TSK · Isaiah 55:10

So David asked the LORD once again. But again the LORD replied,“Arise, go down to Keilah, for I will give the Philistines into your hand.”

He will descend like rain on the mown grass, like showers that drench the earth.

I will make it a wasteland; no one will prune its vines or hoe its ground, and thorns and briers will grow there. I will order the clouds not to drop any rain on it.

For just as the ground produces its crops and a garden yields its produce, so the Sovereign LORD will cause deliverance to grow, and give his people reason to praise him in the sight of all the nations.

Sow righteousness for yourselves, reap unfailing love. Break up the unplowed ground for yourselves, for it is time to seek the LORD, until he comes and showers deliverance on you.

These two have the power to close up the sky so that it does not rain during the time they are prophesying. They have power to turn the waters to blood and to strike the earth with every kind of plague whenever they want.