If necessary to connect to the cloud periodically to ensure that your account is paid current. What is it that you expect to accomplish by installing Lightroom CC without the cloud? I don't understand why you would want to do that. You would not be able to use Lightroom Mobile. Is there something about the cloud that concerns you?
There is no Cloud. LR CC is installed on your hard drive. The only reason you ever have to connect to the internet is to verify your subscription is paid up and active. That only needs to happen every 90 days.
Expanding on Jim's post...
You need an active internet connection every 30 days or so to confirm the active license/subscription.
It is completely optional to send any images to "the cloud", meaning any of Adobe's servers where you can share your images with your mobile devices and/or other people. By default this sharing does not happen.
All the software is installed on your hard drive. All your original images remain on your hard drive(s).
Instead of a monthly subscription, you can subscribe annually, which allows you to be offline for much longer (not sure of actual time). You can disable the CC Desktop app in your Startup folder (use Msconfig or similar)