Cal. fire officials say three of the fires were sparked by dry lightning.

加州消防局官员表示，其中三起火灾由无雨闪电引发。

Dry lightning streaked a dark corner to the south—sign that a storm had built up its static charge there.

干燥的闪电划过南边一个黑暗的角落——表明风暴已经在那里积聚了静电。