When winter weather forecasts are issued, the term “flurries” is often used, but its precise meaning can be confusing compared to other types of snowfall. Understanding this meteorological term is important because it describes a much less impactful event than a heavy snowstorm. Clarifying the intensity, duration, and atmospheric conditions associated with flurries helps differentiate this common winter precipitation from events that might affect travel or daily plans.
Defining Flurries: Characteristics of Light, Brief Snowfall
A snow flurry is defined by meteorologists as a light, intermittent snowfall of short duration. These precipitation events are typically disorganized and scattered, often lasting only a few minutes at any single location before dissipating. The intensity of the snowfall is minimal.
A defining characteristic of a flurry is its lack of significant accumulation on the ground. Flurries often result in only a trace amount, which is measurable but insufficient to cover surfaces. While the snow may momentarily reduce visibility, it usually does not create hazardous driving conditions. This non-accumulating nature separates a flurry from nearly every other type of winter precipitation.
Distinguishing Flurries from Snow Showers and Steady Snow
The main difference between a flurry and a snow shower is intensity and potential for accumulation. Snow showers are also short-duration events, but they involve a moderate to varying rate of snowfall, often leading to measurable accumulation on the ground. Showers come from more organized precipitation cells and are more vigorous than the sporadic nature of flurries.
Flurries also contrast sharply with steady or general snow, which is associated with large-scale weather systems like widespread low-pressure areas. Steady snow covers a wide geographical area, can last for several hours, and consistently brings significant, measurable accumulation. Steady snow is generated by a major storm system where precipitation is produced over a long period. The difference in impact is substantial, as steady snow requires winter storm warnings, while flurries are a minor forecast detail.
Atmospheric Conditions That Lead to Flurries
Flurries are typically generated by localized atmospheric instability rather than the broad lifting of air masses seen in major winter storms. The formation often requires a cold air mass moving over a relatively warmer surface, such as a large body of water or a localized patch of ground. This temperature difference creates instability in the lowest layer of the atmosphere, causing air to rise in small, convective columns.
As the air rises, it cools and forms small, localized clouds that produce the brief, light bursts of snow. These events are common in areas experiencing lake-effect snow, where cold air moves across unfrozen lakes, picking up moisture and dropping it as flurries or heavier snow showers. The short duration and scattered nature of flurries are due to the isolated and unorganized nature of these small atmospheric columns. Wind often contributes to the sporadic appearance of flurries, as it quickly moves the small precipitation areas across the landscape.