Some people may have difficulty grabbing a hold of the idea that "Judgment Day" is in actuality a time period longer than a single day.
However, keep in mind that God uses various time language in the Bible and constantly has periods of time represent other longer periods of time. For example:
about ½ hour (Rev. 8:1) = 2300 evening mornings (first part of the Great Tribulation period)
1 hour (Matthew 20:9-12) = 23 year Great Tribulation period
The day God created the world (Gen. 2:4) = 6 days
The Day of Salvation = at least from 33 AD until May 21, 2011 AD (1,978 years)
Day of Temptation in the Wilderness (Heb. 4:8,9) = 40 years
3½ days (Rev. 11:9-11) = 2300 evening mornings/first part Great Tribulation
1,260 days (Rev. 12:6) = entire N.T. Church Age of 1955 years
1,000 years (Revelation 20:1-4) = 1955 years of the Church Age/ 33 AD to 1988 AD
This is only a partial list. In fact, it is rare when God gives a literal time period in the Bible. Previously, we thought that the Day of Judgment would be a prolonged time period of 5 months. Although we were wrong about the duration we were correct in understanding that Judgment Day is a period of time much longer than an actual day.
Presently, Biblical evidence points to a 23 year (inclusive) long extended Judgment Day period.