This ScienceBrief Review on the link between climate change and wildfire risk, focusses on articles relevant to the wildfires ongoing in the western United States (September 2020), new findings relevant to the wildfires that raged southeastern Australian during the 2019-2020 fire season, and new findings since January 2020. New scientific publications reviewed since January 2020 strengthen the evidence that climate change increases the frequency and/or severity of fire weather – periods with a high fire risk due to a combination of high temperatures, low humidity, low rainfall and often high winds – in many regions around the world. The western United States is among the regions where the trends in fire weather have been most pronounced in the past at least 40 years. Fire activity is influenced by a range of other factors including land management practices. However, land management alone cannot explain recent increases in wildfire extent and intensity in the western US or southeast Australia because increased fire weather amplifies fire risk where fuels remain available.