Current status of SINFONY - the combination of Nowcasting and Numerical Weather Prediction on the convective scale at DWD

DWD's new Seamless INtegrated FOrecastiNg sYstem (SINFONY) is about to come to life in the next two years,
after 5 years of research and development.
For now, the system focuses on severe convective events in the very short time forecast range from minutes to 12~h.

There are different "optimal" forecast methods for different forecast lead times and different weather phenomena.
Focusing on precipitation and convective events up to some hours ahead, radar extrapolation techniques (Nowcasting)
show good skill up to about 2 h ahead (depending on the situation), while numerical weather prediction (NWP)
outperforms Nowcasting only at later hours. Ensembles of both Nowcasting and NWP help
to assess forecast uncertainties.
"Optimally" combining precipitation forecasts from Nowcasting and NWP
as function of lead time leads to the seamless forecasts of the SINFONY.

Different interdisciplinary teams work closely together in developing
a) radar Nowcasting ensembles for precipitation, reflectivity and convective cell objects,
b) a regional ICON-ensemble model with extensive data assimilation of high-resolution remote sensing data (3D radar volume scans of radial winds and reflectivity, cell objects, Meteosat VIS channels and lightning)
and hourly new rapid update cycle forecasts (SINFONY-RUC-EPS) on the km-scale,
c) optimal combinations of Nowcasting and NWP ensemble forecasts in observation space. Gridded combined precipitation and reflectivity ensembles are targeted towards hydrologic warnings. Combined Nowcasting- and NWP cell object ensembles help evolve DWD's warning process for convective events towards a flexible
"warn-on-objects".
d) systems for common Nowcasting and NWP verification of precipitation, reflectivity and objects.
   In particular the cell object based verification will provide new insights into the representation of deep convective cells in the model. 

For b), new innovative and efficient forward operators for radar volume scans and visible satellite data enable
direct operational assimilation of these data in an LETKF framework.
Advanced model physics (stochastic PBL scheme, 2-moment bulk cloud mircophysics) contribute to an improved forecast of convective clouds.

For c), the SINFONY-RUC-EPS outputs simulated reflectivity volume scan ensembles of the
entire German radar network every 5' online during its forecast runs.
Ensembles of composites and cell object tracks are generated
by the same compositing and cell detection- and tracking methods/software packages which are applied to the observations.

During the last year, all these methods have been further consolidated, and the RUC, along with some of the new nowcasting methods, has been run daily in a continuous test forecast mode.

This presentation will give a short overview on the activities of the last year and selected results of the test forecast mode.
Other presentations from SINFONY team members will give more details about the particular SINFONY components.