Think of a thick forest; small obstacles (like twigs) stop small, fast-moving insects, but larger, slower objects (like a rolling ball) can pass through with ease. Similarly, atmospheric particles 'block' (scatter) shorter blue wavelengths while letting longer red wavelengths 'roll' through to your eyes.

The scattering of light by atmospheric particles (like dust or smoke) is described by Rayleigh scattering, where intensity of scattering $I \propto \frac{1}{\lambda^4}$. Since red light has the maximum wavelength ($lambda \approx 620-750 \text{ nm}$) among visible colors, its scattering coefficient is the lowest. This allows the signal to penetrate fog, rain, or smoke, ensuring it reaches the human eye with higher intensity compared to other colors.

Always remember that for scattering effects (like the sky being blue or the sun looking red at sunset), the color with the shortest wavelength is scattered most (Violet/Blue), and the color with the longest is scattered least (Red).