Zulu Time Daylight Savings

It is within about 1 second of mean solar time at 0° longitude, and is not adjusted for daylight saving time. It is effectively a successor to Greenwich Mean Time (GMT). The coordination of time and frequency transmissions around the world began on 1 January 1960. Daylight Saving Time (DST) Information The Zulu time zone has been deemed obsolete. It has been replaced by Etc/UTC. +0000 - sign character (+) followed by a four digit time providing hours (00) and minutes (00) of the offset. Indicates zero hour and zero minutes time differences of the zero meridian. Military/NATO: Used by the U.S. Military, Chinese military and others Zulu - Military abbreviation for UTC.


With all the time zones in the world, pilots need a way to reference the current, past or future time, and not have to worry about what time zone they are in.

Daylight saving time is in effect from 0200 local time the second Sunday in March to 0200 local time the first Sunday in November. Canada and all U.S. Conterminous States observe daylight saving time except Arizona and Puerto Rico, and the Virgin Islands. Zulu, or Z Time is UTC Time, only by a different name. To understand where the 'z' comes from, consider the world's time zones. YEach is expressed as a certain number of hours 'ahead of UTC' or 'behind UTC'? (For example, UTC -5 is Eastern Standard Time.).

This is where Zulu Time comes into play. Because a pilot may cross several time zones during a flight, a standard time system has been adopted. It is called Universal Coordinated Time (UTC) and is referred to as Zulu time. UTC is the time at the 0° line of longitude which passes through Greenwich, England. All of the time zones around the world are based on this reference. It is presented in the local Military time at Greenwich, England

To convert to this time in the United States, a pilot should do the following:

Standard timeDaylight saving time
EasternAdd 5 HoursAdd 4 Hours
CentralAdd 6 HoursAdd 5 Hours
MountainAdd 7 HoursAdd 6 Hours
PacificAdd 8 HoursAdd 7 Hours

For daylight saving time, 1 hour should be subtracted from the calculated times.

Taken from the Pilots handbook of aeronautical knowledge (FAA-8083-25) Www.airtable.com.

In order to determine Zulu time, you must first convert the local time into military time:

To obtain Military time from local time:

After 12 PM, add or subtract 12
Before 12 PM, do nothing
Example:
2:00 pm: 2 + 12 = 14 or 1400 Military time
10:00 am = 1000 (ten hundred hours)
8:00 am = 0800 (zero eight hundred hours)

To obtain local time when Zulu time is known:
Zulu Time - Factor = Local Military time
To obtain Zulu time when local time is known:
Local Military Time + Factor = Zulu Time

Factor is the offset from GMT (Greenwich Mean Time). It can be obtained from the Airport / Facility Directory (A/FD)

Local Time Local Military Time Zulu Time (Summer +5) Zulu Time (Normal +6)
12:00 AM000005000600
1:00 AM010006000700
2:00 AM020007000800
3:00 AM030008000900
4:00 AM040009001000
5:00 AM050010001100
6:00 AM060011001200
7:00 AM070012001300
8:00 AM080013001400
9:00 AM090014001500
10:00 AM100015001600
11:00 AM110016001700
12:00 PM120017001800
1:00 PM130018001900
2:00 PM140019002000
3:00 PM150020002100
4:00 PM160021002200
5:00 PM170022002300
6:00 PM180023000000
7:00 PM190000000100
8:00 PM200001000200
9:00 PM210002000300
10:00 PM220003000400
11:00 PM230004000500

For example, the Texas A/FD shows that the offset for Houston is -6(-5DT). This means that this time zone is 6 hours behind Greenwich, and when daylight saving time is active, it is 5 hours behind.

Examples:

Determine Zulu time for a local time of 3:45 PM, and time zone of Central Standard Time (CST) (UTC-6(-5DT))

Time

3pm is after 12pm, so we add 12 (3 + 12 = 15), so 3:45 PM = 1545 Military

To obtain Zulu time when local time is known:
Local Military Time + Factor = Zulu Time

1545 + 6 Hours = 2145Z

Determine Zulu time for a local time of 9:30 AM, and time zone of Central Daylight Time (CDT) (UTC-6(-5DT))

9 AM is before 12 pm, so we don't add or subtract anything to get military time:
9:30 AM = 0930 Local Military Time

To obtain Zulu time when local time is known:
Local Military Time + Factor = Zulu Time

0930 + 5 hours = 3:30 PM

(Note we used 5, and not 6. In this example, we are on daylight saving time. (CDT))

Zulu Time And Daylight Savings

3pm is after 12pm, so we add 12 (3 + 12 = 15), so 3:30 PM = 1530 Zulu Time

Determine local time for a Zulu time of 1710Z, and time Zone of Eastern Daylight Time (EDT) (UTC-5(-4DT))

Set Daylight Savings Time On Windows 10

To obtain local time when Zulu time is known:
Zulu Time - Factor = Local Military time

1710 - 4 hours = 1310 Local Military time

(Note we used 4, and not 5. In this example, we are on daylight saving time. (EDT))

13 is greater than 12, so our time will be in PM. We subtract 12, and get 1

1310 Local Military time = 1:10 PM

The A/FD is digitally available to the public. You can download and print excerpts from any A/FD in print from the internet:

For more information, follow the link below to the FAA's AIM (Aeronautical Information Manual) article on Time:


All aspects of meteorology are based upon a world-wide 24-hour clock called Zulu time (Z), more commonly called Coordinated Universal Time (UTC). You will notice all weather maps, radar, and satellite images all have their time expressed in 'Z'. The Zulu term stems from military usage while Coordinated Universal Time is the civilian term for this 24-hour clock.

The origin of these time zones began in the mid 1800's in England. In 1852 the Royal Observatory in Greenwich, England began transmitting time telegraphically and just three years later became the standard time in most of Great Britain. Also, charts and maps were made with reference to the observatory as the 'zero' or prime meridian.

Does Zulu Time Use Daylight Savings

Over the next few decades a number of locations around the world had developed their own meridians as reference points. The Greenwich meridian was the most popular of these in part due to the reputation for reliability and correctness of the Greenwich Observatory's publications of navigational data.

In 1884, a conference in Washington, D.C. settled the matter where it was agreed to establish a single 'prime' meridian (0° longitude), passing through Greenwich. This was for both for longitude and timekeeping. This 0° meridian divides the Eastern from the Western Hemisphere. Today, one can visit the Royal Observatory and straddle this 0° meridian with one foot in each hemisphere.

With the 360° daily rotation of the earth, the sun is moving 15° each hour which leads to the formation of 24 time zones. However, today the individual zone boundaries are no longer straight, nor are they always continuous, as they have been modified for convenience and to satisfy the desires of sovereign nations.

Time zone offsets are identified as -12 UTC through 0 to +12 UTC with the minus values signifying time 'before' or ahead of prime meridian (which is the Western Hemisphere). At the meeting of the -12 and +12 time zones is the International Date Line.

Moving west across the International Date Line one moves from the -12 UTC time zone to the +12 UTC time zone. This means you advance the clock 24 hours; in essence you advance one day on the calendar. Moving east across the International Date Line means subtracting 24 hours from the clock thereby reversing one day on the calendar.

The 24-hour clock (Z-time) begins at midnight (00Z) at this prime meridian. 00Z for the United States begins in the evening local time. Z-time does not change with the change for daylight saving time but the local time will change. For example, 00Z in the Central STANDARD Time is at 6:00 p.m. but 00Z occurs at 7:00 p.m. in Central DAYLIGHT SAVING Time.

Zulu Time Daylight Savings

The following tables show z-times for each time zone in the United States and U.S. Territories.

Standard Time (UTC offset)
Z-timeGuam
(+10)
Hawaii
(-10)
Alaska
(-9)
Pacific
(-8)
Mountain
(-7)
Central
(-6)
Eastern
(-5)
Atlantic
(-4)
00z10 a.m.2 p.m.*3 p.m.*4 p.m.*5 p.m.*6 p.m.*7 p.m.*8 p.m.*
01z11 a.m.3 p.m.*4 p.m.*5 p.m.*6 p.m.*7 p.m.*8 p.m.*9 p.m.*
02z12 noon4 p.m.*5 p.m.*6 p.m.*7 p.m.*8 p.m.*9 p.m.*10 p.m.*
03z1 p.m.5 p.m.*6 p.m.*7 p.m.*8 p.m.*9 p.m.*10 p.m.*11 p.m.*
04z2 p.m.6 p.m.*7 p.m.*8 p.m.*9 p.m.*10 p.m.*11 p.m.*12 mid
05z3 p.m.7 p.m.*8 p.m.*9 p.m.*10 p.m.*11 p.m.*12 mid1 a.m.
06z4 p.m.8 p.m.*9 p.m.*10 p.m.*11 p.m.*12 mid1 a.m.2 a.m.
07z5 p.m.9 p.m.*10 p.m.*11 p.m.*12 mid1 a.m.2 a.m.3 a.m.
08z6 p.m.10 p.m.*11 p.m.*12 mid1 a.m.2 a.m.3 a.m.4 a.m.
09z7 p.m.11 p.m.*12 mid1 a.m.2 a.m.3 a.m.4 a.m.5 a.m.
10z8 p.m.12 mid1 a.m.2 a.m.3 a.m.4 a.m.5 a.m.6 a.m.
11z9 p.m.1 a.m.2 a.m.3 a.m.4 a.m.5 a.m.6 a.m.7 a.m.
12z10 p.m.2 a.m.3 a.m.4 a.m.5 a.m.6 a.m.7 a.m.8 a.m.
13z11 p.m.3 a.m.4 a.m.5 a.m.6 a.m.7 a.m.8 a.m.9 a.m.
14z12 mid4 a.m.5 a.m.6 a.m.7 a.m.8 a.m.9 a.m.10 a.m.
15z1 a.m.#5 a.m.6 a.m.7 a.m.8 a.m.9 a.m.10 a.m.11 a.m.
16z2 a.m.#6 a.m.7 a.m.8 a.m.9 a.m.10 a.m.11 a.m.12 noon
17z3 a.m.#7 a.m.8 a.m.9 a.m.10 a.m.11 a.m.12 noon1 p.m.
18z4 a.m.#8 a.m.9 a.m.10 a.m.11 a.m.12 noon1 p.m.2 p.m.
19z5 a.m.#9 a.m.10 a.m.11 a.m.12 noon1 p.m.2 p.m.3 p.m.
20z6 a.m.#10 a.m.11 a.m.12 noon1 p.m.2 p.m.3 p.m.4 p.m.
21z7 a.m.#11 a.m.12 noon1 p.m.2 p.m.3 p.m.4 p.m.5 p.m.
22z8 a.m.#12 noon1 p.m.2 p.m.3 p.m.4 p.m.5 p.m.6 p.m.
23z9 a.m.#1 p.m.2 p.m.3 p.m.4 p.m.5 p.m.6 p.m.7 p.m.
Note: *The previous day #The next day

Uk Daylight Savings Time 2017

Daylight Saving Time (UTC offset)
Z-timeGuam
(+10)
Hawaii
(-10)
Alaska
(-8)
Pacific
(-7)
Mountain
(-6)
Central
(-5)
Eastern
(-4)
Atlantic
(-3)
00z10 a.m.2 p.m.*4 p.m.*5 p.m.*6 p.m.*7 p.m.*8 p.m.*9 p.m.*
01z11 a.m.3 p.m.*5 p.m.*6 p.m.*7 p.m.*8 p.m.*9 p.m.*10 p.m.*
02z12 noon4 p.m.*6 p.m.*7 p.m.*8 p.m.*9 p.m.*10 p.m.*11 p.m.*
03z1 p.m.5 p.m.*7 p.m.*8 p.m.*9 p.m.*10 p.m.*11 p.m.*12 mid
04z2 p.m.6 p.m.*8 p.m.*9 p.m.*10 p.m.*11 p.m.*12 mid1 a.m.
05z3 p.m.7 p.m.*9 p.m.*10 p.m.*11 p.m.*12 mid1 a.m.2 a.m.
06z4 p.m.8 p.m.*10 p.m.*11 p.m.*12 mid1 a.m.2 a.m.3 a.m.
07z5 p.m.9 p.m.*11 p.m.*12 mid1 a.m.2 a.m.3 a.m.4 a.m.
08z6 p.m.10 p.m.*12 mid1 a.m.2 a.m.3 a.m.4 a.m.5 a.m.
09z7 p.m.11 p.m.*1 a.m.2 a.m.3 a.m.4 a.m.5 a.m.6 a.m.
10z8 p.m.12 mid2 a.m.3 a.m.4 a.m.5 a.m.6 a.m.7 a.m.
11z9 p.m.2 a.m.3 a.m.4 a.m.5 a.m.6 a.m.7 a.m.8 a.m.
12z10 p.m.2 a.m.4 a.m.5 a.m.6 a.m.7 a.m.8 a.m.9 a.m.
13z11 p.m.3 a.m.5 a.m.6 a.m.7 a.m.8 a.m.9 a.m.10 a.m.
14z12 mid4 a.m.6 a.m.7 a.m.8 a.m.9 a.m.10 a.m.11 a.m.
15z1 a.m.#5 a.m.7 a.m.8 a.m.9 a.m.10 a.m.11 a.m.12 noon
16z2 a.m.#6 a.m.8 a.m.9 a.m.10 a.m.11 a.m.12 noon1 p.m.
17z3 a.m.#7 a.m.9 a.m.10 a.m.11 a.m.12 noon1 p.m.2 p.m.
18z4 a.m.#8 a.m.10 a.m.11 a.m.12 noon1 p.m.2 p.m.3 p.m.
19z5 a.m.#9 a.m.11 a.m.12 noon1 p.m.2 p.m.3 p.m.4 p.m.
20z6 a.m.#10 a.m.12 noon1 p.m.2 p.m.3 p.m.4 p.m.5 p.m.
21z7 a.m.#11 a.m.1 p.m.2 p.m.3 p.m.4 p.m.5 p.m.6 p.m.
22z8 a.m.#12 noon2 p.m.3 p.m.4 p.m.5 p.m.6 p.m.7 p.m.
23z9 a.m.#1 p.m.3 p.m.4 p.m.5 p.m.6 p.m.7 p.m.8 p.m.
Note: *The previous day #The next day

Daylight Savings Time And Zulu Time

Regardless which National Weather Service weather map, radar, or satellite picture you view, be sure to first check the time of the image as it will be reported in 24-hour 'Z' time.