The D-Phase MicroPEPS is a LAF-Ensemble (lagged average forecast) that is based upon 5 different high resolution models: COSMOCH2 LMK AROME CMCGEMH ISACMOL2 The individual members can be found in the respective experiments 'dphase_*' in this data base. As time lagged forecasts the initialisation times t-3h and t-6h relative to the reference time t are incorporated. In a maximum the MicroPEPS might have 9 members (COSMOCH2: 3, LMK: 3, AROME: 1, CMCGEMH: 1, ISACMOL: 1). While COSMOCH2 and LMK generate new forecasts every 3 hours the other models run less frequently. In the 6 hour MicroPEPS time window AROME, CMCGEMH and ISACMOL provide one run each. During operation the ensemble size might change due to the availability of the forecasts. The MicroPEPS uses equal weights for averaging its members. The MicroPEPS generates probability forecasts by interpreting the overlapping areas of the single forecasts as members of a local ensemble. Due to the different domains of the deterministic models the size of the ensemble depends on location. Hence the quality of the forecasted probability distributions varies over the domain. There will be four runs a day at 0, 6, 12 and 18 UTC. Grid description: CDOM: xfirst: 6.0 yfirst: 47.0 xsize: 168.0 ysize: 151.0 xinc: 0.03 yinc: 0.02 xnpole: 0.0 ynpole: 0.0 DDOM: xfirst: 2.0 yfirst: 43.0 xsize: 535.0 ysize: 351.0 xinc: 0.03 yinc: 0.02 xnpole: 0.0 ynpole: 0.0

The SRNWP-PEPS consists of 21 different operational limited area models: Weather Service / Limited Area Model / Resolution [km] / Coupling Model / Forcast Period / Time Interval [h] / Main Run [UTC] Denmark HIRLAM 16 ECMWF +60h 1 0, 6, 12, 18 Finland HIRLAM 22 ECMWF +54h 1 0, 6, 12, 18 Ireland HIRLAM 16 ECMWF +48h 3 0, 6, 12, 18 Netherlands HIRLAM 22 ECMWF +48h 1 0, 6, 12, 18 Spain HIRLAM 18 ECMWF +48h 1 0, 6, 12, 18 Norway HIRLAM 22 ECMWF +30h 1 0, 12 Sweden I HIRLAM 11 ECMWF +48h 3 0, 6, 12, 18 Sweden II HIRLAM 22 ECMWF +48h 3 0, 6, 12, 18 Belgium ALADIN 15 ARPEGE +60h 1 0, 12 Austria ALADIN_A 9.6 ARPEGE +48h 1 0, 12 France ALADIN_F 11 ARPEGE +48h 3 0, 12 Croatia ALADIN_L 8.9 ARPEGE +48h 3 0, 12 Czech Rep. ALADIN_L 11 ARPEGE +48h 1 0, 12 Hungary ALADIN_L 11 ARPEGE +48h 1 0, 12 Slovakia ALADIN_L 11 ARPEGE +48h 3 0, 12 Slovenia ALADIN_L 9.5 ARPEGE +48h 3 0, 12 United Kingdom UKMO-LAM 12 UM global +48h 3 0, 6, 12, 18 Germany LME 7 GME +78h 1 0, 12 // Germany LME 7 GME +48h 1 6, 18 Switzerland aLMo 7 ECMWF +72h 1 0, 12 Italy EuroLM 7 EuroHRM +60h 3 0, 12 Poland LM 14 GME +72h 3 0, 12 The relation between these models and the numbers of the SRNWP PEPS ensemble is anonymous. The SRNWP-PEPS generates probability forecasts by interpreting the overlapping areas of the single forecasts as members of a local ensemble. Due to the different domains of the deterministic models the size of the ensemble depends on location. Hence the quality of the forecasted probability distributions varies over the PEPS domain. THE PLEV data set could not be provided for PEPS. Grid description: xsize,ysize,xinc, yinc differ for ensemble members (see datasets) CDOM: xfirst: 6.0 yfirst: 47.0 xnpole: 0.0 ynpole: 0.0 DDOM: xfirst: 2.0 yfirst: 43.0 xnpole: 0.0 ynpole: 0.0

COSMO-SREPS (csreps) is a high-resolution ensemble system for the short-range (up to three days). The system consists of 16 integrations of the non-hydrostatic limited-area model COSMO. The model is run at about 10 km of horizontal resolution, with 40 levels in the vertical. The ensemble is generated by taking into account different sources of forecast errors, in order to describe the uncertainty affecting the scales of interest in the high-resolution weather forecast at the considered time range. Initial and boundary conditions perturbations are provided by some members of the Multi-Analysis Multi-Boundary SREPS system of INM: the 10-km COSMO runs of COSMO-SREPS are driven by the four lower resolution (25 km) COSMO runs provided by INM, nested on four different global models (IFS, GME, NCEP, UM) which use independent analyses. Each of the four 25-km COSMO run provides initial and boundary conditions (3-hourly) to four 10-km COSMO runs, which are differentiated by applying different model perturbations. Four parameters of the schemes used for the parameterisation of the sub-grid processes are randomly changed, within their range of variability, in the ensemble members. Grid description: DDOM: xfirst: -6.02 yfirst: -7.0 xsize: 135.0 ysize: 83.0 xinc: 0.09 yinc: 0.09 xnpole: 190.0 ynpole: 40.0

cleps stands for COSMO-LEPS, the Limited-area Ensemble Prediction System implemented and developed by ARPA-SIM in the framework of COSMO consortium. This system is made up of 16 integrations with the non-hydrostatic limited-area model COSMO (formerly known as Lokal Modell). The 16 integrations takes initial and boundary conditions from 16 selected members of ECMWF EPS; the following prodedure is used to select EPS members: 1) Two successive runs of ECMWF EPS (starting at 00 and 12UTC) are considered; since each EPS set is composed of 51 integrations, 102 members are 2) a clustering algorithm is applied to construct 16 clusters (of different population); the clustering variables are Z,U,V,Q at 500, 700, 850 hPa at +96, +120 fcst steps; the clustering domain is 30-60N, 10W-30E. 3) within each cluster a representative member (RM) is selected on the basis of the same variables used for the clustering; 4) 16 RMs are selected; 5) each RM provides both initial and boundary conditions to the limited-area integrations with the COSMO model, which is run 16 times; 6) the limited-area runs constitute COSMO-LEPS Each limited-area runs has the following features: start once a day at 12UTC; hor. res. 10 km; vert. res. 40 ML; fcst length: 132h; post-proc frequency: 3h The integration domain cover the whole Central and Southern Europe, although, for D-PHASE, only a subdomain is delivered. Grid description: DDOM: xfirst: -6.02 yfirst: -7.0 xsize: 135.0 ysize: 83.0 xinc: 0.09 yinc: 0.09 xnpole: 190.0 ynpole: 40.0

INMSREPS is 20 Member Multi-Model, Multi-Boundaries on 0.25 degree horizontal resolution with 40 vertical levels running twice a dayat 00 and 12 UTC. Forecast from HH+00h upto HH+72 h (with 6hourly forecast output). The 20 members are labeled with abbreviations, which denote the combination between limited area model (LAM)(first character) and global model condition (the next two characters): LAMs: H means HRM, I means HIRLAM, M means MM5, L means Lokal Model (COSMO) and U means Unified Model. GLOBAL CONDITIONS: AV means GFS (AVN), EC means ECMWF, GM means GME, UK means UKMO. This results in the following combinations: HAV,HEC,HGM,HUK,IAV,IEC,IGM,IUK,MAV,MEC,MGM,MUK,LAV,LEC,LGM,LUK,UAV,UEC,UGM,UUK. The 20 ensemble members are interpolated to a common verification area with 0.25 degree horizontal grid resolution, there is no FIX data set for this system. Grid description: DDOM: xfirst: 2.0 yfirst: 43.0 xsize: 65.0 ysize: 29.0 xinc: 0.25 yinc: 0.25 xnpole: 0.0 ynpole: 0.0

dphase_prevah The hydrological model PREVAH is adopted for (ensemble) runoff forecasts for several basins in Switzerland and North Italy. Runoff nowcasting is driven by observed meteorology consisting of data from meteorological stations and operational radar precipitation data. Forecasts are computed with three deterministic NWP models and with one atmospheric ensemble predictions system (EPS). Principal investigators are the Institute for Atmospheric and Climate Sciences of the ETH (IAC_ETH) and the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL). Data providers: Observed meteorology: MeteoSwiss, WSL, IST-SUPSI Rainfall Radar: MeteoSwiss CLEPS, COSMOCH2 and COSMOCH7: MeteoSwiss MM5_15: FZK, IMK-IFU Observed discharge: Swiss Federal Office for Environment (FOEN), CONTICINO Basins: Verzasca_at_Lavertezzo, Ticino_at_Bellinzona, Maggia_at_Solduno, Tresa_at_Rocchetta, Toce_at_Candoglia, Ticino_at_Miorina, Thur_at_Andelfingen, Linth_at_Mollis Sub-Experiments: Runoff nowcasting, CLEPS, COSMOCH2 and COSMOCH7 at all basins MM5_15 and Rainradar only at Verzasca_at_Lavertezzo, Thur_at_Andelfingen, Linth_at_Mollis

COSMO-SREPS (csreps) is a high-resolution ensemble system for the short-range (up to three days). The system consists of 16 integrations of the non-hydrostatic limited-area model COSMO. The model is run at about 10 km of horizontal resolution, with 40 levels in the vertical. The ensemble is generated by taking into account different sources of forecast errors, in order to describe the uncertainty affecting the scales of interest in the high-resolution weather forecast at the considered time range. Initial and boundary conditions perturbations are provided by some members of the Multi-Analysis Multi-Boundary SREPS system of INM: the 10-km COSMO runs of COSMO-SREPS are driven by the four lower resolution (25 km) COSMO runs provided by INM, nested on four different global models (IFS, GME, NCEP, UM) which use independent analyses. Each of the four 25-km COSMO run provides initial and boundary conditions (3-hourly) to four 10-km COSMO runs, which are differentiated by applying different model perturbations. Four parameters of the schemes used for the parameterisation of the sub-grid processes are randomly changed, within their range of variability, in the ensemble members. Grid description: DDOM: xfirst: -6.02 yfirst: -7.0 xsize: 135.0 ysize: 83.0 xinc: 0.09 yinc: 0.09 xnpole: 190.0 ynpole: 40.0

The SRNWP-PEPS consists of 21 different operational limited area models: Weather Service / Limited Area Model / Resolution [km] / Coupling Model / Forcast Period / Time Interval [h] / Main Run [UTC] Denmark HIRLAM 16 ECMWF +60h 1 0, 6, 12, 18 Finland HIRLAM 22 ECMWF +54h 1 0, 6, 12, 18 Ireland HIRLAM 16 ECMWF +48h 3 0, 6, 12, 18 Netherlands HIRLAM 22 ECMWF +48h 1 0, 6, 12, 18 Spain HIRLAM 18 ECMWF +48h 1 0, 6, 12, 18 Norway HIRLAM 22 ECMWF +30h 1 0, 12 Sweden I HIRLAM 11 ECMWF +48h 3 0, 6, 12, 18 Sweden II HIRLAM 22 ECMWF +48h 3 0, 6, 12, 18 Belgium ALADIN 15 ARPEGE +60h 1 0, 12 Austria ALADIN_A 9.6 ARPEGE +48h 1 0, 12 France ALADIN_F 11 ARPEGE +48h 3 0, 12 Croatia ALADIN_L 8.9 ARPEGE +48h 3 0, 12 Czech Rep. ALADIN_L 11 ARPEGE +48h 1 0, 12 Hungary ALADIN_L 11 ARPEGE +48h 1 0, 12 Slovakia ALADIN_L 11 ARPEGE +48h 3 0, 12 Slovenia ALADIN_L 9.5 ARPEGE +48h 3 0, 12 United Kingdom UKMO-LAM 12 UM global +48h 3 0, 6, 12, 18 Germany LME 7 GME +78h 1 0, 12 // Germany LME 7 GME +48h 1 6, 18 Switzerland aLMo 7 ECMWF +72h 1 0, 12 Italy EuroLM 7 EuroHRM +60h 3 0, 12 Poland LM 14 GME +72h 3 0, 12 The relation between these models and the numbers of the SRNWP PEPS ensemble is anonymous. The SRNWP-PEPS generates probability forecasts by interpreting the overlapping areas of the single forecasts as members of a local ensemble. Due to the different domains of the deterministic models the size of the ensemble depends on location. Hence the quality of the forecasted probability distributions varies over the PEPS domain. THE PLEV data set could not be provided for PEPS. Grid description: xsize,ysize,xinc, yinc differ for ensemble members (see datasets) CDOM: xfirst: 6.0 yfirst: 47.0 xnpole: 0.0 ynpole: 0.0 DDOM: xfirst: 2.0 yfirst: 43.0 xnpole: 0.0 ynpole: 0.0

cleps stands for COSMO-LEPS, the Limited-area Ensemble Prediction System implemented and developed by ARPA-SIM in the framework of COSMO consortium. This system is made up of 16 integrations with the non-hydrostatic limited-area model COSMO (formerly known as Lokal Modell). The 16 integrations takes initial and boundary conditions from 16 selected members of ECMWF EPS; the following prodedure is used to select EPS members: 1) Two successive runs of ECMWF EPS (starting at 00 and 12UTC) are considered; since each EPS set is composed of 51 integrations, 102 members are 2) a clustering algorithm is applied to construct 16 clusters (of different population); the clustering variables are Z,U,V,Q at 500, 700, 850 hPa at +96, +120 fcst steps; the clustering domain is 30-60N, 10W-30E. 3) within each cluster a representative member (RM) is selected on the basis of the same variables used for the clustering; 4) 16 RMs are selected; 5) each RM provides both initial and boundary conditions to the limited-area integrations with the COSMO model, which is run 16 times; 6) the limited-area runs constitute COSMO-LEPS Each limited-area runs has the following features: start once a day at 12UTC; hor. res. 10 km; vert. res. 40 ML; fcst length: 132h; post-proc frequency: 3h The integration domain cover the whole Central and Southern Europe, although, for D-PHASE, only a subdomain is delivered. Grid description: DDOM: xfirst: -6.02 yfirst: -7.0 xsize: 135.0 ysize: 83.0 xinc: 0.09 yinc: 0.09 xnpole: 190.0 ynpole: 40.0

The D-Phase MicroPEPS is a LAF-Ensemble (lagged average forecast) that is based upon 5 different high resolution models: COSMOCH2 LMK AROME CMCGEMH ISACMOL2 The individual members can be found in the respective experiments 'dphase_*' in this data base. As time lagged forecasts the initialisation times t-3h and t-6h relative to the reference time t are incorporated. In a maximum the MicroPEPS might have 9 members (COSMOCH2: 3, LMK: 3, AROME: 1, CMCGEMH: 1, ISACMOL: 1). While COSMOCH2 and LMK generate new forecasts every 3 hours the other models run less frequently. In the 6 hour MicroPEPS time window AROME, CMCGEMH and ISACMOL provide one run each. During operation the ensemble size might change due to the availability of the forecasts. The MicroPEPS uses equal weights for averaging its members. The MicroPEPS generates probability forecasts by interpreting the overlapping areas of the single forecasts as members of a local ensemble. Due to the different domains of the deterministic models the size of the ensemble depends on location. Hence the quality of the forecasted probability distributions varies over the domain. There will be four runs a day at 0, 6, 12 and 18 UTC. Grid description: CDOM: xfirst: 6.0 yfirst: 47.0 xsize: 168.0 ysize: 151.0 xinc: 0.03 yinc: 0.02 xnpole: 0.0 ynpole: 0.0 DDOM: xfirst: 2.0 yfirst: 43.0 xsize: 535.0 ysize: 351.0 xinc: 0.03 yinc: 0.02 xnpole: 0.0 ynpole: 0.0