Not All Sunrises Are Equal: How Latitude, Longitude, Time Zone, and Altitude Change When the Sun Comes Up
Why does the Sun rise at different times in different places? Find out!
Quick Reference: Sunrise Differences
- 4 main variables: latitude, longitude, time zone, altitude.
- Rule of thumb: sunrise moves ~4 minutes per 1 degree of longitude (about 60 miles east to west).
- Latitude effect (seasonal): the higher your latitude, the bigger the swing between summer and winter sunrise times.
- Altitude effect: ~1 minute earlier sunrise per 1,000 ft of elevation.
- Tool: the Almanac’s sunrise/sunset calculator for any US city.
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Related Almanac guides
Sources cited in this guide
Two cities can sit in the same time zone and watch the sun rise more than an hour apart on the same day. The reasons are geographic (latitude, longitude, altitude) and political (the time zone boundary). This guide is the math behind why sunrise times differ city to city, the four variables that decide your local sunrise to the minute, and the US extremes you can compare your hometown against.
The 4 Variables That Decide Your Local Sunrise
Per US Naval Observatory and NOAA solar-position research, four variables explain every difference in sunrise time between any two locations.
- Longitude (east-west). Sunrise moves ~4 minutes per degree of longitude. Boston and Cleveland are both in Eastern Time but Cleveland’s sunrise is 25 minutes later.
- Time zone (political). Time zones approximate but do not exactly match natural solar time. A city at the western edge of a zone has a much later clock-time sunrise.
- Latitude (north-south). Latitude does not move sunrise time uniformly; it changes how much sunrise SWINGS between summer and winter. At the equator, sunrise is ~6 a.m. year-round. At the Arctic Circle, it can be 24 hours of sun or 24 hours of dark.
- Altitude. ~1 minute earlier sunrise per 1,000 ft. The sun rises noticeably earlier on a mountaintop than in the valley below.
How to Calculate Sunrise to the Minute
Step by step using NOAA’s solar position calculator as the authoritative source.
- Get your latitude and longitude (any free mapping service, decimal degrees).
- Determine your time zone (UTC offset).
- Plug into NOAA’s solar position calculator with the date.
- Adjust for elevation if you are above 1,000 ft (subtract roughly 1 minute per 1,000 ft above sea level).
- Compare to the Almanac’s sunrise calculator, which incorporates all of these automatically by ZIP code.
Sunrise Variables and Calculation (Detail)
Below are the original detail sections on longitude, time zone, latitude, altitude, calculation adjustments, and US extremes.
Longitude
Longitude lines are the imaginary lines that run vertically around the globe, intersecting at the North and South Poles. Longitude is a way of talking about how far east or west a location is in relationship to one specific imaginary line, called the Prime Meridian, that runs through the town of Greenwich, England. Because the Earth spins clockwise, the Sun appears to the east of any given location each day. It takes about one hour for the Sun’s light to move 15° longitude. This is why the Sun’s rays reach the East Coast each day before the West Coast.
Time Zone
Time zones were created to acknowledge the fact that the Sun is not “up” at the same time everywhere around the globe. Because the Sun’s light moves across the Earth at a rate of 15° longitude per hour, people divided the Earth into 24 roughly equal sections of about 15° each, and assigned a one-hour time difference to each successive zone. This means that, all other things being equal, the Sun rises at roughly the same time no matter which time zone you’re in. Unfortunately, it’s not quite that simple. First of all, the many time zones don’t line up perfectly with the longitude lines, due to political and other complications. In addition, not all of us live right at the easternmost edge of our respective time zones. The further west you live within your time zone, the later your sunrise will be. There is a simple, but somewhat inexact, way to figure this out. For every 70 miles you travel west within your time zone, sunrise will be about four minutes later. This time decreases somewhat the further you move from the Equator, though. That’s because of latitude …
Latitude
Latitude lines are imaginary lines that encircle the globe horizontally. Latitude is a way of talking about how far north or south a location is in relationship to the Equator, the imaginary line that runs around the center of the globe. Unlike longitude lines, latitude lines never intersect. Because the Earth’s circumference is smaller near its poles than it is around its center, extreme northern or southern locations experience greater variations in the length of their days than locations closer to the Equator. While equatorial locations get approximately 12 hours of daylight and darkness each day, year-round, areas closer to the North and South Poles can experience several months of constant sunlight or darkness at a stretch. Most North Americans live somewhere between these two regions.
Altitude
As if all of these factors weren’t enough, altitude also plays a role. Generally speaking, the higher your location is, the earlier the Sun will rise, and the later it will set, compared to when it would for the same location if it were at sea level. An easy way to determine what effect altitude has is to remember than sunrise will be one minute earlier for every mile of altitude, and that sunset will be later by the same amount.
Sunrise Differences FAQ
Why does sunrise time differ between cities?
Four reasons. Longitude (about 4 minutes per degree east-west). Time zone (political, not solar). Latitude (controls how much summer-to-winter sunrise swings). Altitude (about 1 minute earlier per 1,000 ft up). Two cities in the same time zone can have very different sunrise times because of these factors.
How fast does sunrise time change day to day?
Around the solstices (December and June): less than 1 minute per day. Around the equinoxes (March and September): up to 3 minutes per day. The fastest sunrise-time change happens in mid-September, when sunrise can shift 21 minutes in a week at northern latitudes.
What city in the US has the earliest sunrise?
Per US Naval Observatory data, Quoddy Head (the eastern tip of Maine) sees the earliest mainland US sunrise most of the year. On midsummer day this is around 4:45 a.m. local time. Several offshore US territories (Guam, Wake Island) see earlier sunrise in clock time but use different time zones.
What city has the latest sunrise?
Among major US cities, Anchorage Alaska has the latest sunrise in late December (around 10:15 a.m.). Among lower-48 cities, those at the western edge of time zones with high latitudes have the latest clock-time sunrises: Marquette MI, International Falls MN, Caribou ME (in winter).
Does daylight saving time change sunrise?
Yes by 1 hour overnight, in March (forward) and November (back). The shift is purely clock-based; the actual solar event is unchanged. Per US Naval Observatory, this is why the second Sunday of March feels like one of the harshest sunrise shifts of the year.
Why is sunset later than 12 hours after sunrise?
Three reasons combine. Atmospheric refraction bends sunlight around the horizon, lengthening apparent day. The sun’s disc has finite size (you see the top edge before the center clears). And the date matters: on the equinoxes the day is slightly longer than 12 hours at every latitude.
Jaime McLeod
Jaime McLeod is a longtime journalist who has written for a wide variety of newspapers, magazines, and websites, including MTV.com. She enjoys the outdoors, growing and eating organic food, and is interested in all aspects of natural wellness.
- Jaime McLeod
- Jaime McLeod
- Jaime McLeod
- Jaime McLeod
Hello… my friend that has been living in Wyoming for 20 years plus has noticed that the sun rises and sets in different locations than it used to on same dates..!!And also that the sun rises earlier and also the sun sets later…once again on same dates.His home and neighbors homes and trees where not moved.This proves that the Earth has actually moved some and we are thinking perhaps that the 2004 Indonesia tsunami may have threw the earth of coarse a bit ….unless it is some kind of natural cycle the earth goes through every so many of thousand years,etc.This would also throw off the magnetic north point.Not much seems to be talked about at all anywhere that I can research.
The planets are in rotation of the earth and we travel 1 thousand miles away from home and turn around and head back 1 thousand years since I have all the keys I know when we turn and go home while no one else knows where we are going. The devil doesn’t know either nor his heathen friend and fa
There is the earth’s polar shift that is on the way that no one seems to talk about that is the main reason. I live in the same home for the past 23 years and the sun sets from a different location in June than it used to 23 years ago. The earth has tilted
Being on the very East end of a time zone (I am Central but one county over is Eastern) I’ve always HATED our early sunsets! It really isn’t that hard to understand but I have a difficult time explaining this to friends and family. Our “local” TV stations are in Marquette MI which is eastern. Everything they say is ET based. The summer sunset times they state are very late. I’m NOT a morning person so I couldn’t care less about sunrise time. When I talk to ppl about our stort winter afternoon daylight I swear I’m talking to a block of wood! We’re also quite far north (44N) so our winter days are short enough!! It’s not surprising how common S.A.D. is in this area once while traveling through in Alberta CA in mid June we were generally using the sun to judge when it was time to find a hotel. Imagine our surprise when we realized it was WELL After 10pm yet still not yet dark. VERY surreal.
Here in Maine, we are the Easternmost part of the Eastern Time Zone (and pretty far north!) and when it is dark at 4pm – it is rough! We hope you find some light this winter!
The time given for sunrise today in my location was 6:46 am. The sun did not appear for nearly three quarters of an hour, a little before 7:30 am. I was puzzled by this so I went looking for an answer. This is the only explanation I found. The curious thing is that the criteria for determining when sunrise would be was my zip code and the sun didnt appear til long after the time given. Is this an example of what you describe? Though my location was pinned by my zip code, the time given was actually for when the rising sun hit the edge of the time zone I am in? If not I am realy confused by this. Thank you!
Check the Wikipedia article on sunrise. It’s hard to determine the time of sunrise by watching the horizon!
If the horizon isn’t flat in your location, meaning that there is a hill, mountain, building, etc between you and the point where the sun rises on the horizon, you may not see the sun for some time after the published sunrise time, which does not account for local topography.
The earth spins counter-clockwise.
That is, when viewed from above the north pole.
dear sir
i was wondering whether there might be an official graph that plots the relationship between altitude and sunset provided by the national metereological society or US Navt etc for any given place on earth during the course of the year as simple as possible!!!
please steer me in the right direction!
thanks
thanks
Rabbi Gettinger
Rabbi Gettinger,
I don’t know of one, specifically, but if you consult with e agencies you mention, you may find one.