Opava's winters are long and cold, with temperatures often dropping below -20°C in January and February. March brings a slow warming trend, but April is still quite chilly, with overnight lows around -10°C. Summers are mild to warm, with June and July temperatures rarely exceeding 30°C, while August is slightly cooler. Autumn is characterized by a steady decline in temperature, with October and November seeing overnight lows dip into the single digits. In contrast, winters bring prolonged periods of sub-zero temperatures.