1. A M ULTISCALE A NALYSIS OF A H EAVY R AINFALL E VENT OVER L AKE M ICHIGAN Jason M. Cordeira D EPARTMENT OF A TMOSPHERIC AND E NVIRONMENTAL S CIENCES U NIVERSITY AT A LBANY, S TATE U NIVERSITY OF N EW Y ORK NROW XIII Wednesday 2 November 2011 Nicholas D. Metz DEPARTMENT OF GEOSCIENCE HOBART AND WILLIAM SMITH COLLEGES

2. O BJECTIVES To investigate far-upstream precursors to heavy rainfall events (HREs) in the Great Lakes region To investigate the possible role of Lake Michigan (LM) on difficult to predict HREs in the Great Lakes region

3. O UTLINE Motivation Radar overview Far-upstream precursors Synoptic-scale and mesoscale analysis WRF simulation

4. O UTLINE Motivation Radar Overview Far-upstream precursors Synoptic-scale and mesoscale analysis WRF simulation

5. MOTIVATION – PRECIPITATION TOTALS 48-h precipitation totals >150 mm (>6 in) over LM 48-h precipitation totals ~100 mm (~4 in) over northern Indiana image source: http://nmq.ou.edu 48-h precipitation totals ending 0000 UTC 2 July 2011

6. Valparaiso, IN – 91.7 mm precipitation on 1 July 2011 – 100.8 mm precipitation in 24-h period ending 0000 UTC 2 July 2011 – 30-d precipitation ending 0000 UTC 1 July 2011: 87.4 mm – 30-d precipitation ending 0000 UTC 2 July 2011: 188.2 mm – 1-in-5-yr event (http://hdsc.nws.noaa.gov/hdsc/pfds/) image source: http://nmq.ou.edu 24-h precipitation totals ending 0000 UTC 1 July 2011 24-h precipitation totals ending 0000 UTC 2 July 2011 MOTIVATION – PRECIPITATION TOTALS

7. Severe weather confined to Chicago region overnight 30 June to 1 July 2011 Subsequent severe weather event over MN, WI, IA, SD late on 1 July 2011 image source: http://www.spc.noaa.gov 30 June 2011 Storm Reports 1 July 2011 Storm Reports MOTIVATION – SEVERE WEATHER image courtesy ABC-7 Chicago

8. MOTIVATION – NAM (WRF-NMM) QPF Area-averaged accumulated precipitation (28 June forecasts) Area-averaged domain: NCEP 4-km stage IV NAM (WRF-NMM)

9. MOTIVATION – NAM (WRF-NMM) QPF Area-averaged accumulated precipitation (29 June forecasts) NCEP 4-km stage IV NAM (WRF-NMM) Area-averaged domain:

10. MOTIVATION – NAM (WRF-NMM) QPF Area-averaged accumulated precipitation (29 June forecasts) NCEP 4-km stage IV NAM (WRF-NMM) Area-averaged domain: Forecasts largely miss 1800 UTC 30 June to 0600 UTC 1 July precipitation

11. O UTLINE Motivation Radar overview – 1800 UTC 30 June – 0600 UTC 1 July 2011 Far-upstream precursors Synoptic-scale and mesoscale analysis WRF simulation

12. RADAR OVERVIEW – 30 JUNE–1 JULY 2011 1200 UTC 30 June image source: http://locust.mmm.ucar.edu/

13. RADAR OVERVIEW – 30 JUNE–1 JULY 2011 1300 UTC 30 June

14. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 1400 UTC 30 June

15. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 1500 UTC 30 June

16. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 1600 UTC 30 June

17. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 1700 UTC 30 June

18. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 1800 UTC 30 June

19. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 1900 UTC 30 June

20. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 2000 UTC 30 June

21. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 2100 UTC 30 June

22. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 2200 UTC 30 June

23. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 2300 UTC 30 June

24. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 0000 UTC 1 July

25. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 0100 UTC 1 July

26. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 0200 UTC 1 July

27. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 0300 UTC 1 July

28. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 0400 UTC 1 July

29. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 0500 UTC 1 July

30. image source: http://locust.mmm.ucar.edu/ RADAR OVERVIEW – 30 JUNE–1 JULY 2011 0600 UTC 1 July

31. RADAR SUMMARY – 30 JUNE–1 JULY 2011 System 1 × × × × × System 2System 3System 4 17 18 19 20 21 22 23 00 01 02 01 02 03 00 01 02 03 04 03 04 05 Convection features four quasi-linear systems: System 1: 1700 UTC 30 June to 2100 UTC 30 June 2011 System 2: 2200 UTC 30 June to 0300 UTC 1 July 2011 – evolves into two right-moving supercells (×) System 3: 0000 UTC 1 July to 0400 UTC 1 July 2011 System 4: 0300 UTC 1 July to 0500 UTC 1 July 2011

32. O UTLINE Motivation Radar overview Far-upstream precursors Synoptic-scale and mesoscale analysis WRF simulation

33. F AR - UPSTREAM PRECURSORS The evolution of the large-scale flow over North America is often influenced by variability in the large-scale flow over North Pacific Variability in the large-scale flow over North Pacific is often influenced by tropical cyclones

34. F AR - UPSTREAM PRECURSORS Tropical Storm Haima (18–25 June 2011)Tropical Storm Meari (22–27 June 2011) image source: http://agora.ex.nii.ac.jp/digital-typhoon/index.html.en The evolution of the large-scale flow over North America is often influenced by variability in the large-scale flow over North Pacific Variability in the large-scale flow over North Pacific is often influenced by tropical cyclones What is the influence of tropical storms Haima and Meari on the evolution of the large-scale flow over North America? Meari Haima

35. 0000 UTC 22 June 2011 Precipitable water (mm; shade), 850-hPa rel. vor. (10 −4 s −1 ; white), DT wind speed (m s −1 ; black), and 700-hPa wind (knots; barbs) F AR - UPSTREAM PRECURSORS H M source: 0.5° NCEP–GFS

36. 0000 UTC 24 June 2011 Precipitable water (mm; shade), 850-hPa rel. vor. (10 −4 s −1 ; white), DT wind speed (m s −1 ; black), and 700-hPa wind (knots; barbs) F AR - UPSTREAM PRECURSORS H M source: 0.5° NCEP–GFS

37. 0000 UTC 24 June 2011 Precipitable water (mm; shade), 850-hPa rel. vor. (10 −4 s −1 ; white), DT wind speed (m s −1 ; black), 300–200-hPa PV (PVU; thin black), and 250-hPa irrotational wind (m s −1 ; vectors) F AR - UPSTREAM PRECURSORS H M source: 0.5° NCEP–GFS 10 m s −1

38. 0000 UTC 26 June 2011 Precipitable water (mm; shade), 850-hPa rel. vor. (10 −4 s −1 ; white), DT wind speed (m s −1 ; black), and 700-hPa wind (knots; barbs) F AR - UPSTREAM PRECURSORS M source: 0.5° NCEP–GFS

39. 0000 UTC 26 June 2011 DT potential temperature (K; shade), DT wind speed (m s −1 ; black), DT wind (knots; barbs), and 850-hPa rel. vor. (10 −4 s −1 ; white) F AR - UPSTREAM PRECURSORS M source: 0.5° NCEP–GFS

40. 0000 UTC 26 June 2011 DT potential temperature (K; shade), DT wind speed (m s −1 ; black), DT wind (knots; barbs), and 850-hPa rel. vor. (10 −4 s −1 ; white) F AR - UPSTREAM PRECURSORS Shifted domain source: 0.5° NCEP–GFS

41. 0000 UTC 28 June 2011 DT potential temperature (K; shade), DT wind speed (m s −1 ; black), DT wind (knots; barbs), and 850-hPa rel. vor. (10 −4 s −1 ; white) F AR - UPSTREAM PRECURSORS source: 0.5° NCEP–GFS

42. 0000 UTC 30 June 2011 DT potential temperature (K; shade), DT wind speed (m s −1 ; black), DT wind (knots; barbs), and 850-hPa rel. vor. (10 −4 s −1 ; white) F AR - UPSTREAM PRECURSORS source: 0.5° NCEP–GFS

43. 0000 UTC 30 June 2011 DT potential temperature (K; shade), DT wind speed (m s −1 ; black), DT wind (knots; barbs), and 850-hPa rel. vor. (10 −4 s −1 ; white) F AR - UPSTREAM PRECURSORS source: 0.5° NCEP–GFS

44. 0000 UTC 30 June 2011 700–500-hPa lapse rate (K km −1 ; shade), 700–500-hPa wind (knots; barbs), and 200-hPa geo. height (dam; black) F AR - UPSTREAM PRECURSORS DTθ source: 0.5° NCEP–GFS

45. F AR - UPSTREAM P RECURSORS 40°–50°N 20 June–10 July 2011 700–500-hPa lapse rate (K km −1 ; shade), 250-hPa meridional wind anomaly (every 10 m s −1 ; red/blue contours), and 250-hPa zonal wind speed (every 5 m s −1 starting at 30; dash) source: 0.5° NCEP–GFS

46. 20 June–10 July 2011 700–500-hPa lapse rate (K km −1 ; shade), 250-hPa meridional wind anomaly (every 10 m s −1 ; red/blue contours), and 250-hPa zonal wind speed (every 5 m s −1 starting at 30; dash) F AR - UPSTREAM P RECURSORS 40°–50°N “PRE”

47. O UTLINE Motivation Radar overview Far-upstream precursors Synoptic-scale and mesoscale analysis WRF simulation

48. SYNOPTIC-SCALE AND MESOSCALE ANALYSIS 1800 UTC 30 June 2011 250-hPa geo. height (dam; solid) and wind speed (m s −1 ; shade), and 850-hPa wind (knots; barbs) source: RUC 20-km Low-level jet

49. S YNOPTIC - SCALE AND MESOSCALE ANALYSIS 1800 UTC 30 June 2011 1000–500-hPa thick (dam; dash), SLP (hPa; solid), 925-hPa mixing ratio (g kg −1 ; shade), and 10- m wind (knots; barbs) source: RUC 20-km

50. S YNOPTIC - SCALE AND MESOSCALE ANALYSIS 1800 UTC 30 June 2011 Most-unstable CAPE (J kg −1 ; shade) and 0-to-6-km shear (knots; barbs) source: RUC 20-km

51. S YNOPTIC - SCALE AND MESOSCALE ANALYSIS 1800 UTC 30 June 2011 Manual surface analysis: temperature (°C; red), mixing ratio (g kg −1 ; green), and SLP (hPa; black) Base reflectivity (dBZ; shaded) warm front

52. S YNOPTIC - SCALE AND MESOSCALE ANALYSIS 1800 UTC 30 June 2011 Manual surface analysis: temperature (°C; red), mixing ratio (g kg −1 ; green), and SLP (hPa; black) Base reflectivity (dBZ; shaded) WE

53. S YNOPTIC - SCALE AND MESOSCALE ANALYSIS 1800 UTC 30 June 2011 Cross sectional potential temperature (K; gray), mixing ratio (g kg −1 ; shaded), wind (knots), and horizontal temperature advection (K d −1 ; dashed every 10 K d −1 ) WE LMWIMNMI 69121518 g kg −1 source: RUC 20-km Pressure (hPa)

54. S YNOPTIC - SCALE AND MESOSCALE ANALYSIS 0000 UTC 1 July 2011 1000–500-hPa thick (dam; dash), SLP (hPa; solid), 925-hPa mixing ratio (g kg −1 ; shade), and 10- m wind (knots; barbs) source: RUC 20-km

55. S YNOPTIC - SCALE AND MESOSCALE ANALYSIS 0000 UTC 1 July 2011 Most-unstable CAPE (J kg −1 ; shade) and 0-to-6-km shear (knots; barbs) source: RUC 20-km

56. S YNOPTIC - SCALE AND MESOSCALE ANALYSIS 0000 UTC 1 July 2011 University of Wyoming Sounding

57. S YNOPTIC - SCALE AND MESOSCALE ANALYSIS 0000 UTC 1 July 2011 Manual surface analysis: temperature (°C; red), mixing ratio (g kg −1 ; green), and SLP (hPa; black) Base reflectivity (dBZ; shaded) warm front

58. S YNOPTIC - SCALE AND MESOSCALE ANALYSIS 0000 UTC 1 July 2011 Manual surface analysis: temperature (°C; red), mixing ratio (g kg −1 ; green), and SLP (hPa; black) Base reflectivity (dBZ; shaded) WE

59. S YNOPTIC - SCALE AND MESOSCALE ANALYSIS 0000 UTC 1 July 2011 Cross sectional potential temperature (K; gray), mixing ratio (g kg −1 ; shaded), wind (knots), and horizontal temperature advection (K d −1 ; dashed every 10 K d −1 ) WE LMWIMNMI 69121518 g kg −1 source: RUC 20-km Pressure (hPa)

60. S YNOPTIC - SCALE AND MESOSCALE ANALYSIS Pressure (hPa) Temperature (°C) 1800 UTC 30 June 20110000 UTC 1 July 2011 source: RUC 20-km RUC soundings

61. S YNOPTIC - SCALE AND MESOSCALE ANALYSIS Pressure (hPa) 1800 UTC 30 June 2011 0000 UTC 1 July 2011 MAUL? Moist-Absolutely Unstable Layer (MAUL) criterion satisfied in RUC sounding at 0000 UTC 1 July 2011 (dewpoint depression <1°C and Δθ e /Δz<0) MAULs are maintained in regions of strong mesoscale dynamic ascent in the presence of weak convective instability (Bryan and Fritsch 2000)

62. O UTLINE Motivation Radar Overview Far-upstream precursors Synoptic-scale and mesoscale analysis WRF simulation

63. WRF SIMULATION 4-km WRF-ARW simulation initialized at 1200 UTC 30 June 2011 4-km WRF-ARW simulation for 1200 UTC 30 Jun–1200 UTC 1 Jul 2011 Initialized with and without LM (LM and No-LM, respectively) Physics: WSM-6; Cumulus: explicit; Surface: thermal diffusion Initialized with LM Initialized without LM LM grid points replaced with sub-surface and surface characteristics of Wisconsin grid point LM (control)No-LM

64. WRF SIMULATION AND COMPARISON 12-h forecast verifying 0000 UTC 1 July 2011 Simulated reflectivity (dBZ; shaded), 2-m pot. temp. (K; contours); and 10-m wind (knots; barbs) LM (control)No-LM Observed: NAM 12-h simulated reflectivity:HRRR 12-h simulated reflectivity:

65. 30 June–1 July 2011 convective event associated with 24-h precipitation totals >100 mm over western Great Lakes region Rossby wave train amplification and dispersion associated with western North Pacific tropical cyclones Meari and Haima produced favorable environmental conditions for convection and heavy precipitation over the western Great Lakes region Elevated convection developed along a north-south oriented surface baroclinic zone (warm front) at the nose the low-level jet and in the presence of strong WAA, deep-tropospheric moisture, enhanced midtropospheric static instability, and moist absolute instability S UMMARY 1

66. Convection developed along the shorelines of LM where the LM “cold dome” and strong horizontal temperature gradients may have favored enhanced local ascent and organized convection, respectively Influence of LM on convective development was likely secondary to the synoptic and mesoscale environment WRF initialized with and without LM at 1200 UTC 30 June 2011 failed to produce the elevated convective event between 1800 UTC and 0600 UTC 1 July 2011 S UMMARY 2

67. HRE S Annual frequency of warm season 24-h precipitation events >25 mm Data source: Unified Precipitation Dataset (UPD) May–October 1984–2003