The incoming tropical moisture poses risks of flash flooding across Arizona, particularly in low-lying desert areas and mountainous regions. Heavy downpours could lead to localized flooding, making travel hazardous. Residents in flood-prone areas should remain vigilant and prepared for potential evacuation orders. Additionally, cooler temperatures and wet conditions may impact outdoor activities planned for Halloween weekend. The High Country and Phoenix metro area are expected to see significant rainfall, which could disrupt daily routines and events.