It appears that many individuals are currently experiencing issues with iCloud, with several people reporting difficulties receiving/sending iCloud mail and logging into iCloud.com. Users attempting to access iCloud.com are receiving the following error message: "iCloud encountered an error while trying to connect to the server."
Update 12:30 PM PT: According to Apple's System Status page, the issues with iCloud have been resolved.
Article Link: iCloud Services Currently Down for Some Users [Update: Fixed]