The next time it will happen is July 2011. It happens once or twice a year.
Does a month having 5 Fridays, 5 Saturdays and 5 Sundays only happen once every 823 years?
No.
A year can only start on one of seven days, so there are seven possible basic calendar years. Add leap years, and there are fourteen basic calendars. Period. And one of those calendars only gets used every 823 years? How would that be possible? It's not of course, all fourteen calendars get cycled through regularly, in fact 2010 uses the exact same calendar as 1999. That's eleven years, not 823.
The next time is March of 2013
every 5 years
Once every 11 years.
Usually 5.
once to twice per year
twice a month. Usually on the weekends
10 years
A 31 days month starting on a Friday.
between 5-10 years. The next years we will have 5 weekends in July are 2011, 2016, 2022, & 2033.
At least 4 and sometimes 5, depending on the year.
Any month with 30 or 31 days can have 5 weekends (Sat-Sun) if it starts on a Saturday - for 30 day months - or a Friday or Saturday - for 31 day months. Months with only 4 weekends are any February, or any month that does not start on a Friday or Saturday. A non-leap year calendar year will have either 52 or 53 weekends, and will have either 2 or 3 months with 5-day weekends.
1999 I think it was 2009 since there were 5 Saturdays in that month October.
is there any month with 5 weeks in it