What is UTC or Z time, and how do I convert it to my local time?

UTC literally stands for Universal Time Coordinated (though it is typically referred to as Coordinated Universal Time) and is the standard time common to every place in the world.  It is also known as Greenwich Mean Time (GMT) and Zulu (Z).  UTC is defined as the time at longitude 0 degrees, the prime meridian.  This is the longitudinal line that separates the Eastern and Western Hemispheres, and happens to pass through the Greenwich Observatory outside of London, England.  All of our forecast products and the computer models that provide us guidance are based on this universal time zone.

When you see 12 UTC or 1200 UTC or 12Z (all are the same and depend on forecaster preference), it refers to noon at Greenwich.  00 UTC or 00Z is midnight Greenwich time.  Translating this to your time zone depends on where you live.  Below is a table that provides some UTC times and their conversion to the 4 main time zones over the lower 48 for standard time.

STANDARD TIME
 
 
PACIFIC
MOUNTAIN
CENTRAL
EASTERN
0000Z/UTC
4:00 PM
5:00 PM
6:00 PM
7:00 PM
0300
7:00 PM
8:00 PM
9:00 PM
10:00 PM
0600
10:00 PM
11:00 PM
Midnight
1:00 AM
0900
1:00 AM
2:00 AM
3:00 AM
4:00 AM
1200
4:00 AM
5:00 AM
6:00 AM
7:00 AM
1500
7:00 AM
8:00 AM
9:00 AM
10:00 AM
1800
10:00 AM
11:00 AM
Noon
1:00 PM
2100
1:00 PM
2:00 PM
3:00 PM
4:00 PM

So, for example, if we write 12Z Friday, itíll be 7:00 a.m. Eastern Standard Time and 4:00 a.m. Pacific.  If itís 00Z Friday, it will be 7:00 p.m. Thursday Eastern and 4:00 p.m. Thursday Pacific.

The table below is for daylight time.

DAYLIGHT TIME
 
PACIFIC MOUNTAIN CENTRAL EASTERN
0000Z/UTC
5:00 PM
6:00 PM
7:00 PM
8:00 PM
0300
8:00 PM
9:00 PM
10:00 PM
11:00 PM
0600
11:00 PM
Midnight
1:00 AM
2:00 AM
0900
2:00 AM
3:00 AM
4:00 AM
5:00 AM
1200
5:00 AM
6:00 AM
7:00 AM
8:00 AM
1500
8:00 AM
9:00 AM
10:00 AM
11:00 AM
1800
11:00 AM
Noon
1:00 PM
2:00 PM
2100
2:00 PM
3:00 PM
4:00 PM
5:00 PM