Thunderstorm



Thunderstorms are a somewhat common and dangerous weather condition.

Behavior
Thunderstorms are a semi-common temporary, global occurrence that can happen randomly at any time, within the Overworld. The exact type of precipitation during a thunderstorm will vary depending on the temperature of the current biome, and the current altitude, too.

Thunderstorms may occur randomly, as rain or snow storms worsen. The average storm lasts 0.5 – 1 Minecraft day, and there is a 0.5 to 7.5 day delay between thunderstorms. They can be skipped entirely with the use of a bed.

Effects
As with rain and snow, the sky is darkened and the sun, moon, and stars are no longer visible. Thunderstorms darken the world, causing light from the sky to decrease to a level of 10 in full daylight (however, brightness is closer to a level 11.5 and is tinted blue). The clouds darken from white to a dark gray, although clouds themselves do not precipitate or create lightning. While the sun is not visible during rain, the glow associated with sunrise and sunset is still visible.

Unlike during regular rainstorms or snowstorms, the light level from the sky is treated as if it were 5 for the purposes of hostile mob spawning, which allows hostile mobs to spawn at any time of the day.

Lightning
Lightning is a lethal element to thunderstorms. Lightning momentarily increases the sky light's brightness to slightly greater than full daylight.



Lightning strikes randomly and creates fires where it strikes. Such fires act normally, igniting all flammable materials, detonating TNT, and even activating nether portals. The lightning itself however, is not destructive and will not destroy blocks. While most fires are extinguished by the rain, areas that block rain can allow the fire to spread, and any netherrack lit by lightning will not be extinguished by the rain.

Most entities struck by lightning are dealt damage, and are set on fire, which may cause additional damage. If lightning strikes a pig, it turns into a zombie pigman. If lightning strikes a creeper, it becomes charged. If lightning strikes a villager, it transforms into a witch.



Lightning may randomly spawn a "skeleton trap" skeletal horse, with a chance of 0.75–1.5% chance on Easy, 1.5–4% on Normal, and 2.8125–6.75% on Hard, depending on the regional difficulty.

If the player is killed by a lightning strike, the death message will read "[player] was struck by lightning." However, this message will not display if the player was killed by the fire created by a lightning bolt.

Lightning may be manually summoned with the command. While it is summoned as an entity, it cannot be referred to by commands or selectors. This may have changed as of 1.12.2.

Thunder
Thunder is a sound event that occurs every time lightning strikes. Every player in the same world where lightning struck will hear the thunder at the same time, regardless of distance from the strike.

The ability to hear thunder affects multiplayer, as it is possible to hear lightning strike at someone else's base or use a modded Minecraft client to determine the direction of every strike in the world the player is in. Using the direction of strikes, it is possible to triangulate the coordinates of lightning strikes. Some of the lightning strikes may be in permanently loaded chunks rather than players, but many will be in chunks loaded by players, and it is likely that those players will be close to their base. This means it is possible to use thunder to find other players (and possibly their base) over any distance.

Lightning mechanics
For each loaded chunk, every tick there is a $1/100,000$ chance of an attempted lightning strike during a thunderstorm.

When lightning is to strike, random X and Z coordinates within the chunk are chosen, and the block just above the highest block that is liquid or blocks movement is chosen for the lightning strike. Then if there are any living entities that can see the sky in a 3×3×h region from 3 below the target block up to the world height, one such entity is selected at random and the lightning target is moved to the block the entity is standing in.

The target block is checked again for the following conditions: If these conditions pass, lightning strikes.
 * Target block can see sky.
 * Rain (not snow) is falling in the target block.
 * Thus, lightning does not naturally strike within cold biomes, or biomes where it does not rain (except in the Console Edition).

When lightning strikes, all entities within a 6×6×12 region horizontally centered on the northwest corner of the target block with the bottom edge 3 below the target block are struck by lightning. Multiple passes are made over this region, so items dropped during an earlier pass may be destroyed during a subsequent pass; damage immunity usually prevents struck mobs from taking more than damage. Non-solid blocks (such as redstone, torches, and snow layers) are not directly affected by lightning.

Trivia

 * In Bedrock Edition, If the player leaves the world during a thunderstorm and rejoins, it would only be raining.
 * Lightning, unlike other weather effects, does not have an image file associated with it. Thus, it is coded directly into the game engine, allowing for dynamic, realistic lightning.
 * In Bedrock Edition, lightning strikes closer to the player more often than in Java Edition and Legacy Console Edition, due to spawn distance limits.
 * If multiple lightning bolts strike a single villager at the same time, the number of witches spawned as a result is equal to the number of lightning bolts, making it possible, but ridiculously unlikely, to get multiple witches from one villager. This also works with pig-to-pigman transformations, but not creeper-to-charged transformations as the latter is just a change of state rather than a new entity creation.
 * The player cannot see mobs, water, glass, etc., through lightning.
 * In Legacy Console Edition, If the player leaves the world with Weather Cycle on during a thunderstorm, it would look like it's only raining, even if it is technically still a thunderstorm.