Why does the relative humidity drop so low a few weeks every year mid-April? This happens across the country!?

Question

Low relative humidity. Fall in relative humidity. Early spring humidity. Dryness spring air.

Answer 1

It is a known fact that when temperature increases over a place ,the relative humidity falls provided no moisture is added.In April(after March 21) the sun enters the northern hemisphere from the southern hemisphere(in its apparent movement towards north) and the temperature increases in all places in the northern hemisphere.Hence the relative humidity drops in most of the interior places.This is a temporary phenomena.

Subsequently,more evaporation takes place over all the water surfaces in the northern hemisphere due to increase in temperature , and the relative humidity in the air gradually increases subsequently.