Travel time: Year-round
Brno, the capital of South Moravia, features a moderately continental climate. Situated at an elevation of approximately 200 meters, it enjoys a slightly warmer and drier environment than the Bohemian regions to the west, thanks to its position in the Dyje-Svratka Valley. Travelers can expect distinct seasonal transitions and a weather profile characterized by stability punctuated by dramatic summer storms.
Brno's weather often follows a predictable rhythm, particularly in the warmer months. Mornings typically begin with clear skies and a refreshing crispness, especially in the peripheral areas like the Brno Dam (Brněnská přehrada). As the sun reaches its zenith, temperatures climb steadily, peaking in the late afternoon.
In summer, this build-up often culminates in a "daily cycle" where heat leads to late-afternoon thunderstorms. These storms can be intense but brief, quickly clearing the air for mild, pleasant evenings. In winter, temperature inversions are common; while the city center might be trapped under a layer of gray fog or low clouds, the surrounding hills (such as Hády or the Pavlov Hills further south) may enjoy bright sunshine and warmer temperatures.
Spring is a season of rapid transformation. March often begins with the remnants of winter—occasional frost and "light" snow—but by May, daytime highs reach a comfortable 21°C (70°F). This is a period of frequent but light rainfall, as the region begins its transition toward the wetter summer months.
Summers are warm and can occasionally feel humid. July is the hottest month, with average highs of 26.6°C (80°F), though modern climate trends frequently push temperatures past 30°C (86°F). This is also the rainiest season; June and July receive the highest amount of precipitation, often delivered in heavy downpours during thunderstorms rather than steady drizzle.
Early autumn, known locally as "Babí léto" (Indian Summer), brings stable, sunny weather and golden foliage. As the season progresses into November, the city experiences a sharp increase in cloud cover and humidity. Winds pick up, and the air begins to carry a damp chill as daytime highs drop toward 5°C (41°F).
Winters are cold and often overcast. While January is the coldest month (averaging around -3°C at night), Brno is significantly drier in winter than in summer. Snow is frequent but rarely deep, often melting within a few days. However, periodic Siberian cold fronts can drop temperatures to -15°C (5°F) or lower, creating a biting, dry cold.
Brno's topography creates several distinct microclimates:
Brno is historically known for its relatively low annual precipitation (around 500-600mm) compared to the rest of the country. A specific phenomenon is the "Föhn-like" effect from the Alps to the south, which can occasionally bring unexpectedly warm, dry winds that clear the winter fog. Historically, the region has recorded extremes ranging from a frigid -25°C in 1942 to a record high of 37.8°C in 2013.
Locals are deeply attuned to the "Wine Calendar" of the surrounding region. The weather isn't just a backdrop; it dictates the harvest and the social life of the city. In the summer heat, the city empties toward the Brno Dam for sailing and swimming. In the winter, the damp cold is countered by the vibrant Christmas markets where the smell of svařák (mulled wine) fills the air, providing a sensory warmth that offsets the frequently gray skies.