At what time of day is sporadic-E propagation most likely to occur?

Sporadic-E propagation relies on patches of intense ionization in the E-layer, which is highly dependent on solar ultraviolet radiation combined with the presence of metallic ions from ablated meteors. Because solar radiation is a primary driver for charging these regions, dense E-layer clouds most commonly form and sustain themselves during daylight hours. Consequently, you are most likely to experience Sporadic-E openings between sunrise and sunset. While it is possible for strong Sporadic-E patches to linger into the early evening, daytime is overwhelmingly the most active period. Distractors suggesting nighttime peaks confuse Sporadic-E with standard lower-frequency HF sky-wave propagation, which improves after dark when D-layer absorption disappears.