Isn't it meaningless? Sentence marked in Bold

Sanjay, let's pick the paragraph apart. It reads like a transcript of a podcast, and so, it contains many of the redundancies and wordy phrase common in speech. We will correct it for z better written form.

"Now" is unnecessary, as is "in the recording".  We could easily start with "In the background, you can hear."

"the sound of rain" --> "sound" is unnecessary because we are told we can hear it --> "you can hear rain."

We need to add a comma after Hawaii. Otherwise, the sentence is a run-on.

"and it is raining" is redundant, but I believe it is necessary to convey the writer's meaning. Let's leave it.

"outside" --> The writer has problems because she is sitting inside the porch (or under the porch's roof) which is outside of the house, but not really outside in the rain.  As you can see, this not really outside but not really inside condition is hard to describe. Perhaps "I'm sitting on a porch on the Island of Maui, and it's raining 0utside." Notice that a comma must be added  after Maui to correct the run-on sentence.

"In the background, you can hear rain because today I am in Hawaii, and it is raining. I'm sitting on a porch on the island of Maui, and it's raining outside. It’s beautiful.  There are green tropical trees and bushes all around. It’s a nice setting to talk to you today."

Notice the added commas and capitalization.  

It's redundant.  It's raining was stated in the previous sentence.  Is this your writing, Sanjay? Or is it something you're reading and that part jumped out at you? I ask because I have some suggestions for the rest of the paragraph, but I don't know if it's yours.