Which weather effects most commonly degrade radar performance?

• A. Increased radar range due to weather
• B. Attenuation and clutter from rain and fog
• C. Weather improves target discrimination
• D. Weather only affects communications, not radar

Answer: (B)

Weather affects radar mainly through two things: attenuation of the radar signal and clutter from precipitation. Attenuation happens when rain or fog absorbs and scatters the radar energy as it travels, so less energy returns from a target and the overall signal-to-noise ratio drops. This reduces effective range and can hide or weaken real targets, especially with heavier rain or higher-frequency radars where absorption is stronger. Clutter arises because rain and fog themselves reflect energy, creating many echoes on the display that aren’t real targets. This background clutter can obscure targets and make discrimination harder, lowering detection and tracking performance. The other options overstate or misstate the impact—weather doesn’t increase range, it doesn’t improve discrimination, and it certainly affects radar, not just communications.