Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

  • most commonly as absolute values:  
    • instantaneous values,
    • averages over a period,
    • totals over a period,  
    • maxima or minima over a period.
  • sometimes as:

Medium range forecasts

Twice daily runs based on data times 00UTC and 12UTC are given in the ECMWF dissemination schedules:

The medium range ensemble (ENS):

...

...

...

...

...

...

...

For Members of the Boundary Conditions (BC) optional programme (members using ECMWF IFS model forecast values as boundary conditions for their own local areas models)

Twice daily runs based on data times 06UTC and 18UTC are given in the ECMWF dissemination schedules:

...

...

        • output parameters (Set III as shown for 06UTC and 18UTC base times.  Tropical Cyclone Tracks are also available for 06UTC and 18UTC base times)

...

    • has horizontal resolution of 9 Km and vertical resolution of 137 model levels.  These values are the same as those of the High Resolution (HRES) in earlier IFS versions.
    • has land-atmosphere and ocean-atmosphere coupling.
    • has 50 ensemble members plus an unperturbed control member (CTRL).
    • the unperturbed control member (CTRL) corresponds to the High Resolution (HRES) in earlier IFS versions.  CTRL forecasts maintain continuity of output for users.

Extended Range forecasts

The extended range ensemble:

Note: Precipitation forecasts are provided as values accumulated from the start of the forecast integration.  The range of the daily variation of the forecast 2m temperature and wind gust is best estimated by retrieving the forecast maximum and minimum values.  The combination of accumulated and instantaneous forecast information can occasionally lead to inconsistencies as in both cases the valid time is defined as the time at the end of the period (e.g. during the passage of a cold front when significant precipitation amounts might be accumulated by the IFS models over the whole time interval though instantaneous cloud-free conditions will be shown at the end of the interval).

Extended Range forecasts

Once daily runs based on data times 00UTC are given in the ECMWF dissemination schedules:

    • is run once daily:
      • base time 00UTC, producing a 46 day forecast (T+0 to T+960/1104).
        • Dissemination schedule -

...

...

...

    • has horizontal resolution of 36 Km and vertical resolution of 137 model levels.
    • has land-atmosphere and ocean-atmosphere coupling.
    • has 100 ensemble members plus an unperturbed control member (CONTROL).

Note:

Extended range products cover the period beyond the medium range forecasts (i.e. from day 15 to day 46).

Precipitation forecasts are provided as values accumulated from the start of the forecast integration.  The range of the daily variation of the forecast 2m temperature and wind gust is best estimated by retrieving the forecast maximum and minimum values.  The combination of accumulated and instantaneous forecast information can occasionally lead to inconsistencies as in both cases the valid time is defined as the time at the end of the period (e.g. during the passage of a cold front when significant precipitation amounts might be accumulated by the IFS models over the whole time interval though instantaneous cloud-free conditions will be shown at the end of the interval).

Seasonal forecasts

...

The seasonal range ensemble:

    • is run once monthly:
      • base time 00UTC on 1st of each month and run on the 5th of each

...

      • month producing a 7 month forecast (13 months every quarter).

For data:

Further information: