THE BLACK FOREST STORM OF THE BLACK FOREST STORM OF 15 JULY 2007: NUMERICAL 15 JULY 2007: NUMERICAL

SIMULATION AND SENSITIVITY SIMULATION AND SENSITIVITY STUDIESSTUDIES

THE BLACK FOREST STORM OF THE BLACK FOREST STORM OF 15 JULY 2007: NUMERICAL 15 JULY 2007: NUMERICAL

SIMULATION AND SENSITIVITY SIMULATION AND SENSITIVITY STUDIESSTUDIES

Evelyne RichardEvelyne Richard11, Jean-Pierre , Jean-Pierre ChaboureauChaboureau11

Cyrille FlamantCyrille Flamant22 and Cédric and Cédric ChampollionChampollion33

1. Laboratoire d’Aérologie, CNRS/UPS Toulouse, 1. Laboratoire d’Aérologie, CNRS/UPS Toulouse, FranceFrance

2. LATMOS/IPSL, CRNS/UPMC, Paris, France2. LATMOS/IPSL, CRNS/UPMC, Paris, France3. Géosciences, Montpellier, France3. Géosciences, Montpellier, France

COPS IOP8b – 15 July 2007

(Courtesy of DLR)

> 60 dBz

12

km

Radar reflectivity : Time evolution of Radar reflectivity : Time evolution of the the

10 dBZ contour10 dBZ contour

Radar reflectivity : Time evolution of Radar reflectivity : Time evolution of the the

10 dBZ contour10 dBZ contour

Montancy radarMontancy radar Simulation (ECMWF)Simulation (ECMWF)

12:15 –13:0012:15 –13:0013:15 – 14:0013:15 – 14:0014:15 – 15:0014:15 – 15:0015:15 – 16:0015:15 – 16:00

Radar reflectivity : Time evolution of Radar reflectivity : Time evolution of the the

10 dBZ contour10 dBZ contour

Radar reflectivity : Time evolution of Radar reflectivity : Time evolution of the the

10 dBZ contour10 dBZ contour

Montancy radarMontancy radar Simulation (ARPEGE)Simulation (ARPEGE)

12:15 –13:0012:15 –13:0013:15 – 14:0013:15 – 14:0014:15 – 15:0014:15 – 15:0015:15 – 16:0015:15 – 16:00

Motivations and Motivations and outlinesoutlines

Motivations and Motivations and outlinesoutlines

The real time Meso-NH forecast of this event was The real time Meso-NH forecast of this event was surprisingly good … but surprisingly good … but

■ Is this good forecast obtained for the good reasons?Is this good forecast obtained for the good reasons?■ What makes the ARPEGE based forecast different? What makes the ARPEGE based forecast different?

CAPE / CIN

Surface conditions

Sensitivity tests

CAPECAPE MESO-NH / ECMWF

MESO-NH ARPEGE

11:00 UTC

14:00 UTC

CINCIN MESO-NH / ECMWF

MESO-NH / ARPEGE

11:00 UTC

14:00 UTC

KarlruheKarlruhe

MeiztreizheimMeiztreizheim

AchernAchern

HornisgrindeHornisgrinde

HeselbachHeselbach

BurnhauptBurnhaupt

TIME

6 KM

0 KM

Water vapor mixing ratio (g/kg)

OBS. ECMWF ARPEGE

KarlruheKarlruhe

MeiztreizheimMeiztreizheim

AchernAchern

HornisgrindeHornisgrinde

HeselbachHeselbach

BurnhauptBurnhaupt

TIME

6 KM

0 KM

OBS. ECMWF ARPEGE

Potential temperature (K)

Surface moisture analysis : 00UTCSurface moisture analysis : 00UTCSurface moisture analysis : 00UTCSurface moisture analysis : 00UTC

ECMWFECMWF ARPEGEARPEGE

Sensitivity testsSensitivity testsSensitivity testsSensitivity tests

■ ECMWF surface moisture reduced by 20% ECMWF surface moisture reduced by 20% ■ ECMWF surface moisture reduced by 50% ECMWF surface moisture reduced by 50%

Thermodynamical conditions

Convection

KarlruheKarlruhe

MeiztreizheimMeiztreizheim

AchernAchern

HornisgrindeHornisgrinde

HeselbachHeselbach

BurnhauptBurnhaupt

TIME

6 KM

0 KM

OBS. ECMWF ARPEGE

Potential temperature (K)

Water vapor mixing ratio @ 13 Water vapor mixing ratio @ 13 UTCUTC

Water vapor mixing ratio @ 13 Water vapor mixing ratio @ 13 UTCUTC

ControlControl ObservationObservation 20% reduction20% reduction

Water vapor mixing ratio @ 13 Water vapor mixing ratio @ 13 UTCUTC

Water vapor mixing ratio @ 13 Water vapor mixing ratio @ 13 UTCUTC

ObservationObservation 20% reduction20% reduction50% reduction50% reduction

Cloud top height (color) + Instant Cloud top height (color) + Instant precipitation (contour) @ 15 UTCprecipitation (contour) @ 15 UTCCloud top height (color) + Instant Cloud top height (color) + Instant precipitation (contour) @ 15 UTCprecipitation (contour) @ 15 UTC

ControlControl 20% reduction20% reduction 50% reduction50% reduction

Convection is strongly controlled by initial moisture conditions

Summary / Summary / ConclusionConclusionSummary / Summary / ConclusionConclusion

■ Convection is well captured by the ECMWF- based Meso-NH forecast although the PBL is too cold and too moist.

■ The PBL structure is more correct in the ARPEGE-based MESO-NH forecast but convection is over predicted.

■ There is a large discrepancy between ECMWF and ARPEGE surface moisture analysis

■ The sensitivity tests shows that the convection triggering is strongly controlled by the surface moisture conditions

■ Do we have enough data to validate the surface moisture conditions?

MESO-NH ForecastsMESO-NH ForecastsMESO-NH ForecastsMESO-NH Forecasts

3 domains (32, 8, and 2 km) with 2-way interaction. 30h forecast starting at 00 UTC from ECMWF analysis Mixed phase microphysics (including hail particles) No convection parameterization in the 2km-mesh model

16/07 06UTC16/07 06UTC

MNH-MNH-ECMECM

12UTC12UTC15/07 00UTC

MNH-MNH-ARPARP

MNH-ECMMNH-ECM Run starting from the ECMWF analysis and forced with ECMWF forecasts

MNH-ARPMNH-ARP: Run starting from the ARPEGE analysis and forced with ARPEGE forecasts

16UTC16UTC

Convection over the

Black-Forest

KarlruheKarlruhe

MeiztreizheimMeiztreizheim

AchernAchern

HornisgrindeHornisgrinde

HeselbachHeselbach

BurnhauptBurnhaupt

TIME

6 KM

0 KM

COR

Morning Morning Afternoon Afternoon Morning Morning Afternoon Afternoon

1000 m 1000 m

2000 m2000 m

Rv mod – 2g/kg

Squares : Rv obs ( 2 lidars + Do28)

Water vapor mixing ratio : 13:00 – 13:30 UTCWater vapor mixing ratio : 13:00 – 13:30 UTC

Lidar observationsLidar observations

Water vapor mixing ratio : 13:00 – 13:30 UTCWater vapor mixing ratio : 13:00 – 13:30 UTC

Meso-NH Forecast Lidar observationsMeso-NH Forecast Lidar observations

Upward motionUpward motionUpward motionUpward motion

Convergence > 0.5 10 -3 s-1 + streamlines

@1000m

Convergence > 0.5 10 -3 s-1 + streamlines

@1000m 11 UTC 12 UTC

13 UTC 14 UTC

Convergence > 0.5 10 -3 s-1 + streamlines @ the surface

Moisture supplyMoisture supplyMoisture supplyMoisture supply

Soundings (3 hourly)

Airborne lidar (Leandre II + DLR Dial)

In situ aircraft data (Dornier 28)

Soundings (3 hourly)

Airborne lidar (Leandre II + DLR Dial)

In situ aircraft data (Dornier 28)

Convergence line in the lee of the Feldberg:

Feldberg Radar 13:08 UTCFeldberg Radar 13:08 UTC

Doppler velocityDoppler velocityWind @ 900hPa Wind @ 900hPa Moisture @750hPa > 7g/kgMoisture @750hPa > 7g/kg

Meso-NH Forecast 13:00 UTCMeso-NH Forecast 13:00 UTC

Water vapor mixing ratio : 13:00 – 13:30 UTCWater vapor mixing ratio : 13:00 – 13:30 UTC

Meso-NH Forecast Meso-NH Forecast

Lidar observationsLidar observations

Observation / Observation / SimulationSimulation

Observation / Observation / SimulationSimulation

METEOSAT TB = 280 KMETEOSAT TB = 280 K

Observation / Observation / SimulationSimulation

Observation / Observation / SimulationSimulation

MONTANCY R = 1dBZ

MONTANCY R = 1dBZ

METEOSAT TB = 280 KMETEOSAT TB = 280 K