Temperatures reached a record of nearly 30 degrees Celsius on Tuesday, in what was the hottest day of the year so far, and on Wednesday another new record could be set, forecasters said.
Forecasters also warned of intermittent heavy showers and even thunderstorms in parts of the Moscow region, Interfax reported.
The temperature reached a record high of 29.7 C on Tuesday, which is 1.3 C higher than the previous record for May 14, set in 1996, according to the website of the federal weather service.
Tuesday was the fifth day in a row that temperatures exceeded 25 C, and forecasters think that the record high temperature for May 15 could also be broken Wednesday. The previous record of 27.9 C was set in 1946.
The weather bureau said that temperatures have been abnormally high for May, and has also issued a severe weather warning.
"The temperature for May has been 4 C higher than normal, but in the last few days that figure has reached 9 C," the weather bureau said in a statement carried by Interfax.