Moses and Aaron walked out of the palace, past the gates, into the suburb of the city. And there, in the open, Moses did exactly what he had promised.
The Targum Pseudo-Jonathan on Exodus 9:33 records it: "Mosheh and Aharon went out from Pharoh to the suburb, and he stretched out his hands in prayer before the Lord, and the thunders of the curse were withheld, and the hail and rain that were descending came not on the earth."
The Aramaic paraphrase, preserved in the Targum long attributed to Yonatan ben Uzziel, uses the phrase ra'amei la'ta — again, the thunders of the curse. Not simply noise. Verdicts. And when Moses spread his palms, the verdicts were itk'lu — held back, withheld, paused.
The Targum even notes a miracle within the miracle: the hail and rain that were already mid-fall did not reach the earth. Hailstones suspended in midair. Raindrops stopped in their descent. The storm was not merely shut off at the source. It was frozen wherever it was.
The Maggid teaches: when the Holy One answers the prayer of a righteous person, He does not only change what is about to happen. He sometimes rewrites what is already happening. Moses's open hands were enough to catch a storm in mid-fall.