Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft

High pressure weatherSystem over the Alps for nearly three weeksin Sept. 1999

Sep.9. 00 UTC 500hPa geopotentialand surface pressure

Diurnal Mountain Winds

H

Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft

Time series of horizontal wind vector

Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft

Time series of virtual temperature and meridional wind component

-8

-4

0

4

0 0 time [UTC]

291

295

299

12 0

9/8 9/9 9/10 9/11 9/12 9/13 9/14/1999

640m

640m

1360m

12 12 12 12 120 0 0 0

up

valle

yd

ow

nva

lley

Tvi

r[K

]v

[m/s

]

N

S

Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft

-0,5

3 6 9 12 15 18 21 Zeit in UTC

-7,5

-6,5

-5,5

-4,5

-3,5

-2,5

-1,5

-0,5

0,5

1,5

2,5

3,5

4,5

100

500

1000

Bergwind

Talwind

N-S

Win

d-K

om

ponen

te(m

/s)

Ho

ehe

ueb

erG

r.(m

)

Berg-wind

N / S wind component – mean of Sep. 8. – 14.

S R S S

SouthNorth

South

Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft

MM5 Modell

4 Modell domains Δx, Δ y = 27km, 9km, 3km, 1km

39 sigma height levels 15m agl – 100hPa

42h simulation run 12 UTC 11. Sept. – 06 UTC 13. Sept.

Physical processes parameterized:

- Radiation RRTM scheme (Mlawer)

-boundary layer processes (Gayno Seaman scheme)

cloud microphysics simple scheme (Dudheim)

cumulus parameterization in outer domain (Zängl)

Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft

Pot. Temperature 12. Sep.

400

600

800

1.000

1.200

1.400

0 3 6 9 12 15 18

292

294

294

296

298

Time [UTC]

He

igh

t[m

]as

l

400

600

800

1.000

1.200

1.400

0 3 6 9 12 15 18

290

Time [UTC]

292

294

296

298

292

WTR Measurements NN5 Simulation

Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft

Time series of pot. Temperature in the Rhine Valley

Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft

N - S wind component Sep. 12.

WTR Measurements NN5 Simulation

Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft

Pot. Temperature @ 10m agl Sept. 12 6UTC 16UTC

W

V

D

F

Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft

Wind field at 180m AGL and vertical cross section of temperature and wind on 12. Sep 06 UTC

Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft

Wind field at 180m AGL and vertical cross section of temperature and wind on 12. Sep 16 UTC