The Games soared into high gear on Monday, featuring 19 gold medals up for grabs, including five in swimming.

With temperatures expected to reach 30 degrees Celsius (86 degrees Fahrenheit) and clear skies, the aftermath of Friday’s and Saturday’s heavy rains leaves Tuesday’s triathlon in the Seine in uncertain territory.

Here’s everything you need to know about Monday’s Olympic action.

Muddy waters

Paris Olympics organizers canceled the triathlon swimming training session for the second day in a row on Monday, with 24 hours to go until the men's race, after heavy rain affected water quality levels in the Seine.

France has invested about $1.4 billion in new wastewater infrastructure to reduce sewage flowing into the river, and city authorities have announced plans to open three swimming sites to the public by June next year.

No 'three-peat'

Italy's Nicolo Martinenghi won the men's 100-meter breaststroke gold on Sunday, ending Adam Peaty's bid for a "three-peat" in the same event at three successive Games.

Peaty, hoping to become only the second male swimmer after retired U.S. great Michael Phelps to achieve the triple, had to settle for silver alongside reigning world champion Nic Fink of the United States.

Japan on top for now

Japan is leading the medal table after two days of action, with wins in judo, skateboarding, and fencing.

France has given the home crowds plenty to cheer about with two more golds on Sunday.

Pauline Ferrand-Prevot dominated a high-quality field to win the women’s cross-country mountain bike race.

World record holder Leon Marchand then won the 400-meter individual medley in emphatic style, sending fans into delirium at La Defense Arena.

Far-left extremists in frame for rail sabotage

France is leaning toward the likelihood that far-left extremists were behind last week’s sabotage of the country’s SNCF rail network, which coincided with the Olympic Games opening ceremony, Interior Minister Gerald Darmanin said.

Saboteurs attacked France’s high-speed train network on Friday with pre-dawn strikes on signal substations and cables at critical points, causing travel chaos hours before the opening ceremony.

Israeli death threat probe

French police have opened an investigation into death threats against three Israeli athletes at the Games, the Paris prosecutor’s office said on Sunday.

Anti-cybercrime officers are also investigating the release of athletes’ personal data on social networks on Friday and are working to have it removed, prosecutors said.