CLIMATE OF THE FLANAESS

On the world of Oerth, local weather is strongly affected by magic, and it is possible that magic even generates or controls the world's climate as well. Certainly, the Flanaess has an unusually long summer and growing season, especially considering the world's large axial tilt, which by rights should produce remarkable seasonal and climatic extremes. Certain deities and their agents specialize in manipulation of the atmosphere, including winds, clouds, rain, heat and cold. Such manipulations are generally meant to keep the weather beneficial to most worshipers of the gods, though the weather can also be used to punish transgressors on a large scale.

Spells cast by wizards and priests can have extraordinary effects on local weather patterns, too, and new weather-altering spells are developed all the time. Some kingdoms appear to deliberately alter local conditions on a day-to-day basis to keep the weather as pleasant as possible. However, there is concern that great or prolonged weather changes using magic result in a backlash, altering conditions elsewhere on the world or even on other planes, particularly the elemental ones. Some areas of Oerth, particularly over the seas, are savaged by storms of extreme violence, perhaps unknowingly driven by magic-use elsewhere.

Beyond this, changes in climate on Oerth are closely related to latitude. In general, a change of one degree of latitude will result in a difference of two degrees Fahrenheit in temperature. Thus, a wizard teleporting from the equator in the jungles of Hepmonaland to the northernmost peninsula of the Land of Black Ice, about 60 degrees north latitude, should experience a sudden drop in temperature of roughly 120 degrees. Local conditions alter this tendency.

The Flanaess, as noted, has an especially good growing season. Temperatures rarely fall below freezing in that part of the Flanaess that is below 45 degrees north latitude (roughly the latitude of Perrenland), except during the two winter months (Sunsebb and Fireseek) and early spring (Readying), and at night during late spring (Coldeven) and late autumn (Ready'reat). Even in the depths of winter, rarely more than a week or two of bitterly cold weather is suffered, with gradual warming after. Summer lasts five or six months in the central Flanaess, that area between 4S and 2S degrees north latitude, approximately the latitudes of the Crystalmists. The climate here is temperate, with snowfall rare south of latitude 35 degrees (just south of Greyhawk).

The coasts usually receive more rainfall and remain cooler in the summer and warmer in the winter than inland areas. Several areas have subtropical conditions, during which the summers are relatively dry but winters bring considerable rain. These areas include the Hold of the Sea Princes, the Pomarj, Ormwal, Idee, the Vast Swamp, Dullstrand, the northern Lordship of the Isles and the Spindrift Isles.

Tropical conditions generally exist everywhere south of 20 degrees north latitude. Affected in particular are the Amedio Jungle, the Tilvanot Peninsula, the southern Lordship of the Isles and all of Hepmonaland. Here, it is hot and rainfall is abundant year-round. Hurricanes are known to occur, generally moving from southwest to northeast except around Hepmonaland, where they usually come directly from the west or southwest, moving against the general flow of air.

The arid Sea of Dust is a blast furnace during the summer, but it remains hot in the daytime all year long and rainfall is rare. This area's horrific weather appears to be maintained by the ancient Stone Circles of Tovag Baragu, in a manner that is not well understood.

High elevations in the Yatils/ Barrier Peaks/ Crystalmists/ Hellfurnaces chain and in the Thillonrian PeninsuWs Corusks/ Griffi/ Rakers chain remain snowbound all year long, with glaciers and alpine conditions above the tree line. Parts of the Hellfurnaces remain above freezing all year long, from active volcanism and the influence of what may be numerous gates to the Elemental Plane of Fire. The Lortmils and Glorioles have only a few snow-capped peaks.

Most regions between 45 and 55 degrees north latitude (the latitudes of the Barrens and the lands of Itiz) count as subarctic, with cool, dry summers during which the ground thaws for only a few months. This region is very close to the Northern Border of Day and Night (as Oerth's arctic circle is called), north of which the length of day and night alter greatly. The Thillonrian Peninsula receives more rain and snowfall than interior areas such as the Barrens, Iuzs homeland and the land of the Wolf Nomads, which are cold steppeland with permafrost tundra farther north. Barbarians of the Thillonrian Peninsula practice limited agriculture.

An exception to the above are those regions adjacent to the Dramidj Ocean, which is known for its unusually warm currents. Zeif, Tusinit, Ekbir and the western half of the lands controlled by the Tiger Nomads are all temperate, with respectable rainfall and the same growing seasons as the central Flanaess. Fog is common in the winter here, as cold air from the north passes over the warm sea. Icebergs are often shrouded in fog.

Prevailing winds in the Flanaess tend to be from the north and northeast in autumn and winter, and from the east and southeast in spring and summer. The wintry north wind is often called "Telchur's breath," after the Oeridian god of the north, and the spring wind from the east is called "Atroa's laugh," for the Oeridian goddess of the east and springtime. Mountain ranges and the like may alter this.

When they flow against high hills and mountains, moisture-laden winds from the east cool, causing rainfall. As the winds cross the hills and mountains, they warm up, retaining their moisture. Thus, the western side of many mountain ranges are dryer than the eastern side. This becomes especially apparent when looking at the west and east sides of the Barrier Peaks/ Crystalrnists/Hellfurnaces chain, though the western side is also more arid because of magical influences. Elsewhere, the Kingdom of Surindi is wetter than the Ahlissan Principality of Naeric to the west, thanks to the Hollow Highlands, but is drier than DuIlstrand and old Medegia, thanks to the Hestmarks. The natural depression found at the joining of these two hilly chains just south of Sunndi forms the Vast Swamp. The eastern Abbor-Alz help keep the Bright Desert dry, yet also feed the Gnatmarsh with abundant rain.