All times listed on the plots will have the following format:
12Z 14 OCT 01
HHZ DD MMM YY
where: HH is the Universal Time
DD is the day of the month
MMM is the month of the year
YY is the year.
Some plots will have a valid time listed such as:
24 hour Eta valid 12Z 14 FEB 02
The first part specifies how many hours beyond the initial time of observation the forecast is valid for. The label Eta specifies this is an Eta model result. The date/time data specifies the valid time, not the initial time.
Some plots will have local time listed such as:
4:00 PM EST [2100Z] 14 FEB 02
The plot is valid for 4PM EST on February 14. The value is brackets is the current Universal time (2100Z).
UTC - Universal Time
All weather information is tagged with the time of its observation or of its validity (for a forecast). For consistency, this is alway done using Greenwich Mean Time or Universal Time (UTC or Zulu time).
Time Zones
The Time Zones across North America and Pacific from East to West are:
Standard Daylight Savings
Time Time
Atlantic AST -4 ADT -3
Eastern EST -5 EDT -4
Central CST -6 CDT -5
Mountain MST -7 MDT -6
Pacific PST -8 PDT -7
Alaska
Hawaii
GMT time can be derived from any local time using the following table:
Standard time:
GMT ATL EST CST MST PST ALA HAW
difference -4 -5 -6 -7 -8 -9 -10
00 8P* 7P* 6P* 5P* 4P* 3P* 2P*
01 9P* 8P* 7P* 6P* 5P* 4P* 3P*
02 10P* 9P* 8P* 7P* 6P* 5P* 4P*
03 11P* 10P* 9P* 8P* 7P* 6P* 5P*
04 12A 11P* 10P* 9P* 8P* 7P* 6P*
05 1A 12A 11P* 10P* 9P* 8P* 7P*
06 2A 1A 12A 11P* 10P* 9P* 8P*
07 3A 2A 1A 12A 11P* 10P* 9P*
08 4A 3A 2A 1A 12A 11P* 10P*
09 5A 4A 3A 2A 1A 12A 11P*
10 6A 5A 4A 3A 2A 1A 12A
11 7A 6A 5A 4A 3A 2A 1A
12 8A 7A 6A 5A 4A 3A 2A
13 9A 8A 7A 6A 5A 4A 3A
14 10A 9A 8A 7A 6A 5A 4A
15 11A 10A 9A 8A 7A 6A 5A
16 12P 11A 10A 9A 8A 7A 6A
17 1P 12P 11A 10A 9A 8A 7A
18 2P 1P 12P 11A 10A 9A 8A
19 3P 2P 1P 12P 11A 10A 9A
20 4P 3P 2P 1P 12P 11A 10A
21 5P 4P 3P 2P 1P 12P 11A
22 6P 5P 4P 3P 2P 1P 12P
23 7P 6P 5P 4P 3P 2P 1P
* represents previous day
(i.e. 03 hours 23 January 93 is 8PM-MST 22 January)
Summertime (Daylight savings time) for those states that observe daylight savings time. For those that do not, use the standard time table all year:
GMT EDT CDT MDT PDT
difference -4 -5 -6 -7
00 8P* 7P* 6P* 5P*
01 9P* 8P* 7P* 6P*
02 10P* 9P* 8P* 7P*
03 11P* 10P* 9P* 8P*
04 12A 11P* 10P* 9P*
05 1A 12A 11P* 10P*
06 2A 1A 12A 11P*
07 3A 2A 1A 12A
08 4A 3A 2A 1A
09 5A 4A 3A 2A
10 6A 5A 4A 3A
11 7A 6A 5A 4A
12 8A 7A 6A 5A
13 9A 8A 7A 6A
14 10A 9A 8A 7A
15 11A 10A 9A 8A
16 12P 11A 10A 9A
17 1P 12P 11A 10A
18 2P 1P 12P 11A
19 3P 2P 1P 12P
20 4P 3P 2P 1P
21 5P 4P 3P 2P
22 6P 5P 4P 3P
23 7P 6P 5P 4P
* represents previous day
(i.e. 03 hours 23 June is 9PM-MDT 22 June)
