1. MAP and IMPROVE II Experimental Areas SHARE Workshop, Boulder, 5 May 2005

2. 2D Idealized WRF simulation of cross-barrier flow

3. 120 90 60 30 0 Distance (km) from S-Pol radar 1 2 3 4 5 6 Height (km) MAP IOP2b – 20 September 1999 3h MEAN S-Pol RADAR DATA REFLECTIVITY RADIAL VELOCITY FREQUENCY OCCURRENCE 54 44 34 24 14 4 -6 -16 -26 dBZ 36 30 24 18 12 6 0 -6 -12 m/s 16 14 12 10 8 6 4 2 0 % STABILITY FROM MILAN SOUNDING VERTICAL POINTING RADAR 0700 0720 0740 Time (UTC) 20 Sep REFLECTIVITY RADIAL VELOCITY 0 1 2 3 4 5 6 Height (km) 0 1 2 3 4 5 6 Dry snow (50 %) Wet snow (30 %) Graupel - Shaded

4. 120 90 60 30 0 Distance (km) from S-Pol radar 1 2 3 4 5 6 Height (km) MAP IOP2b – 20 September 1999 3h MEAN S-Pol RADAR DATA REFLECTIVITY RADIAL VELOCITY FREQUENCY OCCURRENCE 54 44 34 24 14 4 -6 -16 -26 dBZ 36 30 24 18 12 6 0 -6 -12 m/s 16 14 12 10 8 6 4 2 0 % STABILITY FROM MILAN SOUNDING VERTICAL POINTING RADAR 0700 0720 0740 Time (UTC) 20 Sep REFLECTIVITY RADIAL VELOCITY 0 1 2 3 4 5 6 Height (km) 0 1 2 3 4 5 6 Dry snow (50 %) Wet snow (30 %) Graupel - Shaded

5. 120 90 60 30 0 Distance (km) from S-Pol radar 1 2 3 4 5 6 Height (km) MAP IOP8 – 21 October 1999 3h MEAN S-Pol RADAR DATA REFLECTIVITY RADIAL VELOCITY FREQUENCY OCCURRENCE 54 44 34 24 14 4 -6 -16 -26 dBZ 36 30 24 18 12 6 0 -6 -12 m/s 16 14 12 10 8 6 4 2 0 % STABILITY FROM MILAN SOUNDING Dry snow (50 %) Wet snow (30 %) Graupel - Shaded Graupel and/or dry aggregates – Shaded VERTICAL POINTING RADAR REFLECTIVITY RADIAL VELOCITY 0600 0800 1000 1200 Time (UTC) 21 Oct 0 2 4 6 8 Height (km) 0 2 4 6 8 REFLECTIVITY RADIAL VELOCITY P3 RADIAL VELOCITY

6. 2D Idealized WRF simulation of cross-barrier flow CASE 11

7. 0 25 50 75 100 Distance (km) from S-Pol radar 1 2 3 4 5 6 Height (km) IMPROVE II CASE 11 – 13-14 December 2001 3h MEAN S-Pol RADAR DATA REFLECTIVITY RADIAL VELOCITY FREQUENCY OCCURRENCE 54 44 34 24 14 4 -6 -16 -26 dBZ 48 40 32 24 16 8 0 -8 -16 m/s 40 35 30 25 20 15 10 5 0 % STABILITY FROM UW SOUNDING Dry snow (50 %) Wet snow (30 %) Graupel - Shaded Graupel and/or dry aggregates – Shaded 1 2 3 4 5 6 VERTICAL POINTING RADAR 2300 0000 0100 0200 Time (UTC) 13-14 Dec 1 2 3 4 5 Height (km) 1 2 3 4 5 RADIAL VELOCITY (m/s) REFLECTIVITY (dBZ)

8. IMPROVE II CASE 11 – 13-14 December 2001 Ice particle images obtained by NOAA P3

9. IMPROVE II CASE 11 – 13-14 December 2001 Idealization

10. JAMES AND HOUZE ‘05 Synoptic Situations

11. JAMES AND HOUZE ‘05 Radar Climatology

12. What to investigate in SHARE? Processes affecting precipitation enhancement over windward slope More stable cases –Enhancement of low-level shear over windward slope in stable case –Turbulence in shear layer over the windward slope Buoyancy, shear, terrain –How turbulent overturning layer affects microphysical processes Aggregation, riming, coalescence –Temperature feedback Less stable cases –Enhanced lifting over small-scale individual peaks vs barrier scale Stable lifting at high Fr, or release of potential instability –Microphysical processes over individual peaks Riming, aggregation, coalescence

13. End

14. IMPROVE II CASE 11 – 13-14 December 2001 NOAA P3 aircraft tail radar data

15. IMPROVE II CASE 11 – 13-14 December 2001 Upstream sounding used in simulation

16. Upstream-upslope rain gauge comparison SalemLittle Meadows TOTALS Salem: 10.24” Little Meadows: 30.50”