The climate of the Brevoy can be described as typical Avistani continental influenced climate with warm, dry summers and fairly severe winters. The weather is often breezy and humid due to the proximity of the Lake of Mists and Veils. The Lake also contributes to typical heavy snowfall in winter and creates heavy fog in both Fall and Winter.

Abadius is the coldest month with daytime temperatures usually around -5°C (23°F), but in some cases winter months can be much colder with temperatures far below zero, about -20°C (-4°F) or lower and strong, cold northeasterly winds. Heavy snowfall or even snowstorms are also common. Annual average snowfall is 250 cm (98 inches), with snowfall accumulations of 55-70 cm (22-28 inches) per winter month not uncommon. A typical year will see snow for at least 6 months, from Neth to Gozran, with occasional snow in Lamashan or Desnus.

In summer daytime temperatures reach 20-25°C (68-77°F), but sometimes quite higher, 30°C (86°F) or more. In most of the time it is dry weather with sunny spells, rain often falls with sometimes heavy thunderstorms that can occur at the end of the day. Erastus is the warmest month with an average temperature of 18°C (65°F). Annual Precipitation is about 600-800 mm (24-32 inches).

Generally, the weather is best Desnus-Rova, when days are warm and the nights are cool, although it rains more in Spring than in summer. Autumn and Winter are usually chilly and wet, sometimes snowy and often foggy.

Summer days see sunlight for up to 17 hours with nautical twilight throughout the nighttime hours. Winter days are inversely short, with late sunrises and full dark falling before dinner time. Further, winter days tend to be grey and overcast.