The UK box office was hit over the weekend by a heatwave which saw the country record its hottest ever temperature on Sunday.

Many films saw their earnings drop substantially week-on-week, including last week's leader Terminator 3: Rise Of The Machines, which fell 55%.

Total box office was notably 13% down week-on-week and 7% down against the same weekend last year.

The leader at this weekend's box office, BVI's Pirates Of The Caribbean: The Curse Of The Black Pearl, still took a healthy $6.1m (£3.8m) from 452 sites, including $891,053 (£553,344) on Thursday - its official opening day - from 379 sites. While a strong result, the well-reviewed action adventure may well have performed better had the climate been cooler.

However, the extreme heat of Sunday may in fact have driven audiences to seek out the air-conditioning of cinemas. Bizarrely, Sunday was the highest earning day of the weekend with $5.2m (£3.2m) taken across the country compared to Friday's $4.4m (£2.7m) and Saturday's $4.9m (£3m). Sunday was also Pirates' highest earning day of the weekend.

One explanation of the Sunday rise may have been the addition of UIP's American Pie: The Wedding which previewed that day only (see separate ScreenDaily.com story) to good numbers - suggesting whatever the weather UIP can expect a hit with the comedy next weekend.

Sunday was 17% up on the same day last weekend (Aug 3) and 12% up on the equivalent Sunday last year (Aug 11, 2002).