Why should more time be allowed for taking observations at night?

When taking weather observations at night, allowing more time for the process is crucial primarily because your eyes need to adjust to darkness. This adjustment period is essential for accurately assessing visual conditions. The human eye takes time to adapt to lower light levels, which affects the ability to see and interpret various weather phenomena, such as cloud cover, precipitation, and atmospheric visibility.

Observing at night often entails relying more on visual assessments due to the absence of ambient light, making it difficult to discern details immediately. Thus, a period for adjustment aids in gathering more accurate and reliable observations.

Although there are elements of complexity involved when observing at night, such as the variability of nighttime atmospheric conditions, the need to allow your eyes to adapt to darkness remains the most critical reason for taking additional time with observations after the sun sets.