Temperatures in Moscow could hit 30 to 31 degrees Celsius on Tuesday, making it the hottest May 14 on record, meteorologists said.
The current record is 28.4 C, set in 1996.
Moscow is in the grips of a scorching spring heat wave. Monday saw near all-time highs, and meteorologists said that Wednesday could break the current record of 27.9 C, Interfax reported.
Weather forecasters say the current hot weather in the capital is uncharacteristic for May, and that the temperature is 8 to 9 degrees higher than normal.
In summer 2010, a severe heat wave gripped much of western Russia sparking wildfires and causing the worst drought in decades as record high temperatures were surpassed more than 20 times over a two-month period.