Due to multiple factors, expect to potentially pay more when booking in November. For low rates, June can be a great choice for travel to Ocean City. Flights to Ocean City from Chicago O'Hare Intl Airport in June are about $419 on average during June, but can be found for as low as $225.
Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Chicago O'Hare Intl Airport to Ocean City as you normally would.