There are many different ways in which weather-related phenomenon cause fires.
Burning lava from volcanoes sets towns aflame. Fires can be the most destructive part of earthquakes, though they only happen when earthquakes occur in populated areas.
Earthquakes rupture gas lines and electrical wires, as was the case in the great San Francisco earthquake of 1906. Three-quarters of the city burned down.
Lightning bolts striking the planet can easily spark a fire, especially during a dry spell or a drought.
The wind not only fans fire, but can sometimes cause it. Two tree branches violently rubbing against each other during a drought can create enough friction to make sparks and the sparks can develop into flames.
Over 50 percent of the massive fires that occur in the western United States are caused by lightning.