Skip to main content
Log in

On the performance of the new NWP nowcasting system at the Danish Meteorological Institute during a heavy rain period

  • Original Paper
  • Published:
Meteorology and Atmospheric Physics Aims and scope Submit manuscript

Abstract

At the Danish Meteorological Institute, the NWP nowcasting system has been enhanced to include assimilation of 2D precipitation rates derived from weather radar observations. The assimilation is performed using a nudging-based technique. Here the rain rates are used to estimate the changes in the vertical profile of horizontal divergence needed to induce the observed rain rate. Verification of precipitation forecasts for a 17-day period in August 2010 based on the NWP nowcasting system is presented and compared to a reference without assimilation of precipitation data. In Denmark, this period was particularly rainy, with several heavy precipitation events. Three of these events are studied in detail. The verification is mainly based on scatter plots and fractions skill scores, which give scale-dependant indicators of the spatial skill of the forecasts. The study shows that the inclusion of precipitation observations has a positive impact on the spatial skill of the forecasts. This positive impact is the largest in the first hour, and then gradually decreases. On the average, the forecasts with assimilation of precipitation are skilful after 4 h on scales down to a few tens of kilometers. For the events studied, the assimilation improves the forecasted frequencies of heavy and light precipitation relative to the control, while there is some tendency to overpredict intermediate precipitation levels.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13

Similar content being viewed by others

Notes

  1. Referred to here as the resolution where the model produces skillful forecasts at a given lead time.

References

  • Abel SJ, Boutle IA (2012) An improved representation of the raindrop size distribution for single-moment microphysics schemes. Q J R Meteorol Soc 138:2151–2162

    Article  Google Scholar 

  • Battan LJ (1973) Radar observation of the atmosphere, vol 2. The University of Chicago Press, Chicago, pp 297–302

    Google Scholar 

  • Caumont O, Ducrocq V, Wattrelot E, Jaubert G, Pradier-Vabre S (2010) 1D+3Dvar assimilation of radar reflectivity data: a proof of concept. Tellus Ser A Dyn Meteorol Oceanogr 62:173–187

    Article  Google Scholar 

  • Caya A, Sun J, Snyder C (2005) A comparison between the 4dvar and the ensemble kalman filter techniques for radar data assimilation. Mon Weather Rev 133(11):3081–3094

    Article  Google Scholar 

  • Courtier P, Andersson E, Heckley W, Vasiljevic D, Hamrud M, Hollingsworth A, Rabier F, Fisher M, Pailleux J (1998) The ecmwf implementation of three-dimensional variational assimilation (3d-var). I: formulation. Q J R Meteorol Soc 124(550):1783–1807

    Google Scholar 

  • Dixon M, Wiener G (1993) Titan: thunderstorm identification, tracking, analysis, and nowcasting—a radar-based methodology. J Atmos Ocean Technol 10(6):785–797

    Article  Google Scholar 

  • Ebert EE, Wilson LJ, Brown BG, Nurmi P, Brooks HE, Bally J, Jaeneke M (2004) Verification of nowcasts from the wwrp sydney 2000 forecast demonstration project. Weather Forecast 19(1):73–96

    Article  Google Scholar 

  • Gao J, Xue M, Shapiro A, Droegemeier KK (1999) A variational method for the analysis of three-dimensional wind fields from two doppler radars. Mon Weather Rev 127(9):2128–2142

    Article  Google Scholar 

  • Gilleland E, Ahijevych DA, Brown BG, Ebert EE (2010) Verifying forecasts spatially. Bull Am Meteorol Soc 91(10):1365–1373

    Article  Google Scholar 

  • Golding BW (1998) NIMROD: a system for generating automated very short range forecasts. Meteorol Appl 5:1–16

    Article  Google Scholar 

  • Hong SY, Dudhia J (2012) Next-generation numerical weather prediction: bridging parameterization, explicit clouds, and large eddies. Bull Am Meteorol Soc 93(1):ES6–ES9

  • Jensen DG, Petersen C, Rasmussen MR (2014) Assimilation of radar-based nowcast into a HIRLAM NWP model. Meteorol Appl

  • Jones C, Macpherson B (1997) A latent heat nudging scheme for the assimilation of precipitation data into an operational mesoscale model. Meteorol Appl 4(3):269–277

    Article  Google Scholar 

  • Kalman RE et al (1960) A new approach to linear filtering and prediction problems. J Basic Eng 82(1):35–45

    Article  Google Scholar 

  • Korsholm US, Petersen C, Sass BH, Nielsen NW, Jensen D, Olsen B, Gill R, Vedel H (2015) A new approach for assimilation of 2D radar precipitation in a high-resolution NWP model. Meteorol Appl 22(1):48–59

    Article  Google Scholar 

  • Lilly DK (1990) Numerical prediction of thunderstorms—has its time come? Q J R Meteorol Soc 116(494):779–798

    Google Scholar 

  • Marshall JS, Palmer WMK (1948) The distribution of raindrops with size. J Meteorol 5(4):165–166

    Article  Google Scholar 

  • Marshall J, Hitschfeld W, Gunn K (1955) Advances in radar weather. Adv Geophys 2:1

    Article  Google Scholar 

  • Marshall JS, Ballantvne EH (1975) Weather surveillance radar. J Appl Meteorol 14(7):1317–1338

    Article  Google Scholar 

  • Molinari J, Dudek M (1992) Parameterization of convective precipitation in mesoscale numerical models: a critical review. Mon Weather Rev 120(2):326–344

    Article  Google Scholar 

  • Ninomiya K, Taira R, Ueno M, Kurihara K, Kudo T (1987) Mesoscale very short-range numerical prediction with dynamical initialization including condensation heating. ESA, Mesoscale Analysis and Forecasting, SP-282, pp 611–616

  • Parrish DF, Derber JC (1992) The national meteorological center’s spectral statistical-interpolation analysis system. Mon Weather Rev 120(8):1747–1763

    Article  Google Scholar 

  • Qiu CJ, Xu Q (1992) A simple adjoint method of wind analysis for single-Doppler data. J Atmos Ocean Technol 9(5):588–598

    Article  Google Scholar 

  • Rabier F, Järvinen H, Klinker E, Mahfouf JF, Simmons A (2000) The ecmwf operational implementation of four-dimensional variational assimilation. I: experimental results with simplified physics. Q J R Meteorol Soc 126(564):1143–1170

    Article  Google Scholar 

  • Roberts NM, Lean HW (2008) Scale-selective verification of rainfall accumulations from high-resolution forecasts of convective events. Mon Weather Rev 136(1):78–97

    Article  Google Scholar 

  • Roebber PJ, Schultz DM, Colle BA, Stensrud DJ (2004) Toward improved prediction: high-resolution and ensemble modeling systems in operations. Weather Forecast 19(5)

  • Sass BH, Petersen C (2002) Short range atmospheric forecasts using a nudging procedure to combine analyses of cloud and precipitation with a numerical forecast model. DMI

  • Shapiro A, Ellis S, Shaw J (1995) Single-doppler velocity retrievals with phoenix ii data: clear air and microburst wind retrievals in the planetary boundary layer. J Atmos Sci 52(9):1265–1287

    Article  Google Scholar 

  • Skamarock WC (2004) Evaluating mesoscale nwp models using kinetic energy spectra. Mon Weather Rev 132(12)

  • Sun J, Flicker DW, Lilly DK (1991) Recovery of three-dimensional wind and temperature fields from simulated single-Doppler radar data. J Atmos Sci 48(6):876–890

    Article  Google Scholar 

  • Sun J, Crook NA (1997) Dynamical and microphysical retrieval from doppler radar observations using a cloud model and its adjoint. part i: Model development and simulated data experiments. J Atmos Sci 54(12):1642–1661

    Article  Google Scholar 

  • Sun J, Crook NA (1998) Dynamical and microphysical retrieval from doppler radar observations using a cloud model and its adjoint. Part II: retrieval experiments of an observed florida convective storm. J Atmos Sci 55(5):835–852

    Article  Google Scholar 

  • Sun J (2005) Convective-scale assimilation of radar data: progress and challenges. Q J R Meteorol Soc 131(613):3439–3463

    Article  Google Scholar 

  • Sun J, Xue M, Wilson JW, Zawadzki I, Ballard SP, Onvlee-Hooimeyer J, Joe P, Barker DM, Li PW, Golding B et al (2014) Use of nwp for nowcasting convective precipitation: recent progress and challenges. Bull Am Meteorol Soc 95(3):409–426

    Article  Google Scholar 

  • Unden P, Rontu L, Järvinen H, Lynch P, Calvo J, Cats G, Cuxart J, Eerola K, Fortelius C, Garcia-Moya JA et al (2002) Hirlam-5 scientific documentation. http://www.hirlam.org

  • Wang H, Sun J, Zhang X, Huang X, Auligné T (2013) Radar data assimilation with WRF 4D-Var. Part I: system development and preliminary testing. Mon Weather Rev 141(7):2224–2244

    Article  Google Scholar 

  • Wattrelot E, Caumont O, Mahfouf JF (2014) Operational implementation of the 1D+3D-Var assimilation method of radar reflectivity data in the AROME model. Mon Weather Rev 142:1852–1873

    Article  Google Scholar 

Download references

Acknowledgments

This work was supported by the HydroCast project (hydrocast.dhigroup.com) funded partly by the Danish Council for Strategic Research under the Programme Commission on Sustainable Energy and Environment, and the OMOVAST project, funded partly by the Danish Ministry of Environment, under the Programme for Development and Demonstration Projects. The authors would like to express our gratitude for the constructive reviewer feedback. The first author would like to acknowledge DMI for funding the work which was carried out at the institute.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Bjarke Tobias Olsen.

Additional information

Responsible Editor: X.-Y. Huang.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Olsen, B.T., Korsholm, U.S., Petersen, C. et al. On the performance of the new NWP nowcasting system at the Danish Meteorological Institute during a heavy rain period. Meteorol Atmos Phys 127, 519–535 (2015). https://doi.org/10.1007/s00703-015-0388-y

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00703-015-0388-y

Keywords

Navigation