Can the Moon be Wet or Dry?
Last week someone inquired on our forum about a “wet or dry moon.” We did a little digging and thanks to our astronomer, Joe Rao, here is what we found out about a dry or wet moon.
In the evenings during the spring (March, April, May) and in the mornings during the fall (September, October, November), the crescent Moon will be oriented in such a manner so as to resemble a “thin smile” or “boat” with the cusps or horns of the crescent pointed straight up. This is the so-called “wet moon” because it seemed that the Moon was holding water.
In contrast, in the evenings during the fall and in the mornings during the spring, the crescent Moon is turned roughly 90-degrees; that is sideways, giving the impression that if there was any water being held within the crescent that it would appear to spill out. This is the so-called “dry moon.”
There is no real meteorological connection to any of this. The reason the crescent Moon changes its orientation is because of the orientation of a line on the sky called the ecliptic. When the ecliptic is nearly perpendicular (straight up and down) relative to the horizon, we get the wet moon. When the ecliptic has a large slant/slope relative to the horizon, we get a dry moon. But any association with the Moon’s orientation and any spell of dry or wet weather is purely folklore.