When warm and humid air rises over a mass of very cold air, it creates unstable atmospheric conditions that can lead to several weather phenomena.

Option 1: Calm weather - This is unlikely to occur in the given scenario. When warm and humid air rises over cold air, it can create a stark temperature contrast, which typically leads to weather disturbances rather than calm conditions.

Option 2: Snowfall - Snowfall can occur when warm and humid air rises over cold air. As the moist air rises, it cools and condenses, forming snowflakes that fall to the ground. Thus, this option is possible.

Option 3: Storms and cyclonic storms - This is the correct option. When warm and humid air rises rapidly over a mass of cold air, it can create strong upward motion and instability in the atmosphere. This instability can lead to the formation of storms, including thunderstorms, squalls, and cyclonic storms.

Option 4: Intense rain and hail - Hail formation usually occurs in severe thunderstorms. These storms are characterized by strong updrafts that carry raindrops upward, where they freeze and accumulate layers of ice before falling as hail. Therefore, this option is also possible.

In summary, when warm and humid air rises