The Heights - 7:133
We sent upon them signs such as the flood, locusts, vermin, frogs and blood, but they continued to be arrogant and became a guilty people.
In the context of verses 130, 131...135; disasters as a warning to Pharaoh and his people to take advice and turn away from evil:
The Heights/7:135
And when He delivered them from the calamities for a time, they went back on their promise.
The Ornaments of Gold/43:48
We showed them miracles greater than one and We brought upon them various calamities lest they might turn back.
The Ornaments of Gold/43:49
"O sorcerer, pray to your Lord for us. For you are nearer to Him; we shall come to the way after this"."
The Ornaments of Gold/43:50
But when We removed the calamity from them, they immediately turned back from their words.
The Heights/7:130
And We sentenced the party of Pharaoh to years of drought and famine so that they might be admonished.
The Heights/7:131
"When good came to them, they used to say: "We deserved it", and when evil touched them, they used to accuse Moses and his companions of bad luck. Indeed, their bad luck is decided by Allah. But most of them do not know."
The Heights/7:132
"They said: "No matter how many miracles (signs) you bring to bewitch us, we will not believe you"."
The Heights/7:133
We sent upon them signs such as the flood, locusts, vermin, frogs and blood, but they continued to be arrogant and became a guilty people.
The Heights/7:134
"Whenever a calamity befell them, they said, "O Moses, invoke your Lord for His promise to you. If you deliver us from this calamity, we will believe in you and send the Children of Israel with you."