How to change the time and weather

Tired of the rain, or want permanent daytime? Two commands cover it, and both take effect instantly from the Console with no restart.

Time

time set day        morning, the usual choice
time set noon       sun directly overhead
time set night      start of night
time set midnight   darkest point

To stop the sun moving at all, turn off the day cycle:

gamerule doDaylightCycle false

Time then stays wherever you last set it. Set the time you want first, then freeze it.

Weather

weather clear     stops rain and storms
weather rain      starts rain
weather thunder   starts a thunderstorm

To stop weather changing on its own:

gamerule doWeatherCycle false

You can also add a duration in seconds, so weather clear 1000000 gives you a very long dry spell without touching the gamerule.

Things that catch people out

• Freezing the day cycle also freezes anything that depends on time, including phantom spawning and villager schedules.
• Weather is per dimension. Clearing it in the Overworld does nothing in another dimension, though the Nether and End have no weather anyway.
• Beds still need night. With the day cycle frozen at noon, players cannot sleep.

These are per-world settings and they persist across restarts, so you only need to set them once.

More toggles like these: How to use game rules.