While the cloud generally is secure, it has weak spots, too.
One vulnerable area: migrating data.
This means you must be extra cautious when moving data to and from the cloud. Be vigilant when selecting your network connections; make sure that all parties use proper tools to maintain security.
The cloud is still relatively new, but more and more organizations are becoming proficient in security.
One smart step is to emphasize security even before the data is moved to the cloud. This will reduce flaws and increase consistency.