Definition
Time in Arizona refers to the civil time observed within the state of Arizona, United States, which is based on the Mountain Standard Time (MST) zone (UTC−07:00) and is largely maintained year‑round without the application of daylight‑saving time (DST).
Overview
Arizona is situated in the Mountain Time Zone of the United States. Unlike most states in this zone, Arizona does not advance clocks forward in the spring or revert them in the fall; the state remains on MST throughout the year. This practice results in Arizona sharing the same clock time as Pacific Daylight Time (PDT) during the summer months, while aligning with Mountain Standard Time in the winter.
Etymology / Origin
The concept of "time in Arizona" derives from the broader adoption of standardized time zones in the United States, instituted by the Standard Time Act of 1918. Arizona originally observed DST, but the state legislature repealed its participation in 1968, citing concerns about energy consumption and the impact on daily life in a desert climate. The term therefore reflects the legal and administrative decisions governing timekeeping within Arizona.
Characteristics
- Standard Time: Arizona follows Mountain Standard Time (UTC−07:00) year‑round.
- Daylight‑Saving Time Exception: The state does not observe DST, making its clocks one hour ahead of neighboring states that do observe DST during the summer (e.g., New Mexico, Colorado).
- Navajo Nation Exception: The Navajo Nation, which extends into northeastern Arizona, observes DST in accordance with federal law, shifting to Mountain Daylight Time (UTC−06:00) from the second Sunday in March to the first Sunday in November. This creates a time difference within Arizona's borders during the DST period.
- Historical Changes: Arizona briefly observed DST during World War II (the “War Time” period) and again during the 1970s energy crisis, but has maintained a consistent non‑DST stance since 1968, except for the Navajo Nation.
- Impact on Commerce and Communication: The uniform year‑round time simplifies scheduling for businesses operating within Arizona but requires coordination with out‑of‑state partners that observe DST.
Related Topics
- Mountain Time Zone (United States) – The broader time zone encompassing Arizona, Colorado, New Mexico, and parts of Canada.
- Daylight‑Saving Time in the United States – Federal and state regulations governing the seasonal adjustment of clocks.
- Time in the United States – Overview of the multiple time zones and DST practices across the country.
- Navajo Nation – A sovereign indigenous nation spanning parts of Arizona, New Mexico, and Utah, which observes DST contrary to the rest of Arizona.
- Standard Time Act of 1918 – Federal legislation that established standard time zones and DST in the United States.