This example describes an instantaneous field valid on 20120103 00Z from a forecast starting on 20120101 00Z (time step=48 hours) .
- In bold, the values are fixed. They are meant to be used by all partners
- In green, these are the values for the example.
| Time ( instantaneous ) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Start of forecast ( section 1 ) | |||||||||
Octetsreforecast | Octets real time | Fixed values to be used by all the partners | Example | 12values | Meaning of values | Grib_api values | |||
| 12 | Significance of Reference Time | =1 | Start of forecast | = 1 | |||||
| 13-14 | 13-14 | Year (four digits) | 2012 | year of start of forecast |
dataDate= | 20121520120101 dataTime=0 | |||
| 15 | Month | 01 | month of start of forecast | = 01 | 16 | ||||
| 16 | Day | 01 | day of start of forecast | = 01||||||
| 17 | 17 | Hour | 00 | hour of start of forecast | = 00 | ||||
| section 4 e.g. template 4.1 | |||||||||
| 18 | 18 | Indicator of unit of time range | = 11 | Hour | = 1 | 19-22||||
| 19-22 | Forecast time | = 0 | = 0 | ||||||
| 45-46 | 38-39 | year of end of overall time interval |
End of accumulated period | = 2012 | |||||
| 47 | 40 | month of end of overall time interval | = 01 | ||||||
| 48 | 41 | day of end of overall time interval | = 03 | ||||||
| 49 | 42 | hour of end of overall time interval | = 00 | ||||||
| 52 | 45 | number of time ranges | = 4 6 hourly fields used in average | ||||||
| 53-56 | 46-49 | total number of data values missing in statistical process | = 0 | = 0 | |||||
| 57 | 50 | Statistical process used to calculate the processed field from the field at each time increment during the time range | = 1 | Accumulated | = 0 | ||||
| 58 | 51 | Type of time increment between successive fields used in the statistical processing | = 2 | Successive times processed have same start time of forecast, forecast time is incremented | = 2 | ||||
| 59 | 52 | Indicator of unit of time for time range over which statistical processing is done | = 1 | Hour | = 1 | ||||
| 60-63 | 53-56 | Length of the time range over which statistical processing is done, in units defined by the previous octet | Time step (in hour) at the end of the accumulation | = 48 | |||||
| 64 | 57 | Indicator of unit of time for the increment between the successive fields used | = 255 | Missing | = 255 | ||||
| 65-68 | 58-61 | Time increment between successive fields, in units defined by the previous octet | = 0 | Time frequency used to compute the daily mean | = 0 6 hourly fields used in average | ||||
Time ( reforecast ) section 4, template 4.61 | ||
|---|---|---|
| Example | ||
| 38-39 | Year of model version | 2013 |
| 40 | Month of model version | 01 |
| 41 | Day of model version | 01 |
| 42 | Hour of model version | 00 |
| 43 | minute of model version | 00 |
| 44 | second of model version | 00 |
The example of reforecast with the example of daily average define together a reforecast of the daily average valid for 2/1/2012 computed with a model version operational on the 1/1/2013.
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| 48 | Forecast step | stepType=instant, step=48 |
|---|
Examples of grib2 headers: