Weather Rules
These rules are meant to be a simpler alternative to the weather rules in D&D and Pathfinder. There are five climates and five temperatures. The five temperatures levels are Very Hot (VH), Hot (H), Moderate (M), Cold (C), and Very Cold (VC).

The following table indicates normal weather, given season and climate.

ClimateD/NWinterSpringSummerAutumn
ArcticDayN/A (0)C (2)M (4)C (2)
NightVC (4)C (2)N/A (0)VC (2)
Sub-ArcticDayC (1)C (2)M (3)C (2)
NightVC (3)C (2)C (1)C (2)
TemperateDayCMMM
NightCCMC
WarmDayMMHM
NightCMMM
HotDayMHVHM
NightMMHM

In arctic regions, the sun never sets in Summer and never rises in Winter. Arctic and Sub-Arctic climates also show in parentheses how many 6-hour watches for day and for night. Assume 2 watches each for day and night for warmer climates, regardless of season.

For each day while the PCs travel, roll two 10-sided dice each day for unusual weather. If the PC's are in town or are otherwise spending most of their time indoors, don't bother rolling for weather. Just assume the normal weather. By "unusual", I just mean it will be different than the Climate/Season table above. For each die, determine which 6-hour watch, if any, will have unusal weather:

1Watch 1
2Watch 2
3Watch 3
4Watch 4
5-10None

Example: You roll a 2 and an 8. That means there is just one watch, Watch 2, with unusal weather.

If both rolls indicate unusual weather in the same watch, roll twice on the table below and combine the effects. Since you roll at the beginning of each day, you should roll these dice secretly so your players don't become experts at predicting the weather! :)

For each watch with unusual weather, roll d10 and adjust the normal weather as follows:

12 levels colder
2-41 level colder
5Rain or snow
6Wind
7-91 level hotter
102 levels hotter

If the adjustment from the normal weather indicates colder than Very Cold, just use Very Cold. If the adjustment from normal indicates hotter than "Very Hot", just use "Very Hot".

Very cold and very hot weather requires special gear or there are damage effects from exposure on failing fortitude saves.