Hurricane Heather was one of the worst tropical cyclones to affect Arizona on record. The sixteenth tropical cyclone, eighth named storm, and fourth hurricane of the 1977 Pacific hurricane season, it began as a tropical disturbance on October 3, before later developing into a tropical depression on October 4. Later that day, the depression turned to the northwest, and was upgraded to Tropical Storm Heather. Continuing to strengthen, on October 5, Heather strengthened into a hurricane, and later that day its winds peaked at 85 mph (135 km/h). Heather began to turn north-northwest around this time, and by October 6, it weakened into a tropical storm. Moving north, Heather continued to weaken over cooler waters, and on October 7, the final advisory was issued, downgrading Heather to a tropica