There is a similarity between farmers and some HVAC companies. For many companies, their entire success is predicated on having a successful summer. If your business is dependent on the summer, there are methods to becoming a weather-enhanced business rather than a weather-dependent business. Until you've mastered those systems, however, you'd better become a master at harvesting your revenue in the summer.
Many contractors who are dependent on the summer months will find they don't have the manpower necessary to handle the demand.