For purposes of these rules, weather consists of three basic ingredients: temperature, wind, and precipitation. Each of these categories is pre- sented as a hazard. To create a weather condi- tion, just pick a hazard for each and combine
their effects. The hazards are designed so that they do not conflict. You can match any tem- perature effect with any wind effect, and the two function independently of each other. In some cases, you can select more than one hazard for a type. Precipitation covers fog in addition to hail and rain. In addition, you could create a storm that delivers both rain and hail. The sample storms given below serve as a guide to illustrate how you can combine these effects. Common sense serves as your best guide in putting together storms and effects. In addition, the section on long-term weather pro- vides ideas and guidelines for creating sensible weather patterns for an area.
Note that in some cases the weather traits draw on material presented in the core rules. While the basic rules remain the same, they have been adapted to fit into the design and classification scheme presented here.
Keep in mind the standard rules for stacking modifiers and effects. If a modifier does not have a specific label, such as competence, assume that it is a circumstance modifier that stacks with all other types, including other cir- cumstance modifiers.
Precipitation
This aspect of the weather covers rain, hail, snow, and even fog. In addition, a few magical weather effects are included here. These phe- nomena may be the result of arcane instability, holes in the planar structure, or magical or divine curses.
Acidic Rain
Green, sizzling acid falls from the sky, scorch- ing grass and melting exposed rocks, metal, and flesh. These deadly storms can sweep the living creatures from an area, transforming a verdant forest into a dead wasteland in the span of a few days. Acidic storms are a common hazard in wastelands and other areas wracked with strange magical effects. This precipitation type is represented with a series of hazards. Even at its weakest rating, it still presents a potentially deadly threat.
Light Acidic Rain (CR 1): Fortitude save DC
10; 1 minute interval; +0 bonus/interval; 1d6 damage; Special: Acid rain inflicts damage against any armor worn, shields carried, and
clothing. In addition, it leaves behind pools of acid much like rain puddles. Consult the core rules for information on acid exposure. Finally, as it burns away rocks, plants, and other mate- rial, it generates the equivalent of light fog.
Moderate Acidic Rain (CR 3): Fortitude save
DC 15; 1 minute interval; –1 penalty/interval; 2d6 damage; Special: As per light acidic rain, except that the acid creates moderate fog as it burns.
Severe Acidic Rain (CR 5): Fortitude save DC
20; 1 minute interval; –1 penalty/interval; 4d6 damage; Special: As per light acidic rain, except that the acid creates thick fog as it burns.
Fog
Whether in the form of a low-lying cloud or a mist rising from the ground, fog obscures all sight, including darkvision. The extent to which it obscures vision depends on its strength.
CHAPTER ELEVEN: Weather
CHAPTER ELEVEN: Weather
Hail
This precipitation effect can range from small, fine shards of ice to deadly chunks that can hammer a man into unconsciousness. Hail storms are relatively rare and when they strike they usually persist for only a short period of time. Hail storms have no effect on visibility or open flames, as even the fiercest ones create relatively scattered precipitation.
Most hail storms are too light to have any effect on travelers, though they may drive most folk indoors. Usually, they occur as part of other forms of precipitation. However, some hail storms are powerful enough to threaten anyone caught out in the open,
Heavy Hail (CR 1): Fortitude save DC 10; 10
minute interval; +0 bonus/interval; 1d6 non- lethal damage; Special: Creatures caught in this storm suffer a –4 penalty to Listen checks due to the loud din the ice makes as it hits the ground.
Severe Hail (CR 3): Fortitude save DC 15; 1
minute interval; +0 bonus/interval; 1d6 non- lethal damage; Special: Creatures caught in this storm suffer a –4 penalty to Listen and Spot checks due to the thick hail.
Rain
Rainstorms reduce visibility and make it hard- er to use ranged attacks in addition to a variety of other effects. The table below lists the vari- ous rain storm strengths and the modifiers they impose on ranged attacks and Listen, Spot, and Search checks. The modifiers for ranged attacks apply only to bows, crossbows, and other portable weapons. They do not affect siege weaponry.
Light rains are steady drizzles and showers.
They have a 50% chance to extinguish any unprotected flame.
Moderate rains represent the typical storm.
They automatically extinguish any unprotected flames. They cause protected flames (such as those of lanterns) to dance wildly and have a 50% chance of extinguishing these lights.
Heavy rains represent thunderstorms and other
severe but not necessarily dangerous weather. They affect fires as per moderate rains.
Severe rains accompany deadly weather
effects, such as hurricanes and severe thunder- storms. They affect flames as per moderate rains.
Rain Skill Checks and Strength Ranged Attacks
Light –2
Moderate –4
Heavy –6
Severe –8
Meteoric Rain
Fiery stones streak through the sky, slamming into the earth with an explosive force. Meteoric rain pockmarks the land with craters and scorched clearings.
If the characters take shelter from this hazard within a building or other structure, assess damage against it from the explosive blasts. Estimate the roof’s thickness, determine the hit points based on that, and record the damage it sustains each minute. Do not worry about determining the hit points for the entire roof. Instead, this method allows you to use an abstract method to see how long it takes before the storm smashes a hole in the roof. The aver- age roof has hardness 5 and 60 hit points. Once the storm punches a hole in the roof, the build- ing provides a +8 bonus on saves against this threat. Start the process over against the roof’s full hit points. Each time they are reduced to zero, decrease the save bonus by 2 to a mini- mum of 0.