Set VI - Atmospheric Model Ensemble extended forecast (ENS extended)

Twice a week, the ENS model is extended up to 46 days. ENS extended products comprise ensembles of individual forecasts and post-processed products of average conditions (e.g. weekly averages) and the associated uncertainty.

The following sub-sets are available from the ENS extended (Monthly) on both Monday and Thursday runs:

VI-i: Weekly means of ensemble means (including re-forecast products)

VI-ii: Weekly mean anomalies of ensemble means

VI-iii: Weekly means of individual ensemble members (including re-forecast products)

VI-iv: Weekly mean anomalies of individual ensemble members

VI-v: Individual forecast runs (including re-forecast products)

VI-vi: Probabilities (weekly products)

Product description

EFOV fields at step 360 (change of resolution) can be provided for accumulated fields upon request at no extra cost to customers purchasing the corresponding fields.

Dissemination schedule

(dissemination data stream indicator = F for real-time forecasts)

(dissemination data stream indicator = H for re-forecasts)

Forecast product Time available

Real Time Forecast

20:00 (Mon/ Thu)
Re-forecast 21:00 (Mon / Thu)

Parameters

All tables are sortable by column. Use your browser search for specific parameters.

  Terms conventions
(inv) Invariant field. If requested these parameters can be provided free of charge

VI-i: Weekly means of ensemble means (including reforecast products)

Base time 00 UTC only

Forecast ranges

2 runs (Monday and Thursday), four 7-day ranges per run

  Forecast time ranges Resolution
Monday

0-168/168-336/336-504/504-672

  • 0.4° x 0.4° lat/long grid or any multiple thereof (global or sub-area)
  • On model (Octahedral) O320 grid (global or sub-area)
  • Spectral components (TCO319) for upper-air fields (global area only)
Thursday

96-264/264-432/432-600/600-768


VI-i-a: Weekly means of ensemble means - Single level

Short Name ID Long Name Description Units Additional information
rsn 33 Snow density This parameter is the mass of snow per cubic metre in the snow layer.

The ECMWF Integrated Forecast System (IFS) model represents snow as a single additional layer over the uppermost soil level. The snow may cover all or part of the grid box.

See further information on snow in the IFS.
kg m**-3  
sst 34 Sea surface temperature This parameter is the temperature of sea water near the surface.

This parameter is taken from various providers, who process the observational data in different ways. Each provider uses data from several different observational sources. For example, satellites measure sea surface temperature (SST) in a layer a few microns thick in the uppermost mm of the ocean, drifting buoys measure SST at a depth of about 0.2-1.5m, whereas ships sample sea water down to about 10m, while the vessel is underway. Deeper measurements are not affected by changes that occur during a day, due to the rising and setting of the Sun (diurnal variations).

Sometimes this parameter is taken from a forecast made by coupling the NEMO ocean model to the ECMWF Integrated Forecasting System. In this case, the SST is the average temperature of the uppermost metre of the ocean and does exhibit diurnal variations.

See further documentation .

This parameter has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.
K  
cape 59 Convective available potential energy This is an indication of the instability (or stability) of the atmosphere and can be used to assess the potential for the development of convection, which can lead to heavy rainfall, thunderstorms and other severe weather.

In the ECMWF Integrated Forecasting System (IFS), CAPE is calculated by considering parcels of air departing at different model levels below the 350 hPa level. If a parcel of air is more buoyant (warmer and/or with more moisture) than its surrounding environment, it will continue to rise (cooling as it rises) until it reaches a point where it no longer has positive buoyancy. CAPE is the potential energy represented by the total excess buoyancy. The maximum CAPE produced by the different parcels is the value retained.

Large positive values of CAPE indicate that an air parcel would be much warmer than its surrounding environment and therefore, very buoyant. CAPE is related to the maximum potential vertical velocity of air within an updraft; thus, higher values indicate greater potential for severe weather. Observed values in thunderstorm environments often may exceed 1000 joules per kilogram (J kg-1), and in extreme cases may exceed 5000 J kg-1.

The calculation of this parameter assumes: (i) the parcel of air does not mix with surrounding air; (ii) ascent is pseudo-adiabatic (all condensed water falls out) and (iii) other simplifications related to the mixed-phase condensational heating.
J kg**-1  
tclw 78 Total column cloud liquid water Vertical integral of cloud liquid water content kg m**-2  
tciw 79 Total column cloud ice water Vertical integral of cloud ice water content kg m**-2  
mx2t6 121 Maximum temperature at 2 metres in the last 6 hours - K  
mn2t6 122 Minimum temperature at 2 metres in the last 6 hours - K  
z 129 Geopotential This parameter is the gravitational potential energy of a unit mass, at a particular location, relative to mean sea level. It is also the amount of work that would have to be done, against the force of gravity, to lift a unit mass to that location from mean sea level.

The geopotential height can be calculated by dividing the geopotential by the Earth's gravitational acceleration, g (=9.80665 m s-2). The geopotential height plays an important role in synoptic meteorology (analysis of weather patterns). Charts of geopotential height plotted at constant pressure levels (e.g., 300, 500 or 850 hPa) can be used to identify weather systems such as cyclones, anticyclones, troughs and ridges.

At the surface of the Earth, this parameter shows the variations in geopotential (height) of the surface, and is often referred to as the orography.
m**2 s**-2  
tcw 136 Total column water This parameter is the sum of water vapour, liquid water, cloud ice, rain and snow in a column extending from the surface of the Earth to the top of the atmosphere. In old versions of the ECMWF model (IFS), rain and snow were not accounted for. kg m**-2  
tcwv 137 Total column water vapour Vertically integrated water vapour kg m**-2  
stl1 139 Soil temperature level 1 This parameter is the temperature of the soil in layer 1 (0 - 7cm, the surface is at 0cm).

The ECMWF Integrated Forecasting System model has a four-layer representation of soil:
Layer 1: 0 -7cm
Layer 2: 7 -21cm
Layer 3: 21-72cm
Layer 4: 72-189cm

Soil temperature is set at the middle of each layer, and heat transfer is calculated at the interfaces between them. It is assumed that there is no heat transfer out of the bottom of the lowest layer.

This parameter has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.

See further information.
K  
sd 141 Snow depth This parameter is the depth of snow from the snow-covered area of a grid box.

Its units are metres of water equivalent, so it is the depth the water would have if the snow melted and was spread evenly over the whole grid box. The ECMWF Integrated Forecast System represents snow as a single additional layer over the uppermost soil level. The snow may cover all or part of the grid box.

See further information.
m of water equivalent  
msl 151 Mean sea level pressure This parameter is the pressure (force per unit area) of the atmosphere adjusted to the height of mean sea level.

t is a measure of the weight that all the air in a column vertically above the area of Earth's surface would have at that point, if the point were located at the mean sea level. It is calculated over all surfaces - land, sea and in-land water.

Maps of mean sea level pressure are used to identify the locations of low and high pressure systems, often referred to as cyclones and anticyclones. Contours of mean sea level pressure also indicate the strength of the wind. Tightly packed contours show stronger winds.

The units of this parameter are pascals (Pa). Mean sea level pressure is often measured in hPa and sometimes is presented in the old units of millibars, mb (1 hPa = 1 mb = 100 Pa).
Pa  
tcc 164 Total cloud cover This parameter is the proportion of a grid box covered by cloud. Total cloud cover is a single level field calculated from the cloud occurring at different model levels through the atmosphere. Assumptions are made about the degree of overlap/randomness between clouds at different heights.

Cloud fractions vary from 0 to 1.
(0 - 1)  
10u 165 10 metre U wind component This parameter is the eastward component of the 10m wind. It is the horizontal speed of air moving towards the east, at a height of ten metres above the surface of the Earth, in metres per second.

Care should be taken when comparing this parameter with observations, because wind observations vary on small space and time scales and are affected by the local terrain, vegetation and buildings that are represented only on average in the ECMWF Integrated Forecasting System.

This parameter can be combined with the V component of 10m wind to give the speed and direction of the horizontal 10m wind.
m s**-1  
10v 166 10 metre V wind component This parameter is the northward component of the 10m wind. It is the horizontal speed of air moving towards the north, at a height of ten metres above the surface of the Earth, in metres per second.

Care should be taken when comparing this parameter with observations, because wind observations vary on small space and time scales and are affected by the local terrain, vegetation and buildings that are represented only on average in the ECMWF Integrated Forecasting System.

This parameter can be combined with the U component of 10m wind to give the speed and direction of the horizontal 10m wind.
m s**-1  
2t 167 2 metre temperature This parameter is the temperature of air at 2m above the surface of land, sea or in-land waters.

2m temperature is calculated by interpolating between the lowest model level and the Earth's surface, taking account of the atmospheric conditions. See further information .

This parameter has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.
K  
2d 168 2 metre dewpoint temperature This parameter is the temperature to which the air, at 2 metres above the surface of the Earth, would have to be cooled for saturation to occur.

It is a measure of the humidity of the air. Combined with temperature and pressure, it can be used to calculate the relative humidity.

2m dew point temperature is calculated by interpolating between the lowest model level and the Earth's surface, taking account of the atmospheric conditions. See further information.This parameter has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.
K  
lsm 172 Land-sea mask This parameter is the proportion of land, as opposed to sea or in-land waters, in a grid box.

This parameter has values ranging between zero and one and is dimensionless.

Grid boxes in the ECWMF Integrated Forecast System with a value above 0.5 are treated as wholly land (and inland waters). Those with a value below 0.5 are treated as ocean.
(0 - 1)  
mx2t 201 Maximum temperature at 2 metres since previous post-processing This parameter is the highest temperature of air at 2m above the surface of land, sea or in-land waters since the parameter was last archived in a particular forecast.

2m temperature is calculated by interpolating between the lowest model level and the Earth's surface, taking account of the atmospheric conditions. See further information .

This parameter has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.
K  
mn2t 202 Minimum temperature at 2 metres since previous post-processing This parameter is the lowest temperature of air at 2m above the surface of land, sea or in-land waters since the parameter was last archived in a particular forecast.

2m temperature is calculated by interpolating between the lowest model level and the Earth's surface, taking account of the atmospheric conditions. See further information .

This parameter has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.
K  
~ 172142 Stratiform precipitation (Large-scale precipitation) - m s**-1  
cprate 172143 Convective precipitation - m s**-1  
~ 172144 Snowfall (convective + stratiform) - m of water equivalent s**-1  
~ 172189 Sunshine duration - ~  
tprate 172228 Total precipitation - m s**-1  
100u 228246 100 metre U wind component - m s**-1  
100v 228247 100 metre V wind component - m s**-1  
sts 234139 Surface temperature significance - %  
2ts 234167 2 metre temperature significance - %  
tps 234228 Total precipitation significance - %  

VI-i-b: Weekly means of ensemble means - Pressure levels

Available at 10/50/100/200/300/400/500/700/850/925/1000 hPa unless otherwise specified.

Short Name ID Long Name Description Units Additional information
strf 1 Stream function - m**2 s**-1  
vp 2 Velocity potential - m**2 s**-1  
z 129 Geopotential This parameter is the gravitational potential energy of a unit mass, at a particular location, relative to mean sea level. It is also the amount of work that would have to be done, against the force of gravity, to lift a unit mass to that location from mean sea level.

The geopotential height can be calculated by dividing the geopotential by the Earth's gravitational acceleration, g (=9.80665 m s-2). The geopotential height plays an important role in synoptic meteorology (analysis of weather patterns). Charts of geopotential height plotted at constant pressure levels (e.g., 300, 500 or 850 hPa) can be used to identify weather systems such as cyclones, anticyclones, troughs and ridges.

At the surface of the Earth, this parameter shows the variations in geopotential (height) of the surface, and is often referred to as the orography.
m**2 s**-2  
t 130 Temperature This parameter is the temperature in the atmosphere.

It has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.

This parameter is available on multiple levels through the atmosphere. More information about availability here.
K  
u 131 U component of wind This parameter is the eastward component of the wind. It is the horizontal speed of air moving towards the east, in metres per second. A negative sign thus indicates air movement towards the west.

This parameter can be combined with the V component of wind to give the speed and direction of the horizontal wind.
m s**-1  
v 132 V component of wind This parameter is the northward component of the wind. It is the horizontal speed of air moving towards the north, in metres per second. A negative sign thus indicates air movement towards the south.

This parameter can be combined with the U component of wind to give the speed and direction of the horizontal wind.
m s**-1  
q 133 Specific humidity This parameter is the mass of water vapour per kilogram of moist air.

The total mass of moist air is the sum of the dry air, water vapour, cloud liquid, cloud ice, rain and falling snow.
kg kg**-1  

VI-ii: Weekly mean anomalies of ensemble means

Base time 00UTC only

Forecast ranges

2 runs (Monday and Thursday), four 7-day ranges per run

  Forecast time ranges Resolution
Monday

0-168/168-336/336-504/504-672

  • 0.4° x 0.4° lat/long grid or any multiple thereof (global or sub-area)
  • On model (Octahedral) O320 grid (global or sub-area)
  • Spectral components (TCO319) for upper-air fields (global area only)
Thursday

96-264/264-432/432-600/600-768

VI

VI-ii-a: Weekly mean anomalies of ensemble means -Single level

Short Name ID Long Name Description Units Additional information
z 129 Geopotential This parameter is the gravitational potential energy of a unit mass, at a particular location, relative to mean sea level. It is also the amount of work that would have to be done, against the force of gravity, to lift a unit mass to that location from mean sea level.

The geopotential height can be calculated by dividing the geopotential by the Earth's gravitational acceleration, g (=9.80665 m s-2). The geopotential height plays an important role in synoptic meteorology (analysis of weather patterns). Charts of geopotential height plotted at constant pressure levels (e.g., 300, 500 or 850 hPa) can be used to identify weather systems such as cyclones, anticyclones, troughs and ridges.

At the surface of the Earth, this parameter shows the variations in geopotential (height) of the surface, and is often referred to as the orography.
m**2 s**-2  
lsm 172 Land-sea mask This parameter is the proportion of land, as opposed to sea or in-land waters, in a grid box.

This parameter has values ranging between zero and one and is dimensionless.

Grid boxes in the ECWMF Integrated Forecast System with a value above 0.5 are treated as wholly land (and inland waters). Those with a value below 0.5 are treated as ocean.
(0 - 1)  
100ua 171006 100 metre U wind component anomaly - m s**-1  
100va 171007 100 metre V wind component anomaly - m s**-1  
rsna 171033 Snow density anomaly - kg m**-3  
ssta 171034 Sea surface temperature anomaly - K  
capea 171059 Convective available potential energy anomaly - J kg**-1  
tclwa 171078 Total column liquid water anomaly - kg m**-2  
tciwa 171079 Total column ice water anomaly - kg m**-2  
mx2t6a 171121 Maximum temperature at 2 metres in the last 6 hours anomaly - K  
mn2t6a 171122 Minimum temperature at 2 metres in the last 6 hours anomaly - K  
tcwa 171136 Total column water anomaly - kg m**-2  
tcwva 171137 Total column water vapour anomaly - kg m**-2  
sda 171141 Snow depth anomaly - m of water equivalent  
msla 171151 Mean sea level pressure anomaly - Pa  
tcca 171164 Total cloud cover anomaly - (0 - 1)  
10ua 171165 10 metre U wind component anomaly - m s**-1  
10va 171166 10 metre V wind component anomaly - m s**-1  
2ta 171167 2 metre temperature anomaly - K  
2da 171168 2 metre dewpoint temperature anomaly - K  
mx2ta 171201 Maximum temperature at 2 metres anomaly - K  
mn2ta 171202 Minimum temperature at 2 metres anomaly - K  
sfara 173144 Snowfall (convective + stratiform) anomalous rate of accumulation - m of water equivalent s**-1  
sundara 173189 Sunshine duration anomalous rate of accumulation - dimensionless  
tpara 173228 Total precipitation anomalous rate of accumulation - m s**-1  

VI-ii-b: Weekly mean anomalies of ensemble means - Pressure levels

Available at 1000, 925, 850, 700, 500, 400, 300, 200, 100, 50, 20 hPa unless otherwise specified.

Short Name ID Long Name Description Units Additional information
strfa 171001 Stream function anomaly - m**2 s**-1  
vpota 171002 Velocity potential anomaly - m**2 s**-1  
ta 171130 Temperature anomaly - K  
ua 171131 U component of wind anomaly - m s**-1  
va 171132 V component of wind anomaly - m s**-1  
qa 171133 Specific humidity anomaly - kg kg**-1  
gha 171156 Height anomaly - m  

VI-iii: Weekly means of individual ensemble member forecasts (including reforecast products)

Base time 00UTC only

Forecast ranges

2 runs (Monday and Thursday), four 7-day ranges per run

  Forecast time ranges Resolution
Monday

0-168/168-336/336-504/504-672

  • 0.4° x 0.4° lat/long grid or any multiple thereof (global or sub-area)
  • On model (Octahedral) O320 grid (global or sub-area)
  • Spectral components (TCO319) for upper-air fields (global area only)
Thursday

96-264/264-432/432-600/600-768

VI-iii-a: Weekly means of individual ensemble member forecasts - single level

Short Name ID Long Name Description Units Additional information
ci 31 Sea ice area fraction This parameter is the fraction of a grid box which is covered by sea-ice. Sea-ice can only occur in a grid box which is defined as ocean according to the land sea mask at the resolution being used. Sea-ice cover can also be known as sea-ice fraction or sea-ice concentration.

Sea-ice cover in the ECMWF Integrated Forecasting System (IFS) is derived from observations, its formation/melting is not simulated by the model, however the model does take account of the way that sea ice alters the interaction between the atmosphere and ocean.

Sea-ice is frozen sea water which floats on the surface of the ocean. Sea-ice does not include ice which forms on land such as glaciers, icebergs and ice-sheets. It also excludes ice shelves which are anchored on land, but protrude out over the surface of the ocean. These phenomena are not modelled by the IFS.

Long-term monitoring of sea-ice cover is important for understanding climate change. Sea-ice cover also affects shipping routes through the polar regions.
(0 - 1)  
rsn 33 Snow density This parameter is the mass of snow per cubic metre in the snow layer.

The ECMWF Integrated Forecast System (IFS) model represents snow as a single additional layer over the uppermost soil level. The snow may cover all or part of the grid box.

See further information on snow in the IFS.
kg m**-3  
sst 34 Sea surface temperature This parameter is the temperature of sea water near the surface.

This parameter is taken from various providers, who process the observational data in different ways. Each provider uses data from several different observational sources. For example, satellites measure sea surface temperature (SST) in a layer a few microns thick in the uppermost mm of the ocean, drifting buoys measure SST at a depth of about 0.2-1.5m, whereas ships sample sea water down to about 10m, while the vessel is underway. Deeper measurements are not affected by changes that occur during a day, due to the rising and setting of the Sun (diurnal variations).

Sometimes this parameter is taken from a forecast made by coupling the NEMO ocean model to the ECMWF Integrated Forecasting System. In this case, the SST is the average temperature of the uppermost metre of the ocean and does exhibit diurnal variations.

See further documentation .

This parameter has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.
K  
swvl1 39 Volumetric soil water layer 1 This parameter is the volume of water in soil layer 1 (0 - 7cm, the surface is at 0cm).

The ECMWF Integrated Forecasting System model has a four-layer representation of soil:
Layer 1: 0 -7cm 
Layer 2: 7 -21cm 
Layer 3: 21-72cm
Layer 4: 72-189cm

The volumetric soil water is associated with the soil texture (or classification), soil depth, and the underlying groundwater level.
m**3 m**-3  
swvl2 40 Volumetric soil water layer 2 This parameter is the volume of water in soil layer 2 (7 - 21cm, the surface is at 0cm).

The ECMWF Integrated Forecasting System model has a four-layer representation of soil:
Layer 1: 0 -7cm 
Layer 2: 7 -21cm 
Layer 3: 21-72cm
Layer 4: 72-189cm

The volumetric soil water is associated with the soil texture (or classification), soil depth, and the underlying groundwater level.
m**3 m**-3  
swvl3 41 Volumetric soil water layer 3 This parameter is the volume of water in soil layer 3 (21 - 72cm, the surface is at 0cm).

The ECMWF Integrated Forecasting System model has a four-layer representation of soil:
Layer 1: 0 -7cm 
Layer 2: 7 -21cm 
Layer 3: 21-72cm
Layer 4: 72-189cm

The volumetric soil water is associated with the soil texture (or classification), soil depth, and the underlying groundwater level.
m**3 m**-3  
swvl4 42 Volumetric soil water layer 4 This parameter is the volume of water in soil layer 4 (72 - 189cm, the surface is at 0cm).

The ECMWF Integrated Forecasting System model has a four-layer representation of soil:
Layer 1: 0 -7cm 
Layer 2: 7 -21cm 
Layer 3: 21-72cm
Layer 4: 72-189cm

The volumetric soil water is associated with the soil texture (or classification), soil depth, and the underlying groundwater level.
m**3 m**-3  
10fg 49 10 metre wind gust since previous post-processing Maximum 3 second wind at 10 m height as defined by WMO.

Parametrization represents turbulence only before 01102008; thereafter effects of convection are included. The 3 s gust is computed every time step and and the maximum is kept since the last postprocessing.
m s**-1  
cape 59 Convective available potential energy This is an indication of the instability (or stability) of the atmosphere and can be used to assess the potential for the development of convection, which can lead to heavy rainfall, thunderstorms and other severe weather.

In the ECMWF Integrated Forecasting System (IFS), CAPE is calculated by considering parcels of air departing at different model levels below the 350 hPa level. If a parcel of air is more buoyant (warmer and/or with more moisture) than its surrounding environment, it will continue to rise (cooling as it rises) until it reaches a point where it no longer has positive buoyancy. CAPE is the potential energy represented by the total excess buoyancy. The maximum CAPE produced by the different parcels is the value retained.

Large positive values of CAPE indicate that an air parcel would be much warmer than its surrounding environment and therefore, very buoyant. CAPE is related to the maximum potential vertical velocity of air within an updraft; thus, higher values indicate greater potential for severe weather. Observed values in thunderstorm environments often may exceed 1000 joules per kilogram (J kg-1), and in extreme cases may exceed 5000 J kg-1.

The calculation of this parameter assumes: (i) the parcel of air does not mix with surrounding air; (ii) ascent is pseudo-adiabatic (all condensed water falls out) and (iii) other simplifications related to the mixed-phase condensational heating.
J kg**-1  
tclw 78 Total column cloud liquid water Vertical integral of cloud liquid water content kg m**-2  
tciw 79 Total column cloud ice water Vertical integral of cloud ice water content kg m**-2  
mx2t6 121 Maximum temperature at 2 metres in the last 6 hours - K  
mn2t6 122 Minimum temperature at 2 metres in the last 6 hours - K  
z 129 Geopotential This parameter is the gravitational potential energy of a unit mass, at a particular location, relative to mean sea level. It is also the amount of work that would have to be done, against the force of gravity, to lift a unit mass to that location from mean sea level.

The geopotential height can be calculated by dividing the geopotential by the Earth's gravitational acceleration, g (=9.80665 m s-2). The geopotential height plays an important role in synoptic meteorology (analysis of weather patterns). Charts of geopotential height plotted at constant pressure levels (e.g., 300, 500 or 850 hPa) can be used to identify weather systems such as cyclones, anticyclones, troughs and ridges.

At the surface of the Earth, this parameter shows the variations in geopotential (height) of the surface, and is often referred to as the orography.
m**2 s**-2  
tcw 136 Total column water This parameter is the sum of water vapour, liquid water, cloud ice, rain and snow in a column extending from the surface of the Earth to the top of the atmosphere. In old versions of the ECMWF model (IFS), rain and snow were not accounted for. kg m**-2  
tcwv 137 Total column water vapour Vertically integrated water vapour kg m**-2  
stl1 139 Soil temperature level 1 This parameter is the temperature of the soil in layer 1 (0 - 7cm, the surface is at 0cm).

The ECMWF Integrated Forecasting System model has a four-layer representation of soil:
Layer 1: 0 -7cm
Layer 2: 7 -21cm
Layer 3: 21-72cm
Layer 4: 72-189cm 

Soil temperature is set at the middle of each layer, and heat transfer is calculated at the interfaces between them. It is assumed that there is no heat transfer out of the bottom of the lowest layer.

This parameter has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.

See further information.
K  
sd 141 Snow depth This parameter is the depth of snow from the snow-covered area of a grid box.

Its units are metres of water equivalent, so it is the depth the water would have if the snow melted and was spread evenly over the whole grid box. The ECMWF Integrated Forecast System represents snow as a single additional layer over the uppermost soil level. The snow may cover all or part of the grid box.

See further information.
m of water equivalent  
msl 151 Mean sea level pressure This parameter is the pressure (force per unit area) of the atmosphere adjusted to the height of mean sea level.

t is a measure of the weight that all the air in a column vertically above the area of Earth's surface would have at that point, if the point were located at the mean sea level. It is calculated over all surfaces - land, sea and in-land water.

Maps of mean sea level pressure are used to identify the locations of low and high pressure systems, often referred to as cyclones and anticyclones. Contours of mean sea level pressure also indicate the strength of the wind. Tightly packed contours show stronger winds.

The units of this parameter are pascals (Pa). Mean sea level pressure is often measured in hPa and sometimes is presented in the old units of millibars, mb (1 hPa = 1 mb = 100 Pa).
Pa  
blh 159 Boundary layer height This parameter is the depth of air next to the Earth's surface which is most affected by the resistance to the transfer of momentum, heat or moisture across the surface.

The boundary layer height can be as low as a few tens of metres, such as in cooling air at night, or as high as several kilometres over the desert in the middle of a hot sunny day. When the boundary layer height is low, higher concentrations of pollutants (emitted from the Earth's surface) can develop. 

The boundary layer height calculation is based on the bulk Richardson number (a measure of the atmospheric conditions) following the conclusions of a 2012 review. See further information.
m  
tcc 164 Total cloud cover This parameter is the proportion of a grid box covered by cloud. Total cloud cover is a single level field calculated from the cloud occurring at different model levels through the atmosphere. Assumptions are made about the degree of overlap/randomness between clouds at different heights.

Cloud fractions vary from 0 to 1.
(0 - 1)  
10u 165 10 metre U wind component This parameter is the eastward component of the 10m wind. It is the horizontal speed of air moving towards the east, at a height of ten metres above the surface of the Earth, in metres per second.

Care should be taken when comparing this parameter with observations, because wind observations vary on small space and time scales and are affected by the local terrain, vegetation and buildings that are represented only on average in the ECMWF Integrated Forecasting System.

This parameter can be combined with the V component of 10m wind to give the speed and direction of the horizontal 10m wind.
m s**-1  
10v 166 10 metre V wind component This parameter is the northward component of the 10m wind. It is the horizontal speed of air moving towards the north, at a height of ten metres above the surface of the Earth, in metres per second.

Care should be taken when comparing this parameter with observations, because wind observations vary on small space and time scales and are affected by the local terrain, vegetation and buildings that are represented only on average in the ECMWF Integrated Forecasting System.

This parameter can be combined with the U component of 10m wind to give the speed and direction of the horizontal 10m wind.
m s**-1  
2t 167 2 metre temperature This parameter is the temperature of air at 2m above the surface of land, sea or in-land waters.

2m temperature is calculated by interpolating between the lowest model level and the Earth's surface, taking account of the atmospheric conditions. See further information .

This parameter has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.
K  
2d 168 2 metre dewpoint temperature This parameter is the temperature to which the air, at 2 metres above the surface of the Earth, would have to be cooled for saturation to occur.

It is a measure of the humidity of the air. Combined with temperature and pressure, it can be used to calculate the relative humidity.

2m dew point temperature is calculated by interpolating between the lowest model level and the Earth's surface, taking account of the atmospheric conditions. See further information.This parameter has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.
K  
stl2 170 Soil temperature level 2 This parameter is the temperature of the soil in layer 2 (7 - 21cm, the surface is at 0cm).

The ECMWF Integrated Forecasting System model has a four-layer representation of soil:
Layer 1: 0 -7cm
Layer 2: 7 -21cm
Layer 3: 21-72cm
Layer 4: 72-189cm 

Soil temperature is set at the middle of each layer, and heat transfer is calculated at the interfaces between them. It is assumed that there is no heat transfer out of the bottom of the lowest layer.

This parameter has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.

See further information.
K  
lsm 172 Land-sea mask This parameter is the proportion of land, as opposed to sea or in-land waters, in a grid box.

This parameter has values ranging between zero and one and is dimensionless.

Grid boxes in the ECWMF Integrated Forecast System with a value above 0.5 are treated as wholly land (and inland waters). Those with a value below 0.5 are treated as ocean.
(0 - 1)  
mx2t 201 Maximum temperature at 2 metres since previous post-processing This parameter is the highest temperature of air at 2m above the surface of land, sea or in-land waters since the parameter was last archived in a particular forecast.

2m temperature is calculated by interpolating between the lowest model level and the Earth's surface, taking account of the atmospheric conditions. See further information .

This parameter has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.
K  
mn2t 202 Minimum temperature at 2 metres since previous post-processing This parameter is the lowest temperature of air at 2m above the surface of land, sea or in-land waters since the parameter was last archived in a particular forecast.

2m temperature is calculated by interpolating between the lowest model level and the Earth's surface, taking account of the atmospheric conditions. See further information .

This parameter has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.
K  
10si 207 10 metre wind speed This parameter is the horizontal speed of the wind, or movement of air, at a height of ten metres above the surface of the Earth. The units of this parameter are metres per second.

Care should be taken when comparing this parameter with observations, because wind observations vary on small space and time scales and are affected by the local terrain, vegetation and buildings that are represented only on average in the ECMWF Integrated Forecasting System.

The eastward and northward components of the horizontal wind at 10m are also available as parameters.
m s**-1  
stal1 171139 Soil temperature anomaly level 1 - K  
~ 172142 Stratiform precipitation (Large-scale precipitation) - m s**-1  
cprate 172143 Convective precipitation - m s**-1  
~ 172144 Snowfall (convective + stratiform) - m of water equivalent s**-1  
~ 172146 Surface sensible heat flux - W m**-2  
~ 172147 Surface latent heat flux - W m**-2  
~ 172169 Surface solar radiation downwards - W m**-2  
~ 172175 Surface thermal radiation downwards - W m**-2  
~ 172176 Surface solar radiation - W m**-2  
~ 172177 Surface thermal radiation - W m**-2  
~ 172178 Top solar radiation - W m**-2  
~ 172179 Top thermal radiation - W m**-2  
ewssra 172180 East-West surface stress rate of accumulation - N m**-2  
nsssra 172181 North-South surface stress rate of accumulation - N m**-2  
erate 172182 Evaporation - m of water s**-1  
~ 172189 Sunshine duration - ~  
tprate 172228 Total precipitation - m s**-1  
sundara 173189 Sunshine duration anomalous rate of accumulation - dimensionless  
100u 228246 100 metre U wind component - m s**-1  
100v 228247 100 metre V wind component - m s**-1  

VI-iii-b: Weekly means of individual ensemble member forecasts - Pressure levels

Available at 1000, 925, 850, 700, 500, 400, 300, 200, 100, 50, 20 hPa unless otherwise specified.

Short Name ID Long Name Description Units Additional information
strf 1 Stream function - m**2 s**-1  
vp 2 Velocity potential - m**2 s**-1  
t 130 Temperature This parameter is the temperature in the atmosphere.

It has units of kelvin (K). Temperature measured in kelvin can be converted to degrees Celsius (°C) by subtracting 273.15.

This parameter is available on multiple levels through the atmosphere. More information about availability here.
K  
u 131 U component of wind This parameter is the eastward component of the wind. It is the horizontal speed of air moving towards the east, in metres per second. A negative sign thus indicates air movement towards the west.

This parameter can be combined with the V component of wind to give the speed and direction of the horizontal wind.
m s**-1  
v 132 V component of wind This parameter is the northward component of the wind. It is the horizontal speed of air moving towards the north, in metres per second. A negative sign thus indicates air movement towards the south.

This parameter can be combined with the U component of wind to give the speed and direction of the horizontal wind.
m s**-1  
gh 156 Geopotential Height Geopotential divided by a constant value of g = 9.80665 gpm  

VI-iv: Weekly mean anomalies of individual ensemble member forecasts

Base time 00UTC only

Forecast ranges

2 runs (Monday and Thursday), four 7-day ranges per run

  Forecast time ranges Resolution
Monday

0-168/168-336/336-504/504-672

  • 0.4° x 0.4° lat/long grid or any multiple thereof (global or sub-area)
  • On model (Octahedral) O320 grid (global or sub-area)
  • Spectral components (TCO319) for upper-air fields (global area only)
Thursday

96-264/264-432/432-600/600-768

VI-iv-a: Weekly mean anomalies of individual ensemble member forecasts - Single level

Short Name ID Long Name Description Units Additional information
z 129 Geopotential This parameter is the gravitational potential energy of a unit mass, at a particular location, relative to mean sea level. It is also the amount of work that would have to be done, against the force of gravity, to lift a unit mass to that location from mean sea level.

The geopotential height can be calculated by dividing the geopotential by the Earth's gravitational acceleration, g (=9.80665 m s-2). The geopotential height plays an important role in synoptic meteorology (analysis of weather patterns). Charts of geopotential height plotted at constant pressure levels (e.g., 300, 500 or 850 hPa) can be used to identify weather systems such as cyclones, anticyclones, troughs and ridges.

At the surface of the Earth, this parameter shows the variations in geopotential (height) of the surface, and is often referred to as the orography.
m**2 s**-2  
lsm 172 Land-sea mask This parameter is the proportion of land, as opposed to sea or in-land waters, in a grid box.

This parameter has values ranging between zero and one and is dimensionless.

Grid boxes in the ECWMF Integrated Forecast System with a value above 0.5 are treated as wholly land (and inland waters). Those with a value below 0.5 are treated as ocean.
(0 - 1)  
rsna 171033 Snow density anomaly - kg m**-3  
mx2t6a 171121 Maximum temperature at 2 metres in the last 6 hours anomaly - K  
mn2t6a 171122 Minimum temperature at 2 metres in the last 6 hours anomaly - K  
stal1 171139 Soil temperature anomaly level 1 - K  
sda 171141 Snow depth anomaly - m of water equivalent  
msla 171151 Mean sea level pressure anomaly - Pa  
tcca 171164 Total cloud cover anomaly - (0 - 1)  
10ua 171165 10 metre U wind component anomaly - m s**-1  
10va 171166 10 metre V wind component anomaly - m s**-1  
2ta 171167 2 metre temperature anomaly - K  
2da 171168 2 metre dewpoint temperature anomaly - K  
sfara 173144 Snowfall (convective + stratiform) anomalous rate of accumulation - m of water equivalent s**-1  
sundara 173189 Sunshine duration anomalous rate of accumulation - dimensionless  
tpara 173228 Total precipitation anomalous rate of accumulation - m s**-1  

VI-iv-b: Weekly mean anomalies of individual ensemble member forecasts - Pressure Levels

Available at 1000, 925, 850, 700, 500, 400, 300, 200 hPa unless otherwise specified.

Short Name ID Long Name Description Units Additional information
strf 1 Stream function - m**2 s**-1  
vp 2 Velocity potential - m**2 s**-1  
vpota 171002 Velocity potential anomaly - m**2 s**-1  
za 171129 Geopotential anomaly - m**2 s**-2  
ta 171130 Temperature anomaly - K  
ua 171131 U component of wind anomaly - m s**-1  
va 171132 V component of wind anomaly - m s**-1  
qa 171133 Specific humidity anomaly - kg kg**-1  

VI-v: Individual forecast runs (daily real-time and re-forecast products)

VI-v-a: Individual forecast runs - Single level

Forecast ranges & resolution

  Forecast time step Base times Resolution
T+0h to T+360h 6-hourly 00 UTC
  • 0.2° x 0.2° lat/long grid or any multiple thereof (global or sub-area)
  • On model (Octahedral) O640 grid (global or sub-area)
  • Spectral components (TCO639) for upper-air fields (global area only)
T+366h to T+1104h 6-hourly 00 UTC
  • 0.4° x 0.4° lat/long grid or any multiple thereof (global or sub-area)
  • On model (Octahedral) O320 grid (global or sub-area)
  • Spectral components (TCO319) for upper-air fields (global area only)
Short name Long name Description Unit Id Additional information
10U 10 metre U-velocity - m s-1 165  
10V 10 metre V-velocity - m s-1 166  
10FG6 10 metre wind gust in the last 6 hours - m/s 123  
100U 100 metre U-velocity - m s-1 228246  
100V 100 metre V-velocity - m s-1 228247  
2D 2 metre dewpoint temperature - K 168  
2T 2 metre temperature - K 167  
CP Convective precipitation Precipitation from updraughts in the convection scheme. Accumulated field. m 143  
E Evaporation Moisture flux from the surface into the atmosphere. Accumulated field (by model convention downward fluxes are positive). m of water equivalent 182  
EWSS Eastward turbulent surface stress Eastward surface stress due to turbulent processes. Accumulated field. Nm**-2 180  
LSM (inv) Land/sea mask Fractional land cover (model uses 0.m s**-1 as threshold for mask) (0 - 1) 172 if requested, these parameters can be provided free of charge once with every forecast dissemination
MX2T6 Maximum temperature at 2m in the last 6 hours - K 121  
MSL Mean sea level pressure - Pa 151  
MN2T6 Minimum temperature at 2m in the last 6 hours - K 122  
NSSS Northward turbulent surface stress Northward surface stress due to turbulent processes. Accumulated field. Nm**-2 181  
Z (inv) Orography - m2 s-2 129 if requested, these parameters can be provided free of charge once with every forecast dissemination
SSTK Sea surface temperature Temperature of the sea water (bulk SST), as specified by external analysis (skin temperature is equal to bulk SST before 01/10/2008) K 34  
STRD Surface thermal radiation downwards   J m-2 175

re-forecasts are available only on 24 hourly steps

RSN Snow density   kg m-3 33  
SD Snow depth   m of water equivalent 141  
SF Snow fall (convective + stratiform)   m 144  
STL1 Soil temperature level 1 Top soil layer: 1-7 cm Soil temperature (ST) before 19930804 K 139  
STL2 Soil temperature level 2 Soil layer 2: 7-28 cm Deep soil temperature (DST) before 19930804 K 170  
STL3 Soil temperature level 3 Soil layer 3: 28-100 cm. Climatological deep soil temperature (CDST) before 19930804. K 183  
STL4 Soil temperature level 4 Layer 100-289 cm K 236  
SSRO Sub-surface runoff Deep soil drainage. Accumulated field m 9  
SUND Sunshine duration Time that radiation in the direction of the sun is above 120 W/m2. Accumulated field. s 189  
SP Surface pressure - Pa 134  
SRO Surface runoff Accumulated field m 8  
SSRD Surface solar radiation downwards Accumulated field J m-2 169  
TTR Top net thermal radiation Net thermal radiation at the top of the atmosphere. Accumulated field (by model convention downward fluxes are positive). J m-2 179  
TCC Total cloud cover Total cloud cover derived from model levels using the model's overlap assumption (0 -1) 164  
TCW Total column water Vertically integrated total water (vapour + cloud water + cloud ice) kg m**-2 136  
TP (tprate) Total precipitation Convective precipitation + stratiform precipitation (CP +LSP). Accumulated field. m 228172  
FDIR Total sky direct solar radiation at surface - J m-2 228021  
SWVL1 Volumetric soil water layer 1 Top soil layer: 0-7 cm m3 m-3  39  
SWVL2 Volumetric soil water layer 2 Soil layer 2: 7-28 cm m3 m-3 40  
SWVL3 Volumetric soil water layer 3  Soil layer 3: 28-100 cm m3 m-3 41  
SWVL4 Volumetric soil water layer 4 Soil layer 4: 100-289 cm m3 m-3 42  

VI-v-b: Individual forecast runs - Pressure levels

Available at 1000, 925, 850, 700, 500, 400, 300, 200 hPa unless otherwise specified.

Forecast ranges & resolution

  Forecast time step Base times Resolution
T+0h to T+360h 12-hourly 00 UTC
  • 0.2° x 0.2° lat/long grid or any multiple thereof (global or sub-area)
  • On model (Octahedral) O640 grid (global or sub-area)
  • Spectral components (TCO639) for upper-air fields (global area only)
T+372h to T+1104h 12-hourly 00 UTC
  • 0.4° x 0.4° lat/long grid or any multiple thereof (global or sub-area)
  • On model (Octahedral) O320 grid (global or sub-area)
  • Spectral components (TCO319) for upper-air fields (global area only)
MARS ABBREVIATION LONG NAME UNIT PARAMETER ID Additional information
GH Geopotential height m 156  
STRF Stream function m2 s-1 1  
T Temperature K 130  
U U-velocity m s-1 131  
V V-velocity m s-1 132  
VP Velocity potential m2 s-1 2  

VI-v-c: Individual forecast runs - Wave

Forecast ranges & resolution

  Forecast time step Base times Resolution
T+0h to T+360h 6-hourly 00 UTC
  • 0.25° x 0.25° lat/long grid or any multiple thereof (global or sub-area)
T+366h to T+1104h 6-hourly 00 UTC
  • 0.5° x 0.5° lat/long grid or any multiple thereof (global or sub-area)
MARS ABBREVIATION LONG NAME UNIT PARAMETER ID Additional information
SWH Significant height of combined wind waves and swell m 140229  

VI-vi: Probabilities (weekly products)

Product resolution

  • 0.4° x 0.4° lat/long grid or any multiple thereof (global or sub-area)
  • On model (Octahedral) O320 grid (global or sub-area)

Forecast ranges

2 runs (Monday and Thursday), four 7-day ranges per run

  Forecast time ranges Base times
Monday

0-168/168-336/336-504/504-672

00 UTC
Thursday

96-264/264-432/432-600/600-768

00 UTC

 VI-vi-a: Probabilities - weekly averaged

MARS ABBREVIATION LONG NAME UNIT PARAMETER ID Additional information
2TAG1 2 metre temperature anomaly of at least +1K % 131001  
2TAG2 2 metre temperature anomaly of at least +2K % 131002  
2TAG0 2 metre temperature anomaly of at least 0K % 131003  
2TALM1 2 metre temperature anomaly of at most -1K % 131004  
2TALM2 2 metre temperature anomaly of at most -2K % 131005  

VI-vi-B Probabilities - weekly accumulated

MARS ABBREVIATION LONG NAME UNIT PARAMETER ID Additional information
TPAG0 Total precipitation anomaly of at least 0 mm % 131008  
TPAG10 Total precipitation anomaly of at least 10 mm % 131007  
TPAG20 Total precipitation anomaly of at least 20 mm % 131006  

VI-vi-c: Probabilities - Probability distributions

Short Name ID Long Name Description Units Additional information
stl1p 131139 Soil temperature level 1 probability - %  
mslpp 131151 Mean sea level pressure probability - %  
2tp 131167 2 metre temperature probability - %  
tpp 131228 Total precipitation probability - %  
MARS ABBREVIATION LONG NAME UNIT PARAMETER ID Additional information
2T 2 metre temperature K 167 Quantile: 10:10, 1:10, 1:3, 1:5, 2:3, 2:5, 3:3, 3:5, 4:5, 5:5
TP (tprate) Total precipitation probability m 228131 Quantile: 10:10, 1:10, 1:3, 1:5, 2:3, 2:5, 3:3, 3:5, 4:5, 5:5

VI-vi-d: Probabilities - Probability boundaries

Quantile: 1:10, 1:3, 1:5, 2:3, 2:5, 3:5, 4:5, 9:10

Short Name ID Long Name Description Units Additional information
stal1 171139 Soil temperature anomaly level 1 - K  
msla 171151 Mean sea level pressure anomaly - Pa  
2ta 171167 2 metre temperature anomaly - K  
tpara 173228 Total precipitation anomalous rate of accumulation - m s**-1  
MARS ABBREVIATION LONG NAME UNIT PARAMETER ID Additional information
2T 2 metre temperature K 167 Quantile: 1:10, 1:3, 1:5, 2:3, 2:5, 3:5, 4:5, 9:10
TP (tprate) Total precipitation (anomalous rate of accumulation) m 228172 Quantile: 1:10, 1:3, 1:5, 2:3, 2:5, 3:5, 4:5, 9:10

 

Page last updated December 2016 (corrected March 2017)