What does BLPY refer to on a METAR?

• A. Blowing Spray
• B. Blowing Snow
• C. Blowing Dust
• D. Blowing Fog

Answer: (B)

In METAR present weather, a blowing condition is indicated by the BL prefix, which signals wind-driven particles or moisture. The two-letter suffix then identifies what is being blown. Here, the suffix corresponds to snow, so the combined code denotes wind-driven or blowing snow. That makes blowing snow the phenomenon described by this code, which directly affects visibility and can create drifting and difficult braking on runways—both critical factors for flight operations. Blowing dust would be shown with a different suffix (dust), and fog or mist have their own distinct codes, not represented by this BLPY form.