1. Real Time High-Resolution NWP @ McGill University J. Gyakum 1, R. McTaggart- Cowan 1, P. Sisson 2 1 McGill University 2 National Weather Service

2. Objectives Implementation of a real time MC2 system Data collection for stat- istical analysis and case studies Investigate impacts of high- resolution modelling on QPF and near-surface winds

3. Outline Need for mesoscale modelling Description of NWP system Validation case study (1 May 2002) Projected completion timeline

4. High Resolution (3km) Accurate topography Improved wind fields and fluxes Model terrain- induced confluence

5. Mesoscale Orography High resolution (6 km) Degraded resolution (~100 km)

6. Model Description MC2 version 4.9.3 Non-hydrostatic, semi- implicit time step, semi- Lagrangian advection Full physics version 3.72 Three one-way nest domains

7. Nesting Strategy 36km 12 km 3 km

8. Computational Platform NEC SX-5 supercomputer maintained by RPN/CMC 2x16 PE nodes 8G memory per PE (128 G/node) Theoretical peak performance 128 GFlop

9. Performance Timeline 0000 UTC0300 UTC0600 UTC0900 UTC CMC Regional Forecast McGill Real Time Mesoscale Cascade Domain 1 (36km) Domain 2 (12km) Domain 3 (3km) All runs completed by 0500 Eastern Standard Time

10. Production Suite SynopticMesoscale Traditional upper-level forcings and QG dynamics Visualization of processes and forcings occurring at small scales

11. Production Suite Synoptic Traditional upper-level forcings and QG dynamics dynamic tropopause potential temperature

12. Production Suite Synoptic Traditional upper-level forcings and QG dynamics isentropic potential vorticity dynamic tropopause 

13. Production Suite Synoptic Traditional upper-level forcings and QG dynamics coupling index  dt -  e(bl) dynamic tropopause  isentropic potential vorticity

14. Production Suite Synoptic Traditional upper-level forcings and QG dynamics moisture transport dynamic tropopause  isentropic potential vorticity coupling index

15. Production Suite Synoptic Traditional upper-level forcings and QG dynamics moisture flux divergence dynamic tropopause  isentropic potential vorticity coupling index moisture transport

16. Production Suite Synoptic Traditional upper-level forcings and QG dynamics Non-standard synoptic output available on 36 and 12 km domains (1 & 2) dynamic tropopause  isentropic potential vorticity coupling index moisture transport moisture flux divergence

17. Production Suite Mesoscale Visualization of processes and forcings occurring at small scales frontogenesis function and terms

18. Production Suite Mesoscale Visualization of processes and forcings occurring at small scales high-resolution convective and explicit precip- itation frontogenesis function

19. Production Suite Mesoscale Visualization of processes and forcings occurring at small scales high resolution vertical motion fields frontogenesis function high resolution precipitation

20. Production Suite Mesoscale Visualization of processes and forcings occurring at small scales cross-sectional plots of various thermodynamic variables frontogenesis function high resolution precipitation high resolution vertical motion

21. Production Suite Mesoscale Visualization of processes and forcings occurring at small scales cross-sectional plots of frontal circulations frontogenesis function high resolution precipitation high resolution vertical motion thermodynamic cross-sections

22. Production Suite Mesoscale Visualization of processes and forcings occurring at small scales Mesoscale visualization tools available on 12 and 3 km domains (2 & 3) frontogenesis function high resolution precipitation high resolution vertical motion thermodynamic cross-sections frontal circulations

23. Case Study (2 May) GOES-East Water vapour 0000UTC 2 May

24. Precipitation Structure Radar ObservationsModel Rain Rate 0900 UTC 2 May 2002 (initialized 0000 1 May) Domain 2 (12 km)

25. Precipitation Structure Radar ObservationsModel Rain Rate 1200 UTC 2 May 2002 (initialized 0000 1 May) Domain 2 (12 km)

26. Project Timeline MarchJuneSeptemberDecember 20022003 model implementation McGill-side storage structure analysis tool construction visualization design web interface construction real time modelling completed in progress planned

27. Case Study (27 Sept) GOES-East Water vapour (0000 UTC 27 Sept)

28. Precipitation Domain 1 (36km) total 24 hour rainfall ending 1200 UTC 28 Sept

29. Precipitation Observed total 24 hour rainfall ending 1200 UTC 28 Sept

30. Precipitation Domain 2 (12km) total 24 hour rainfall ending 1200 UTC 28 Sept

31. Precipitation Domain 3 (3km) total 24 hour rainfall ending 1200 UTC 28 Sept

32. Precipitation Domain 3 (3km) total 24 hour rainfall ending 1200 UTC 28 Sept

33. 500mb Height/Vorticity

34. 325K Potential Vorticity

35. Dynamic Tropopause Potential Temperature McGill 24h forecastRUC analysis 00Z 28

36. Dynamic Tropopause Windspeed / Wind Vectors McGill 24h forecastRUC analysis 00Z 28

37. Project Timeline MarchJuneSeptemberDecember 20022003 model implementation McGill-side storage structure analysis tool construction visualization design web interface construction real time modelling completed in progress planned

38. Summary Implementation of real time mesoscale NWP is under way at McGill High resolution (3 km) will enhance mesoscale flow and QPF forecasts for the St. Lawrence / NE states region

39. Data Access http://132.206.43.151:5080 Grib files available to ftp servers upon request to: rmctc@zephyr.meteo.mcgill.ca