The average annual rainfall in Orlando is , a majority of which occurs in the period from June to September. October through May are Orlando's dry season. During this period (especially in its later months), often a wildfire hazard exists. During some years, fires have been severe. In 1998, a strong El Niño caused an unusually wet January and February, followed by drought throughout the spring and early summer, causing a record wildfire season that created numerous air-quality alerts in Orlando and severely affected normal daily life, including the postponement of that year's Pepsi 400 NASCAR race in nearby Daytona Beach.