Dozens die in Japan's record heat wave, UK has hottest day of the year Japan's heat wave has killed more than 40 people this month.

LONDON -- It's the hottest day of the year so far in the U.K. and Brits are melting. At 92 degrees in parts of England, it's even hotter than Miami and Tel Aviv today.

But in Japan, the situation is even worse. Temperatures hit 106 degrees today, smashing the national record and continuing a deadly heat wave in which dozens have already died in Japan since July 9, according to Kyodo News.

In the U.K., the Met Office has issued a level three amber alert, warning people to stay out of the sun this week, particularly during the hottest hours of the day.

The Met Office alert lasts until 9 a.m. on Friday morning. The agency published guidelines on how to prevent overheating:

"Stay out of the sun. Keep your home as cool as possible –- shading windows and shutting them during the day may help. Open them when it is cooler at night. Keep drinking fluids."

The heat wave, which has included the U.K.'s highest temperatures in 50 years, has also extended through northern Europe.

Blistering temperatures and an ongoing drought has turned fields dry and brown from Poland and Latvia to Finland and Sweden.

Many European farmers are dipping into their winter food supplies already. They have also warned that crop yields and milk quality will be lower due to the lower quality of the grass.

In Sweden, temperatures have been the highest in a century, spurring dozens of wildfires, some even inside the Arctic Circle. An international team of firefighters has come together the fight the blazes.