Neither resort gives out attendance numbers, but Disneyland analyst and author David Koenig said this week could be one for the record books.
"They'll have over 60,000 people today at Disneyland, probably over 25,000 at California Adventure at any one time," he said. "As people leave and come, this week could be close to 100,000 people on property in one day -- a record for Disneyland."
The Happiest Place on Earth sold out Tuesday.
The rebounding economy may be to thank. Some families said they are able to afford a Disney vacation this year.
The Healy's from Salt Lake City are back at Disneyland after a two-year absence.
"We saved up throughout the first of the year, we bought our package in advance, bought our plane tickets in advance and the past two paychecks we put away for this," Shawn Healy said.
Families are also spending the day at Knott's Berry Farm.
In a statement, the park said, "On the days that it did not rain this week, Monday, Tuesday and today, we have seen some of the highest attendance numbers in years for the holiday time period. We anticipate that the weekend will be the same."
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