Weather is given short shrift in most RPGs, including D&D Dungeon Master’s Guide as well as the Pathfinder core rule book. But weather can be a great addition to a wilderness adventure and great flavor in any adventure with some travel. Here’s a simple system that isn’t pointlessly random.

Roll for the weather at the beginning of the adventure. The heroes are unlikely to start on a journey in bad weather, so assume they start in fair weather or something close to it on Day 1. Day 2 is more like the weather you rolled; Day 3 is fully that weather. Then roll for Day 5, so you always know the weather two days out, which helps for characters with weather-sense abilities or if you want to foreshadow the coming change.

You can also want to roll randomly once or twice for the weather between adventures.

Simple Weather

Roll 1d6 for Temperature and 1d6 for Wind & Wet. If both unmodified rolls are natural 1, there’s a fierce storm. This system assumes a temperate region.

1d6	Temperature (winter -1; summer +1)	Wind & Wet (spring -1; summer +1)
0-1	Colder than normal; overcast	Wind; rain/snow ✽
2	Colder than normal; some clouds	Wind; light rain/snow ✽
3	Typical for the season; overcast	Calm; foggy morning
4	Typical for the season; some clouds	Blustery ✽
5	Warmer than normal; clear	Windy ✽
6-7	Typical for the season; clear	Calm

✽ 1d6: 1=morning; 2=afternoon; 3=evening; 4=night; 5-6=overnight.

Dramatic Weather

Here’s a more dramatic weather system, also pretty simple. Drama tip: Roll with advantage in a good region and with disadvantage in an evil region. Life is harder and more desperate in regions with bad weather.

1d20	Winter	Spring	Summer	Autumn
1	Beastly blizzard ✽	Black thunderstorm ✽	Fearsome hail ✽	Pounding rain ✽
2-3	Heavy snow/rain ✽	Punishing rain ✽	Scorching heat	Snow ✽
4-5	Bone-chilling wind	Relentless drizzle	Relentless drizzle	Relentless drizzle
6-7	Crackling frost	Crackling frost	Heat	Whipping winds ✽
8-9	Cold with dense fog	Heat	Humid	Humid
10-14	Oppressive gray skies	Morning mist	Blustery ✽	Oppressive gray skies
15-20	Fair (chilly)	Fair (cool)	Fair (warm)	Fair (cool)

✽ 1d6: 1=morning; 2=afternoon; 3=evening; 4=night; 5-6=overnight.

Climate

If you want to account for climate in different regions, use this simple table.

Month	Midlands	North	South	Desert
January	Winter	Winter	Autumn	Spring
February	Winter	Winter	Spring	Spring
March	Spring	Winter	Spring	Autumn
April	Spring	Spring	Spring	Summer
May	Spring	Spring	Summer	Summer
June	Summer	Spring	Summer	Summer
July	Summer	Summer	Summer	Summer
August	Summer	Autumn	Summer	Summer
September	Autumn	Autumn	Summer	Summer
October	Autumn	Autumn	Autumn	Summer
November	Autumn	Winter	Autumn	Summer
December	Winter	Winter	Autumn	Autumn