Abate

abate
verb, intransitive. Of something perceived as hostile, threatening, or negative, to become less intense or widespread.
verb, transitive. To cause to become smaller or less intense. To lessen, reduce, or remove,  especially in reference to a nuisance.

Even though they had never been through one before, the roar of an approaching tornado was unmistakable. They had been watching television, regular programming pre-empted by alarming weather reports, when the power went off and they heard the noise. Their eyes met in the storm-dimmed light of late afternoon.

"Sounds as if we got the cellar built in the nick of time," she remarked. "We'd better go use it."

Uncharacteristically, he said nothing--only nodded.

They paused only to grab what each considered the most important things: his wallet and metal detector; her purse and laptop; then hurried outside. The wind was strong in the eastern lee of the house. Outside that shelter, it was difficult to walk upright. Fortunately, it was only ten yards from the house to the storm cellar entrance. He opened the sturdy door and they entered the stillness within gratefully and descended the steps.

Inside, several feet of earth muffled the sound of the approaching twister. She elbowed the switch to turn on the battery-powered light, then put her burdens down. She turned to her husband. "I hope it doesn't take the house. Just the thought of having to replace all our stuff makes me ill."

He put his arms around her. "If it happens, it happens. That's why we have insurance. We'll still be alive." She nodded.

They stood, embracing, and listened to the muted sound of the wind. In a very short time--ten minutes, perhaps--it abated. They dropped their arms and searched each other's faces.

"Time to look," she said.

He went first. As she was about to mount the steps, she turned and looked at the little room where they had hidden from the storm's fury. Her father had badgered her until she got the loan and had this cellar built. Now, as she had so many times in her life, she was glad she had listened to him. Today, his advice might have saved their lives.

Definitions adapted from The New Oxford American Dictionary, Oxford University Press, Inc., 2005 (eBook Edition, copyright 2008), and from Webster's Seventh New Collegiate Dictionary, G. & C. Merriam Company, Publishers, Springfield, Massachusetts, USA, 1965, depending on which is more convenient to hand.