The Disneyland Resort just announced that Disneyland Park and Disney California Adventure will not reopen on July 17th as anticipated. The reopening of Disney's Grand Californian Hotel & Spa and Disney's Paradise Pier Hotel will also be delayed. Downtown Disney will still open on July 9th.
The state of California has not issued theme park guidelines, and is not expected to until at least July 4th. The resort says that, with the short notice, they would not have enough time to bring back Cast Members and restart their business.
Once guidelines are in place, new opening dates will be announced.
Here is the full text of the announcement: