Boys cool off at a fountain in the Ural Mountains city of Yekaterinburg, east of Moscow, on Thursday. (Alexander Zemlianichenko/Associated Press)

The worst heat wave since the Stalin era has thrown Russia into turmoil, with droughts devastating millions of hectares of crops and a state of emergency declared in 19 regions.

Temperatures on Friday were expected to reach 33 degrees Celsius, and the state weather bureau in Moscow said it expected the heat wave to continue into next week. Saturday could see temperatures in Moscow hit 37 C, which would break the previous high of 36.6 C set in 1936.

"It looks like tomorrow could just break the record," the weather bureau's Moscow head, Yelena Timakina, said. No rain is expected in the next several days.

Many Russians have turned to swimming in lakes and rivers to cool off, but a lack of lifeguard supervision combined with alcohol use has prompted a rash of drowning accidents. The Emergency Ministry reported there were more than 1,200 drowning accidents in June, and at least 400 more have drowned since the beginning of July.

Crop crisis

An estimated 10 million hectares of crops, or 12 per cent of all cultivated land in Russia, has been destroyed by the hot, dry weather, and forest fires have encircled Moscow in a ring of smoke.

The government may lower its forecast for this year's grain harvest again, Agriculture Minister Yelena Skrynnik said earlier this week, to below 85 million tonnes from the original target of 97 million tonnes.