AMMA DRY-RUN22 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 20050826-06UTC to 20050827-06UTC

Precipitation SYNOP reports

valid for 20050826-06UTC to 20050827-06UTC

24 hour cumulated FORECAST

(a)

(c)

(b)

(d)

24 hour accumulated rainfall (20050826 00UTC-24UTC) for:

(a) ARPEGE, (b) ARPEGE Tropiques, ( c ) ECMWF, (d) UK globalModel.

24 hour accumulated rainfall (20050826-06UTC to 20050827-06UTC)

for ECMWF model (Initialization: 20050821-12UTC).

24 hour accumulated rainfall (20050826-06UTC to 20050827-06UTC) for MESONH model.(Initialization: ECMWF 20050823-00UTC).

24 hour accumulated rainfall (20050826-06UTC to 20050827-06UTC) for

NOAA/NCEP model (Initialization: NCEP/GDAS 20050826-00UTC).

IPSL/LMDz GCM model at ~70km (forced by NCEP analysis)

24 hour accumulated rainfall (20050826-06UTC to 20050827-06UTC

ETA model (forced by NCEP analysis)

6 hour cumulated FORECAST

6-hour cumulated precipitation

INITIAL CONDITIONS: ALADIN NORAF 20050826 – 00UTC

00-06 06-12

12-18 18-24

INITIAL CONDITIONS: UK Global 20050825 – 18UTC

00-06 06-12

12-18 18-24

ECMWF Global model: 20050826

00-06 06-12

12-18 18-24

IPSL/LMDz GCM: 20050826

00-06 06-12

12-18 18-24

IPSL/LMDz GCM: 20050826 at 12UTC

20050823 06UTC-12UTC 20050823 12UTC-18UTC

20050823 18UTC-24UTC

INITIAL CONDITIONS:ECMWF 20050823 – 00UTC