Janakota: Weather

Dynamic weather generation for a jungle island.

This is my take on Daniel Sell’s Six Dimensional Weather for my jungle island setting of Janakota. I’ve made a few tweaks of my own, but the idea is the same: you pick a spot and begin rolling to generate weather. Travel across Janakota is supposed to be difficult, not least because of the chaotic weather. This generator reflects that.

Weather Generation

I break down each day into six 4-hour Watches. This generator is intended to generate distinct weather for every Watch, not each day.

The default die is a d8. A result of 1 moves the weather a single hex upwards and subsequent results continue on clockwise. Results of 7 or greater keep you in the same hex. Some hexes specify a different die – larger dice make the hex stickier, the weather more persistent. Smaller dice make the weather more fleeting.

Some hexes are split. The top-left result applies during the day and the bottom-right result applies at night.

Some hexes have walls. If a result leads you into a wall, “slide” to the nearest hex. Some walls are marked by an X. Treat these the same as a roll of 7+. Some walls are marked by arrows – these can be traversed only in the direction indicated by the arrow.

All these rules contribute to the chaos – but some patterns do emerge. Sporestorms and Spiderblooms are rare but when they happen they’re likely to stick around for a while. Superblooms are rare and fleeting. Typhoons are uncommon and always in the midst of a deluge of rain.

Weather Types

Here’s a closer look at the types of weather on Janakota. A little context: you must roll equal to or less than a target number but above your Fatigue to succeed any given check. Resilience is essentially HP.

Weather Description Effects
Rain A light rain pelts down. It’s a bit tiring to deal with. +1 Fatigue
Downpour Rain pours down. Rivers swell and most creatures seek shelter. +2 Fatigue, rivers impassable, resting impossible
Typhoon Wind and rain assault the island. All but the most desperate shelter until it passes. +2 Fatigue, rivers impassable, resting impossible, tents useless
Wind Heavy wind scours the landscape. +1 Fatigue
Fog A thick fog hangs to the ground. Navigation is difficult. +1 Fatigue per 5 km traveled
Ash A cloud of choking volcanic ash descends on the area. +1 Fatigue and -1 Resilience per 5 km traveled
Clear Clear skies – a beautiful sight! None
Burning Sun The sun scorches your skin. +1 Fatigue
Dead Air The air is hot, still, and muggy. Bugs swarm everywhere. +1 Fatigue, -1 Resilience
Superbloom Everything in the area sprouts blooms. Plants, tree stumps, creatures. ???
Sporestorm A storm of fungal spores overtakes the area. ???
Spiderbloom A mass of floating spiders rides the wind. ???

Superblooms, Sporestorms and Spiderblooms require a bit more thought. I want them to have a much more significant impact on the world than the other types of weather.


And here’s a week’s worth of random generation. The weather soon turns to torrential rain and gets dangerously close to a typhoon before settling into an extended Sporestorm.

Day 0-4 4-8 8-12 12-16 16-20 20-0
Monday Fog Rain Clear Clear Skies Dead Air Dead Air
Tuesday Dead Air Rain Downpour Downpour Rain Rain
Wednesday Rain Fog Rain Rain Downpour Downpour
Thursday Rain Rain Rain Rain Downpour Downpour
Friday Downpour Rain Rain Rain Rain Rain
Saturday Fog Rain Downpour Wind Wind Sporestorm
Sunday Sporestorm Sporestorm Wind Sporestorm Sporestorm Sporestorm


The last critical piece of this system is gear. Gear to protect yourself from all this nasty weather. Here are a few examples.

Item Description Effect
Cloak A simple waterproofed cloak. Prevents 1 Fatigue from rain unless resting.
Feather-Coat A coat of giant feathers. Very waterproof. Prevents 2 Fatigue from rain unless resting.
Tent A small, burly shelter. Prevents all Fatigue from rain while resting.
Sunjelly A pouch of sweet-smelling jelly to be smeared on the skin. Prevents all Fatigue from sunburn.
Bugjelly A pouch of sharp-smelling jelly to be smeared on the skin. Prevents all Fatigue and Resilience loss from bug bites.
Ashmask A face covering of finely woven fibers. Prevents all Resilience loss from ash.

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Contact: jason@anywhither.com