Iced Coffee and Flip-Flops as Europe Broils? Not So Fast, Americans.

On a scorching June day on the Amalfi Coast of Italy, Chloe Madison and her boyfriend, Colin Pinello, stopped to have lunch in Positano, a glamorous town overlooking the Mediterranean Sea.

With their refreshing caprese pasta plates and Aperol spritzes, they had one thought on their minds: ice water. But they knew that asking for it would be too American. While the Europeans around them seemed unfazed by the temperatures, she said, they felt parched.

“Water was something we consistently had to request,” she said, and when they asked for ice it was “just a few cubes.”

Ms. Madison, 27, decided to poke fun at this, posting a TikTok video of the couple fanning themselves with the caption: “fighting the American urge to ask for a cup of ice water in Europe.” (In this, she joined a trend of Americans wanting frosty drinks in tourist hot spots, with some musing on social media if Europeans simply don’t drink water.)

With U.S. tourists returning in high numbers to Europe this summer and heat waves also setting records, American sensibilities about staying cool are butting up against European etiquette and norms. (Some tourists are changing their travel plans because of the heat.) Amid the broader climate change crisis, a penchant for flip-flops, shorts and guzzling ice water may seem trivial, but those differences can be stark.

Savvy travelers seeking to blend in with the locals have increasingly turned to social media, particularly TikTok, for advice and commiseration. Much of the guidance will sound familiar to seasoned travelers.

For example, be careful about small talk and asking personal questions of strangers. Don’t be surprised that many Europeans still smoke in cafes and other public places. Do a little research about local customs and learn some basic conversational phrases in the local language.

There’s also this standard advice for Americans: “Be less loud.”

But the record high temperatures in Europe have led to a new theme in online travel advice.

“I couldn’t help but notice the striking contrast between how Americans and Europeans handle a heat wave,” Ms. Madison observed, saying that Europeans “didn’t appear to rely as heavily on things Americans consider essential.”

The experts agree. For a start, don’t expect a big water pitcher filled with ice cubes the moment you sit down in a restaurant.

“It’s not common at all in Europe,” said Viviane Neri, director of the Institut Villa Pierrefeu, a finishing school in…