וַיֵּ֨ט מֹשֶׁ֣ה אֶת־מַטֵּהוּ֮ עַל־הַשָּׁמַיִם֒ וַֽיהוָ֗ה נָתַ֤ן קֹלֹת֙ וּבָרָ֔ד וַתִּ֥הֲלַךְ אֵ֖שׁ אָ֑רְצָה וַיַּמְטֵ֧ר יְהוָ֛ה בָּרָ֖ד עַל־אֶ֥רֶץ מִצְרָֽיִם׃
And Moses stretched forth his rod toward heaven; and the LORD sent thunder and hail, and fire ran down unto the earth; and the LORD caused to hail upon the land of Egypt.
Read kabbalistic (mystical) interpretation of Exodus 9:23: and classical mystical sources.