Which significant weather event occurred in California during 1997, leading to extensive flooding?

The significant weather event that occurred in California during 1997, leading to extensive flooding, was indeed related to New Year's storms. These storms occurred at the turn of the year and brought significant rainfall, resulting in severe flooding in various parts of the state. The heavy precipitation overwhelmed rivers and drainage systems, leading to widespread damage and hazardous conditions.

While El Niño storms are also associated with heavy rainfall in California, it was the specific series of storms around New Year's that peaked in intensity and caused significant flooding during that period. Santa Ana winds are known for their dry and warm conditions, facilitating fire hazards rather than flooding, and wildfire season refers to a time of year characterized by heightened wildfire risk, which is not directly related to flooding events. Thus, the impact of the New Year's storms is the defining event linked with extensive flooding in California during 1997.