The UK's biggest commercial broadcaster, ITV, is expecting a stormy summer as its July ad sales are predicted to slip even lower than the forecast 4% slide.

Media agencies report that revenues for July are expected to be around £260 million ($489.9m; €381.7m), lower than the £275m predicted, and down as much as 8% year-on-year.

These gloomy figures come on top of an expected 3% year-on-year sales drop for June, despite the apparent lure for advertisers of the soccer World Cup tournament.

ITV's sneeze could mean the rest of the UK advertising industry catching a cold and the broadcaster may now have to wait until September or October at the earliest to see any uplift in revenues.

Rival Channel 4, which is state-owned but commercially funded, is pinning its advertising hopes on its reality TV hit Big Brother, now in its seventh year.

Media owners and agencies have tended to optimize ad revenue expectations in years with major sporting events. Figures also show that this year money is being siphoned into online advertising while most other media - radio, outdoor, print - are volatile.

Comments Chris Hayward, head of broadcast at ZenithOptimedia: "In reality, the TV market has been sluggish for the last 14 months and some advertiser categories such as retail and fmcg supporting sectors like cars and alcohol have been sluggish."

But he adds: "The state of revenues is not indicative of channel audience performance overall. July is a weaker revenue and programming month overall anyway so it is too early for alarm bells."

Data sourced from; additional content by WARC staff