Hot network upfront rotten for local: weak economies translate into weak TV-station advertising sales.(TV Buyer)(a ranking of the top advertisers on local television stations)(Illustration)

Local TV stations are continuing to choke on the dust left by their national network parents, with most affiliates struggling to squeeze out even tiny bits of growth for the rest of the year.

The weak economy continues to overwhelm local markets. Analysts and station group executives say that, while network owned-and-operated stations should do better, affiliate station groups are expecting 2%-4% sales increases for the fall and the holiday rush.

And that's after adjusting for political advertising, which surges when many congressional, state and local terms expire during even-numbered years but disappears in years like this one. Without adjusting, ad sales for most stations would be down sharply.

The sales picture should become a little clearer this Thursday during the Television Bureau of Advertising's annual advertising forecast conference in New York, which will focus on local …