Los Angeles ? “Signs” ran crop circles around the competition to top an unusually strong weekend box office for August.

The film, starring Mel Gibson as a farmer who finds mysterious patterns marking his fields, raked in $60.3 million, according to studio estimates Sunday.

The top 12 movies grossed an estimated $143 million, down 12 percent from the same weekend last year but still an unexpectedly strong showing, said Paul Dergarabedian, president of box-office tracker Exhibitor Relations.

“All of a sudden comes a month where a $60 million opening is possible. It used to be called the ‘dog days of August.’ It was a slowdown period. Well, this is no slowdown period anymore,” Dergarabedian said.

Three low-budget films opened to modest takes. “The Master of Disguise” eked out third place in a market crowded with family films, taking in $13 million.

In fourth place, “Martin Lawrence Live: Runteldat” opened to $7.5 million. The film follows comedian Lawrence on a 2001 standup tour.

Steven Soderbergh’s “Full Frontal” debuted with just $725,000. The comedy about a group of Los Angeles oddballs had been billed as a return to Soderbergh’s low-budget roots honed more than a decade ago with “sex, lies and videotape.” That film made about $25 million. “Full Frontal” is on track to make just $3 million to $4 million domestically, said David Kaminow, senior vice president of marketing for Miramax.

Next weekend is expected to be a profitable one as well, with the release of Sony Pictures’ “XXX,” a thriller starring Vin Diesel.

Estimated ticket sales for Friday through Sunday at North American theaters, according to Exhibitor Relations Co. Inc.:

1. “Signs,” $60.3 million.

2. “Austin Powers in Goldmember,” $32.4 million.

3. “The Master of Disguise,” $13 million.

4. “Martin Lawrence Live: Runteldat,” $7.5 million.

5. “Road to Perdition,” $6.6 million.

6. “Stuart Little 2,” $6 million.

7. “Men in Black 2,” $4.7 million.

8. “My Big Fat Greek Wedding,” $3.01 million.

9 (tie). “K-19: The Widowmaker,” $3 million.

9 (tie). “The Country Bears,” $3 million.