2d6 Weather System
The 2d6 Weather System is a simple context-aware random table, which, while random, keeps the weather from changing too much.
How it works
- First, decide on how often you want to roll for weather. Some prefer to do it for each in world day, while others do it three times per day. Even if you only roll it once per day, it can be rerolled during the day as the result of a random event or similar.
- Roll 2d6 to get the initial weather.
- On subsequent rolls (the next day, or the next watch - which ever you prefer), add the modifier from the row of the previous result to get the new result. So if you rolled a 4 (Rain/snow) on the previous roll, you apply the -1 modifier from that row on this new roll.
- If you roll a natural 7 (that is, the unmodified die roll is a 7), then the weather resets to Overcast - do not add the modifier from the previous result. This simulates a new weather front moving in, and prevents the weather from "getting stuck" for too long at either end of the table.
The 2d6 Weather table
| 2d6 | Weather | Modifier |
|---|---|---|
| 2 or less | Thunder/snowstorm | -1 |
| 3 | Heavy rain/snow | -2 |
| 4 | Rain/snow | -1 |
| 5 | Light rain/snow | -1 |
| 6-7 | Overcast | |
| 8 | Cloudy | +1 |
| 9 | Scattered clouds | +2 |
| 10 or more | Clear skies | +1 |
Remember: An unmodified roll of 7 always ignores the modifiers, and "resets" the weather back to overcast.
An example
Let's run through an example of this system in use.
- We decide to roll weather once per day.
- For the first day, we roll 2d6 with no modifier (since it's the first roll), and get 9 - Scattered clouds.
- The next day, we roll 2d6 and get a 3, but with the +2 from Scattered clouds on the previous roll, we end up with 5 - Light rain.
Then, we continue with this as needed. Any time we roll a natural 7, we ignore any modifiers and reset the weather back to Overcast.
Roll in advance or on the fly?
This system is simple enough that you can roll to generate weather on the fly if you want. But if you decide to roll, say, a week in advance, then it becomes possible to allow PCs to try to predict the weather in advance using a suitable skill or ability.