Antarctica/McMurdo. The UTC offset is UTC+12 in winter (standard time) and UTC+13 during daylight saving time (summer).Antarctica/McMurdo. Use this string in programming languages and APIs: JavaScript (`new Intl.DateTimeFormat('en-US', { timeZone: 'Antarctica/McMurdo' })`), Python (`pytz.timezone('Antarctica/McMurdo')`), or any IANA-compatible library.