AMMA DRY-RUN 22 August – 2 September 2005 Comments from J-Ph Lafore (CNRM) and an example validation for 26/08/2005

Cases: an active period! Weak convective days –24, 27, 30 August Long-lived MCS events –27-30 August; –30 August – 3 Sept; –2 Sept. – 5 Sept Convection to N of Mali in 3 cases

General impressions Models struggle with convection even at 24 hours (no surprise) Generally harder to predict suppressed convection LAM not necessarily better at convective prediction than Global (but better structure) Active hurricanes downstream!!

OBSERVATIONS

NOAA-CPC Precipitation estimate valid UTC to UTC

Precipitation SYNOP reports valid for UTC to UTC

24 hour cumulated FORECAST

(a) (c) (b) (d) 24 hour accumulated rainfall ( UTC-24UTC) for: (a) ARPEGE, (b) ARPEGE Tropiques, ( c ) ECMWF, (d) UK globalModel.

24 hour accumulated rainfall ( UTC to UTC) for ECMWF model (Initialization: UTC).

24 hour accumulated rainfall ( UTC to UTC) for MESONH model.(Initialization: ECMWF UTC).

24 hour accumulated rainfall ( UTC to UTC) for NOAA/NCEP model (Initialization: NCEP/GDAS UTC).

IPSL/LMDz GCM model at ~70km (forced by NCEP analysis) 24 hour accumulated rainfall ( UTC to UTC ETA model (forced by NCEP analysis)

6 hour cumulated FORECAST

6-hour cumulated precipitation INITIAL CONDITIONS: ALADIN NORAF – 00UTC

INITIAL CONDITIONS: UK Global – 18UTC

ECMWF Global model:

IPSL/LMDz GCM:

IPSL/LMDz GCM: at 12UTC

UTC-12UTC UTC-18UTC UTC-24UTC INITIAL CONDITIONS: ECMWF – 00UTC