Believable Weather for Forbidden Lands

Based on Swedish weather data

Download PDF Download ODS

This is a weather system for the tabletop roleplaying game Forbidden Lands. It’s based on meteorological data from southern Sweden. The goal of the system is to feel believable and be easy to use. It decides three aspects in one roll of three D6:

A document titled Orsvärn Weather System, with a table and some instructions
Preview of the PDF.

Using the System

  1. Roll a D66 (explained below).
  2. Pick the row in the table with that number, that’s your weather.
  3. Calculate TEMPERATURE.
    • Start with the base TEMPERATURE for the current month of the year, from the Seasonal TEMPERATURE table.
    • Add the Temp difference from your row in the weather table.
    • Subtract one TEMPERATURE if it’s dark according to the “Light & Darkness” table on page 147 in the player’s handbook.
  4. Roll another D6 to determine how many Quarter Days the weather lasts.

A “D66” is when you roll two D6 with one being the ones place, and the other being the tens place. So if you roll a 2 and a 4, you have 24. This works best with two different colored dice to make it easier to distinguish between them.

Some dice

Gameplay Effects

If TEMPERATURE is 5, each HIKING player character must succeed with an ENDURANCE roll every Quarter Day or become THIRSTY.

If TEMPERATURE is 1, all player characters who are not in a camp must succeed with an ENDURANCE roll every Quarter Day or become COLD.

On 65 & 66: For each Quarter Day, all player characters must succeed with an ENDURANCE roll to keep moving. On 66: modify the roll by -2.

Some dice, a playing card


Thank You For Reading

If you want to learn how I made the system, read this blog post.