Conclusory.
Lack of rain is the primary culprit as super dry conditions create tinder across vast stretches of forests and grasslands which are so prevalent across the American West. Rainfall this year in the West is at 30% of annual levels. In those conditions, any “spark” can start a raging fire, eg a car bumper scraping on the pavement, an untended camping fire, a thrown cigarette, dry lightning, a downed powerline, etc. If a new fire is fueled by high, dry winds, the firefighters have no hope of putting it out or even containing it. The fire quickly consumes all fuel (dry grasslands, dry trees) in its path.
Populated areas built near grasslands and dry forests are easy targets. Firefighters clear “firebreaks” to protect homes. These won’t stop the fires but perhaps will steer them towards less populated areas.