They drive for hours without a break, ignore weather reports and go swimming in dangerous conditions: Czech holidaymakers have provoked official warnings that their undisciplined behavior has put their own lives at risk.

Though northern and Central Europeans in general are often the butt of jokes for their holiday excesses — from baking in the sun to drinking like fish late into the night — the deaths of 15 Czechs in Croatia this summer have prompted a series of official caveats. The Croatian Interior Ministry has asked hoteliers and tourism providers to explain to Czechs the dangers they face when they abandon their landlocked homeland in search of the pleasures of the Adriatic coast.

The Czech Foreign Affairs Ministry issued a statement Aug. 10 advising citizens to follow local weather forecasts carefully, adding that several tragedies resulted from underestimating dangerous conditions, in particular the strong offshore wind known as the bura.

One million tourists from the Czech Republic are expected to visit Croatia this year — more than from any other country. Likewise, more Czechs have lost their lives there than any other nationality, according to Croatian press reports.

One recent casualty: a 16-year-old boy killed by lightning near the central coastal town of Zadar when he set sail in a storm.

"Some of our tourists really are undisciplined and underestimate the forces of nature," said Veronika Honcová, the Czech consul in the Croatian capital, Zagreb.

"For example, two tourists went swimming, although they knew very well that the dangerous wind, the bura, was blowing," Honcová said. "After four hours, they were rescued by the Croatian coastguard, far away from the shore and totally exhausted."

But sometimes the danger results from more than just unknown local conditions; sometimes, tourists themselves create the danger.

"Czechs belong among those tourists who take the most risks while vacationing in Croatia," said Matyás Zrno, a journalist for Czech Television who spent several weeks this summer reporting on his countrymen's activities on the Adriatic. According to Zrno, holidaymakers make unwise decisions even before arriving at the coast.

"Our tourists often travel nonstop to reach the sea as soon as possible," he said. "The result of this approach is that they very often cause a car accident just a few kilometers before they reach their destination."

Meanwhile, many remain unaware that water can distort a person's sense of distance, Zrno continued. In July, for example, a Czech family decided to swim from the town of Makarska to the island of Brac, south of Split.

"They had no idea that it is 15 kilometers away. They were rescued, completely exhausted, several kilometers from the shore," Zrno said.

Last year, 19 Czechs died in Croatia. With a tourist season that lasts at least until mid-September, the death toll this year could easily surpass that.

Honcová said Czech authorities do all they can to provide tourists with safety information, including broadcasts on a seasonal Czech radio station in Split with a signal that reaches across central Dalmatia.

Next year the station will also broadcast from the southern city of Dubrovnik and the northern town of Rijeka, Honcová added, providing Czech-language coverage along the entire Croatian coast in the summer.

As in 2004, Croatia remains the favorite summer holiday location for Czechs this year. Relatively close by car, the languages of the two countries are related and the Adriatic coast has been a traditional holiday destination for Czechs for a century.

Meanwhile, Croats remain friendly toward Czechs, even if they still sometimes refer to them as pastetari or paté eaters, according to Zrno.

The phrase, he explained, comes from the perception that the typical, thrifty Czech tourist brings his own food and eats just bread and paté, rather than spending money in restaurants.