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Mastering the Wild / Weather in the Wilderness

Weather Baseline

Source Ultimate Wilderness pg. 165
When determining weather for a region in your campaign, your first step is to establish the weather baseline for the region. The weather baseline is influenced by the region’s climate (this sets the baseline temperature), elevation (this provides the baseline precipitation intensity), and season (this affects the temperature and dictates the baseline precipitation frequency).

Climate

Source Ultimate Wilderness pg. 165
Your first step in determining a region’s baseline weather is to decide upon the region’s climate. Climate is split up into one of three categories: cold, temperate and tropical. These types correspond to the three climate categories used in monster entries in all of the Pathfinder Bestiary volumes (note that a fourth category, extraplanar, is not a factor in determining weather for Material Plane worlds).

The baseline temperature range for each climate category is given below, and is further refined in Temperature Variations and Precipitation. These baselines are also presented in Table 4–12.

Cold: A cold climate is found in the extreme northern or southern regions of the world at latitudes greater than 60 degrees (approximately 2,000 miles from a pole). In these polar regions, temperatures often remain below freezing throughout the majority of the year. The baseline temperature in this climate is cold, ranging from 20º F in the winter, to 30º F in the spring and fall months, and up to 40º F in the summer. For regions within 500 miles of the pole, the baseline temperature is 10º F colder than the seasonal average. For regions within 250 miles of the pole, the baseline temperature is 20º F colder than the seasonal average. Because cold air tends to be drier than warm air, reduce the frequency and intensity of precipitation by one step in cold climates.

Temperate: Temperate climates stretch between the polar regions and tropical regions of the world, generally at latitudes between 60 degrees and 30 degrees. The baseline temperature in this climate ranges from 30º F in winter, to 60º F in spring and fall, and all the way up to 80º F in summer. Precipitation frequency is not altered as a result of a temperate climate, but it can still be altered as a result of other factors such as the elevation or season (see below).

Tropical: The tropics exist to either side of the world’s equator, extending north and south for about 30 degrees of latitude in either direction. Tropical regions tend to be warm and humid, with a baseline temperature ranging from 50º F in winter, to 75º F in spring and fall, and up to 95º F in summer. Because warm, humid air produces a great deal of precipitation, increase the frequency and intensity of precipitation by one step in this climate.

Table 4-12: Climate Baselines

Climate	Winter Temp.	Spring Temp.	Summer Temp.	Fall Temp.	Precipitation Adjustment
Cold	20º F	30º F	40º F	30º F	Decrease frequency and intensity by one step
Temperate	30º F	60º F	80º F	60º F	—
Tropical	50º F	75º F	95º F	75º F	Increase frequency and intensity by one step

Elevation

Source Ultimate Wilderness pg. 166
While the climate sets baselines for temperatures, elevation plays a key factor as well. Elevation can affect the baseline temperature, and it sets the baseline intensity of precipitation in the region, as explained below and displayed in Table 4–13: Elevation Baselines.

Sea Level: Temperatures in sea-level and coastal regions are 10º warmer. Sea-level regions also tend to have more precipitation than areas of higher elevation, so the baseline precipitation intensity in a sea-level region is heavy.

Lowland: Lowlands are areas of low elevation not near the coast, generally at an elevation of 1,000 to 5,000 feet. This elevation range does not alter baseline temperatures. The baseline precipitation intensity in lowlands is medium.

Highland: Highlands include regions with elevations above 5,000 feet. Decrease baseline temperatures in highlands by 10º (although in particularly arid and flat regions, you should instead increase the baseline temperature by 10º, while in particularly high-altitude regions such as significant mountain ranges, you should instead decrease the baseline temperature by 20º). The frequency of precipitation is decreased by one step, and baseline precipitation intensity is medium.

Table 4-13: Elevation Baselines

Elevation	Altitude Range	Baseline Temp. Adjust.	Baseline Precipitation Intensity
Sea level	Below 1,000 ft.	+10º F	Heavy
Lowland	1,000 ft. to 5,000 ft.	—	Medium
Highland	Above 5,000 ft.	-10º F	Medium (decrease precipitation frequency by one step)

Season

Source Ultimate Wilderness pg. 166
A year has four seasons—spring, summer, fall, and winter— each of which lasts about 3 months. Season plays an important part in dictating a region’s baseline temperature (as noted in each climate and in Table 4–14). It also dictates the baseline precipitation frequency in a region before applying adjustments due to climate or elevation. In most regions with cold and temperate climates, precipitation frequency is intermittent during spring and fall, common during the summer, and rare during the winter. In most regions with tropical climates, precipitation frequency is common during spring and fall, intermittent during the summer, and rare during the winter.

On worlds with a tilt in their axis, the seasons are typically reversed between northern and southern hemispheres. While it is the height of summer in the north, the areas south of the equator are in the depths of winter.

Table 4-14: Seasonal Baselines

Season	Cold or Temperate Climate Precip. Frequency	Tropical Climate Precip. Frequency
Spring	Intermittent	Common
Summer	Common	Intermittent
Fall	Intermittent	Common
Winter	Rare	Rare

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