The "Frozen" star was captured on video performing for those affected by the deadly hurricane inside an Orlando middle school that's been transformed into a shelter.
Bell, 37, shared a photo from her Saturday performance on Twitter.
She captioned it: "When ur #singinginahurricane, ur volunteer back up dancers can(& will) steal the show. Richard & Rebecca everyone!! #HurrcaneIrma #Irma2017."
Meadow Woods Middle School, the location of the shelter, also thanked the actress for entertaining those inside.
"Thank you @IMKristenBell for stopping by today!" the school wrote in one tweet.
"This is the power of being positive and serving others above self!" they added in a separate tweet.
Bell, who portrayed the fearless Anna in the Disney animated film, said on social media that she "didn't have the option to leave" so she decided to hunker down in Orlando, located in Central Florida.
On Friday, she posted a photo of herself on Instagram outside of a grocery store.
The actress also made headlines Saturday for taking in her "Frozen" co-star Josh Gad's "entire family" ahead of Irma's arrival.
"When they were stranded in Florida, she got them a hotel room at her hotel in Orlando and saved them, my brothers, my sister-in-law and niece and nephew," he wrote on Instagram, captioning a pic of Bell with his family members.
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