Game Day: Weather in RPGs

As we head into the heart of winter, weather becomes a much bigger concern for my real-world game days. Bad snow stormed scuttled many a Game Day over the years, though thankfully now we can call back to Roll20 if necessary.

Just as a Nor’easter can play havoc with our ability to throw dice, so can weather affect our in-game characters.

In fact, I make sure it does.

Random weather generation in the World of Greyhawk goes back to the Glossography from the 1983 boxed set. It includes a number of tables for generating weather, modified by terrain (e.g. coastal, mountains) and latitude. I used the charts sporadically in the early days of my campaign because it was an intensely manual (if fun) process. Today, I use the Weather Forecaster for Greyhawk World. It randomly generates a month’s worth of weather, using the Greyhawk calendar and all of the appropriate modifiers. it also incorporates the phases of Greyhawk’s two moons: Luna, which is white and large like our own, with a monthly cycle, and Celene, which is smaller, blue, and has a quarterly cycle.

I dump the results into a Google Doc, and then add columns for in-campaign events (e.g. social drama on the streets of Saltmarsh) and campaign notes (e.g. Chapter 5 started on this day and ended on that day). Combining this with Saltmarsh’s own random tables (e.g. fishing yields) creates instant stories, like the time when two days of massive thunderstorms (clearly a tropical storm) caught the town’s fishing fleet at sea. The town residents found themselves trapped indoors because of the heavy rains, and the various factions in town were forced to come into contact with one another … with the player characters in between.

The weather has inspired other stories over the years, including a multi-day blizzard that unexpectedly hit the fledgling frontier town of Obsidian Bay. The storm caught the players out in the countryside, forcing them to take refuge in an ogre-infested cave for several days, eating one of their horses to stay alive. Once they returned to the city, they found the town devasted by the storm. Much of its simple wood-and-thatch structures were destroyed, and the people were suffering from cold-induced maladies. The humanitarian crisis inspired the heroes to undertake a diplomatic mission to a nearby country to solicit aid. It ended up being one of the more memorable arcs in that campaign and it was all because of a few throws of the virtual dice.

The weather doesn’t need to drive the story; it can also influence it. Like many games, Dungeons & Dragons includes skill and combat modifiers based on weather and other environmental effects. A ho-hum fight against goblins can become a lot more challenging when whipping rain blinds the combatants, sudden gales force arrows off course, and the mud-slicked ground turns a gentle slope into a treacherous footing. It’s well worth checking out the weather rules for your own games to see how they might be used in your encounters.

Weather Generators

Automated Generators

Pen-and-paper-based Generators

Weather Resources

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Lightning Storm from the Clouds in Dee Why, New South Wales, Australia. Credit:

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