Cable channels are already making upfront presentations to advertisers, and those sales efforts will accelerate on Thursday when Discovery Communications introduces its fall shows. According to new forecasts out this week which do not take into account the deepening NFL labor strife, cable channel sales could hit $9 billion during the coming 2011 upfronts, up 11.5% over last year. As for broadcast, Miller Tabak analyst David Joyce projects a 14.9% increase to nearly $9.9 billion for the Big Four networks’ primetime schedule unveiling next month. Media services firm Zenith Optimedia also said this week that it expects double-digit gains in cable and broadcast sales. Car, cell phone, and banking service companies — eager to take advantage of the thawing economy — could make this upfront ad-sales season one of the strongest since 2003. Auto companies normally account for about a quarter of TV ad sales but were in a deep slump during the economic crisis giving the TV honchos fits. Now they’ll likely drive the market once more. They’re introducing 65 new models this year vs. 60 in 2010, and only 40 in 2009.

There’s one potential cloud in the sunny forecasts: Networks, especially NBC and ESPN, will struggle to find attractive programming to replace NFL football if the contract dispute between owners and players forces the league to cancel the 2011-2012 season.  Advertisers spend about $3 billion a year to sell their wares on televised football games.

Remember, networks for years have sold as much as 80% of their ad inventory in the upfront market in a sales frenzy that typically takes place in May and June right up to July 4th. The last two years, however, much more emphasis was put on the scatter market as big advertisers worried about making sizeable commitments in the economic doldrums.