VOY Short Story: "Brief Candle")
- Ion storms naturally dissipate over time as energy is expended, reducing strength of self-generated magnetic fields, but for powerful storm fronts this can take days if not weeks (TNG Novel: The Buried Age)
- Known for disrupting or damaging starship systems (VOY: "Dark Frontier")
- Sufficiently powerful ion storms can cause hull damage or loss of hull integrity through electrical discharge and/or disruption of structural integrity systems (DS9: "Accession"; TOS: "Court Martial")
- Powerful EM fields can cause overloads or malfunctions in shipboard electrical systems or computers (ENT: "Doctor's Orders"; TOS: "Mirror, Mirror")
- Magnetic containment systems can be disrupted by high external magnetic fields, resulting in engine damage or containment failure (ENT: "Oasis")
- Can disrupt or block communications or sensors via signal distortion, noise overwhelming signal (DS9: "The Die is Cast"; Star Trek: Nemesis)
- Ion storms rated on incremental scale from 1 up to at least 12 (TNG Novel: The Buried Age)
- Force 2 storms result in minor hull vibrations, no appreciable damage to starships with active structural integrity systems (TOS: "Court Martial")
- Force 7 storms capable of posing severe risk to Constitution-class vessels (TOS: "Court Martial")
- Force 8 storms capable of posing severe risk to heavy cruisers, Intrepid-class vessels (TNG Novel: The Buried Age; VOY: "Once Upon a Time")