Counties with major parks have seen dramatic increases in COVID-19 hospitalizations since early November.
The limited-capacity event will feature seasonal food as well as some family rides and at least one roller coaster.
Mayors of Los Angeles and San Diego were among those supporting a Tier 3 reopening for California's theme parks.
Disney World entrance signs are getting a slight makeover to match the new Cinderella Castle color palette.
The limited reopening will not include any rides or attractions due to California's current COVID-19 rules.
The email came more than a month before the first Orange County inspection of Fun Spot's Orlando location.
Theme park presidents used words like "arbitrary" and "unachievable" to describe California's guidelines that would allow parks to reopen amid the COVID-19 pandemic.
The release comes after a month of verbal sparring between Disney, the theme park industry and Gov. Gavin Newsom.