What is represented by the code BLSA?

The code BLSA represents "Blowing Sand." In aviation meteorology, specific codes are used to communicate important weather phenomena in a concise manner. The "BL" prefix indicates that the condition is occurring near the surface, affecting visibility and potentially impacting flight operations.

In this case, BLSA signifies that there are particles of sand being lifted and blown by the wind, which can create reduced visibility conditions. This is particularly important for pilots to understand, as blowing sand can pose hazards during takeoff and landing phases due to its potential to obscure visibility and create turbulence.

Other options, while relevant to meteorological observations, do not accurately match the code BLSA. For instance, blowing spray pertains to moisture from water surfaces, partial fog refers to reduced visibility from low-lying clouds or fog, and moderate ice pellet showers describe a form of winter precipitation. Each of these phenomena is represented by different codes in weather observations, hence they are not applicable to BLSA.