Verification of LAMI: QPF over northern Italy and vertical profiles Elena Oberto (*), Paolo Bertolotto (*), Massimo Milelli (*) (*) ARPA Piemonte, Torino, Italy

Objectives Verification of LAMI QPF: Verification of LAMI soundings: Italian data set situation Period considered for validation: June 2002- February 2003 We compare the average value of rain over different mesh size boxes (in each box there must be at least 2 station points) Verification of LAMI soundings: Period: December 2003 - February 2003 Cesana Pariol (1545 m) Cuneo Levaldigi (386 m)

The new radiosounding of Cesana Pariol (1545 m), placed in the Olympic area, is used to compare the observed and forecasted vertical profiles (at 00UTC every day) An other radiosounding in our region is placed near Cuneo Levaldigi Airport (installed in 1999, since 1 year it is a GTS station): we perform the same vertical profile verification to have a comparison with a station in a non-mountainous area. Mean error (BIAS) and Root Mean Square Error for each level (25hPa) of the vertical profiles (00UTC LAMI run for +24h and +48h forecast time) from Dec ‘02 to Feb ‘03. Cesana Pariol (45° N 6.8° E): station point 1545 m grid point 1970 m Cuneo Levaldigi (44.5° N 7.6° E): station point 386 m grid point 387 m !

Box subdivision

Situation of data set for Italy: data used data not yet useful data soon available

Main results 24h averaged scores for QPF 6h averaged scores for QPF (diurnal cycle and seasonal trend) Soundings profiles: temperature rh dew point temperature wind velocity

BIAS: average over boxes in 24h for LAMI 00UTC

ETS: average over boxes in 24h for LAMI 00UTC

6h seasonal trend

Comments LAMI bias is always > 1; better skills for the second 24h there is no variation of results with the mesh size the diurnal cycle is evident (worst results between 18-24UTC) and is influenced by the Autumn precipitation pattern The model is systematically more humid than the reality (from our experience: GME is more humid than ECMWF) It is also colder than observations, at least in the lower layers of the atmosphere There is a general slight degrade of the results in the second 24h There are great differences in the PBL region probably due to: wrong elevation of Cesana grid point in the model orography parameterisation problems in the PBL ?

ROC diagram: average over 0.5° boxes in 24h for LAMI00-LAMI12