Improved Alternative: ----- The weather has been really hot lately. Japanese summers are hot and humid, which makes things feel quite uncomfortable.----- Tip -- • “It is hot these days” is understandable but sounds more natural as “It’s hot these days” or “The weather has been really hot lately.” -- • “Summer is humid heat in Japan” is not correct word order. Native speakers say “hot and humid” to describe this kind of weather. -- • “Painful” is too strong here unless you mean physical suffering. “Uncomfortable” is more natural and accurate for describing sticky or sweaty summer weather. --