What is indicated by the code BLSN?

The code BLSN indicates "Blowing Snow." This term is used in meteorological observations to describe a phenomenon where snow is lifted and blown by the wind, reducing visibility and creating hazardous conditions. Blowing snow typically occurs when loose, powdery snow is present and winds are strong enough to transport it. The visibility can be significantly impacted, sometimes dropping to less than a quarter mile, which is critical for weather reporting and aviation safety.

In contrast, blizzard conditions would require specific criteria including extreme wind speeds combined with significant snowfall, which would not be solely represented by the abbreviation BLSN. Snow flurries refer to light snow that falls intermittently and doesn’t accumulate heavily, while light snow generally signifies a steady, low-intensity snowfall. Therefore, the designation of "BLSN" is distinct and specifically used for situations involving blowing snow.