1. Severe weather events in Southern Brazil and their similarity with events in the United States Bruno Ribeiro, Lance Bosart National Institute for Space Research - INPE, Brazil SUNY - University at Albany, NY 16th NROW - November 2015

2. Purpose:

3. Compare severe weather events in Southern Brazil to that in the U.S. and show some forecast issues.

4. Purpose: Compare severe weather events in Southern Brazil to that in the U.S. and show some forecast issues. Motivation: - Little research on severe weather in South America;

5. Purpose: Compare severe weather events in Southern Brazil to that in the U.S. and show some forecast issues. Motivation: - Little research on severe weather in South America; - Most conceptual models of severe weather for the U.S. are applicable in Southern Brazil;

6. Purpose: Compare severe weather events in Southern Brazil to that in the U.S. and show some forecast issues. Motivation: - Little research on severe weather in South America; - Most conceptual models of severe weather for the U.S. are applicable in Southern Brazil; - Look for when these models may NOT be applicable in Southern Brazil.

7. Introduction 1) Similarities between North and South America;

8. Introduction 1) Similarities between North and South America; 2) Two cases: - A Squall Line in Sao Paulo state on 08 September 2015;

9. Introduction 1) Similarities between North and South America; 2) Two cases: - A Squall Line in Sao Paulo state on 08 September 2015; - A EF2-EF3 tornado case in Santa Catarina State on 20 April 2015.

10. South America Topography

12. ’Classic’ severe weather environment

14. Elevated Mixed Layers and Supercells

17. Bow-echoes

18. Squall Line Case

19. Affected most of the Sao Paulo state, including Sao Paulo metropolitan region:

20. Squall Line Case Affected most of the Sao Paulo state, including Sao Paulo metropolitan region: - Hundreds of downed trees and flooded streets;

21. Squall Line Case Affected most of the Sao Paulo state, including Sao Paulo metropolitan region: - Hundreds of downed trees and flooded streets; - Several 5 cm ( 2”) hail reports;

22. Squall Line Case Affected most of the Sao Paulo state, including Sao Paulo metropolitan region: - Hundreds of downed trees and flooded streets; - Several 5 cm ( 2”) hail reports; - Wind gusts peaked 120 km/h (65 kt) in the entrance of Paraiba Valley.

23. Squall Line Case - Synoptic Environment

26. Weak quasi-geostrophic forcing

27. Squall Line Case - Synoptic Environment

29. Divergent upper-level flow at jet-streak equatorial entrance

30. Squall Line Case - Synoptic Environment

34. Low-level cyclonic vorticity associated with the front

35. Squall Line Case - soundings

37. Squall Line Case - satellite imagery

43. Squall Line Case - radar imagery

56. Tornado Case

57. Estimated EF2-EF3 tornado affected the city of Xanxere on 20 April 2015:

58. Tornado Case Estimated EF2-EF3 tornado affected the city of Xanxere on 20 April 2015: - 2 people dead and hundreds injured;

59. Tornado Case Estimated EF2-EF3 tornado affected the city of Xanxere on 20 April 2015: - 2 people dead and hundreds injured; - Severe damage to about 50% of the city.

60. Tornado Case

64. Tornado Case - Synoptic Environment

67. Weak quasi-geostrophic forcing:

68. Tornado Case - Synoptic Environment

74. Tornado Case - Forecast issues

78. Conclusions

79. Large-scale severe weather environments are similar:

80. Conclusions Large-scale severe weather environments are similar: 1- Strong low-level jet bringing warm and moist air from the tropics;

81. Conclusions Large-scale severe weather environments are similar: 1- Strong low-level jet bringing warm and moist air from the tropics; 2- Severe weather along a low-level baroclinic region.

82. Conclusions Large-scale severe weather environments are similar: 1- Strong low-level jet bringing warm and moist air from the tropics; 2- Severe weather along a low-level baroclinic region. 3- Upper-level forcing by the Subtropical/Polar Jet.

83. Conclusions Large-scale severe weather environments are similar: 1- Strong low-level jet bringing warm and moist air from the tropics; 2- Severe weather along a low-level baroclinic region. 3- Upper-level forcing by the Subtropical/Polar Jet. 4- South America also have ‘cold season’ and ‘warm season’ patterns;

84. Conclusions - Issues and future research

85. - Role of drylines (?) and local topography in triggering severe convection;

86. Conclusions - Issues and future research - Role of drylines (?) and local topography in triggering severe convection; - Elevated mixed layers

87. Conclusions - Issues and future research - Role of drylines (?) and local topography in triggering severe convection; - Elevated mixed layers Observational framework must be improved:

88. Conclusions - Issues and future research - Role of drylines (?) and local topography in triggering severe convection; - Elevated mixed layers Observational framework must be improved: - Radars, soundings and surface observations;

89. Conclusions - Issues and future research - Role of drylines (?) and local topography in triggering severe convection; - Elevated mixed layers Observational framework must be improved: - Radars, soundings and surface observations; - Severe weather reports network.

90. Thank you