gowthami,
"Ought to be" when referring to present or future probability means that something is
PROBABLY TRUE.
Do we have any milk?
Ans: There ought to be some in the refrigerator. = There is probably some in the refrigerator. or There should be some in the refrigerator.
The first half of the football game was boring, but the second half ought to be good.
......the second half will probably be good. or ....the second half should be good.
That ought to be good for a few laughs. = That is probably good enough to cause a few laughs.