I’m currently running a Ultraviolet Grasslands campaign, and like every other campaign I run, I’m really focussed on making the weather a big part of it. Just travelling should be a challenge — not the greatest challenge in the game — but not a literal walk in the park. I want the party hunting for dry firewood, or stuck at a swollen river, or so cold they can’t face breaking camp. Not every single day, obviously, but an “encounter” for me doesn’t have to be “kill a thing that’s appeared with suspicious regularity”.
Evils of Illmire had simple weather rules: each day the GM rolls to see which three hexes have rain, and if they coincide then the rain is considerably worse. Anything beyond that is up to the GM, and if you look through my notes I exposed the party to winter, initially within 5e rules, and then via a minigame.
Adventures in Middle Earth doesn’t regularly use weather directly, but it features in the Journey encounters that are possible, and it provides weather tables to use for flavour if nothing else. This is reasonably in-keeping with the source: there’s some bad weather in Hobbit and Lord of the Rings, but it’s the exception (Caradhras, Misty Mountains) rather than the rule.
I fancied something a bit stronger, and spent a happy few days looking at hexflowers which gives random rolls weighted by history. This means your weather is likely to be similar to what you rolled previously, while still allowing a full range of interesting things to happen.
Then I realised this is great if you’re rolling several times a day, or every day. But actually I only want to roll at most twice a week: that’s the unit of time UVG is normally dealing with. A hexflower then looks like it moves too slowly for me - extreme events could take several months, and then hang around too long!
Weather Tables
Roll 2d4 plus an offset based on your current climate on both tables.
This is about time of year and your world’s geography.
For the first table, we’re increasing in temperature from 1–12, alternating on whether it’s windy or not.
| Roll | Temperature 🌡 |
|---|---|
| 1 | Freezing & windy. Frostbite takes minutes, hypothermia won’t be long after |
| 2 | Freezing. Starting as inconvenient, travellers need special equipment to travel |
| 3 | Biting wind. Coats essential |
| 4 | Cold |
| 5 | Fresh. Provided you keep moving, you’re not even cold |
| 6 | Cool winds |
| 7 | Pleasant. What they say because it isn’t actually nice out |
| 8 | Nice. Like, actually nice? Surprising, isn’t it? |
| 9 | Warm. Travelling is less nice than being still |
| 10 | Hot. ☀️ Unpleasant |
| 11 | Searing wind, feels like an opening an oven |
| 12 | Dangerously hot, being outside unprotected will burn skin or dehydrate rapidly. Movement seems impossible |
And precipitation needs some thinking about; torrential rain when it’s freezing is a blizzard ❄️❄️, for instance. Can it be overcast, and yet dangerously hot? I think so, but no rain will touch the ground.
| Roll | Precipitation |
|---|---|
| 1 | Floods. Everywhere there is hazardous stationary or moving water |
| 2 | Torrential rain. Visibility is reduced, rivers are dangerous, mud |
| 3 | 🌧 Persistent rain, the whole time. Nothing is dry, everything chafes, it’s colder than you’d think |
| 4 | ☔ Heavy showers, but with some respite |
| 5 | Occasional showers, easily ignored |
| 6 | Clammy and damp, never actually rains |
| 7 | ☁ Overcast, navigation by the sun might be hard |
| 8 | ⛅ Mixed sun and clouds, can be a relief in the heat |
| 9–10 | Dry. Water supply becomes critical |
| 11–12 | Arid. You thought it was dry before! |
Climates
Using offsets of 0–4 stay in the table, obviously. I don’t see a problem in going outside of this, decide for yourself what a result of -1 or 13 is. Same as 0 or 12, or something even worse or a wildcard?
Some ideas
| Climate | Temp. | Precip. |
|---|---|---|
| Severe winter | 0 | 2 |
| Damp spring | 2 | 0 |
| Summer | 7 | 6 |
Issues
This might not suit everyone, events like hurricanes or monsoons are hinted at with floods and winds. There’s no options for tornados or hail. Fog 🌫 will occur when it’s cold and damp. But I don’t think that matters for me, I might something like that more story-led.
We’ll see though — I’ll try it for a year.