Why Precipitation only scatters or absorbs radio energy when the raindrops are a significant fraction of a wavelength, which happens at microwave frequencies (roughly 10 GHz and above). At 28 MHz and 50 MHz the wavelength is measured in meters, so raindrops and fog droplets are millions of times smaller and essentially invisible to the wave. That is why weather-related rain scatter and rain fade are microwave concerns, not 10-meter or 6-meter concerns.
Watch out Absorption is the tempting pick because it is real, but it applies to microwave bands and to the ionospheric D layer, not to raindrops affecting HF and low VHF.
Raindrops are millimeters; 10 m and 6 m waves are meters. Too big to notice the drops.