1. Verification of USDA-MARC Heat Stress Forecasts Preliminary Results

2. Three Time Periods from 2008 July 20 – July 22 July 25 – July 27 July 31 – August 3 For this study a forecast breathing rate error of 20 breaths / minute or greater is considered excessive Verification of USDA-MARC Heat Stress Forecasts Preliminary Results Predicted Breathing RateHeat Stress Category <= 90 breaths per minuteNormal 91 – 110 breaths per minuteAlert 111-130 breaths per minuteDanger > 130 breaths per minuteEmergency

3. July 20 – July 22

4. Observed Heat Stress 07/20/08

5. Observed Heat Stress 07/21/08

6. Observed Heat Stress 07/22/08

7. 07/18/08 Day 3 Heat Stress Forecast Error (forecast for 07/20/08)

8. 07/19/08 Day 2 Heat Stress Forecast Error (forecast for 07/20/08)

9. 07/20/08 Day 1 Heat Stress Forecast Error (forecast for 07/20/08)

10. 07/19/08 Day 3 Heat Stress Forecast Error (forecast for 07/21/08)

11. 07/20/08 Day 2 Heat Stress Forecast Error (forecast for 07/21/08)

12. 07/21/08 Day 1 Heat Stress Forecast Error (forecast for 07/21/08)

13. 07/20/08 Day 3 Heat Stress Forecast Error (forecast for 07/22/08)

14. 07/21/08 Day 2 Heat Stress Forecast Error (forecast for 07/22/08)

15. 07/22/08 Day 1 Heat Stress Forecast Error (forecast for 07/22/08)

16. 07/20/08 – 07/22/08 ForecastBreathing Rate Average Mean Absolute Error Day 317.287 breaths / minute Day 214.674 breaths / minute Day 112.865 breaths / minute

17. July 25 – July 27

18. Observed Heat Stress 07/25/08

19. Observed Heat Stress 07/26/08

20. Observed Heat Stress 07/27/08

21. 07/23/08 Day 3 Heat Stress Forecast Error (forecast for 07/25/08)

22. 07/24/08 Day 2 Heat Stress Forecast Error (forecast for 07/25/08)

23. 07/25/08 Day 1 Heat Stress Forecast Error (forecast for 07/25/08)

24. 07/24/08 Day 3 Heat Stress Forecast Error (forecast for 07/26/08)

25. 07/25/08 Day 2 Heat Stress Forecast Error (forecast for 07/26/08)

26. 07/26/08 Day 1 Heat Stress Forecast Error (forecast for 07/26/08)

27. 07/25/08 Day 3 Heat Stress Forecast Error (forecast for 07/27/08)

28. 07/26/08 Day 2 Heat Stress Forecast Error (forecast for 07/27/08)

29. 07/27/08 Day 1 Heat Stress Forecast Error (forecast for 07/27/08)

30. 07/25/08 – 07/27/08 ForecastBreathing Rate Average Mean Absolute Error Day 322.154 breaths / minute Day 220.839 breaths / minute Day 117.894 breaths / minute

31. July 31 – August 3

32. Observed Heat Stress 07/31/08

33. Observed Heat Stress 08/01/08

34. Observed Heat Stress 08/02/08

35. Observed Heat Stress 08/03/08

36. 07/29/08 Day 3 Heat Stress Forecast Error (forecast for 07/31/08)

37. 07/30/08 Day 2 Heat Stress Forecast Error (forecast for 07/31/08)

38. 07/31/08 Day 1 Heat Stress Forecast Error (forecast for 07/31/08)

39. 07/30/08 Day 3 Heat Stress Forecast Error (forecast for 08/01/08)

40. 07/31/08 Day 2 Heat Stress Forecast Error (forecast for 08/01/08)

41. 08/01/08 Day 1 Heat Stress Forecast Error (forecast for 08/01/08)

42. 07/31/08 Day 3 Heat Stress Forecast Error (forecast for 08/02/08)

43. 08/01/08 Day 2 Heat Stress Forecast Error (forecast for 08/02/08)

44. 08/02/08 Day 1 Heat Stress Forecast Error (forecast for 08/02/08)

45. 08/01/08 Day 3 Heat Stress Forecast Error (forecast for 08/03/08)

46. 08/02/09 Day 2 Heat Stress Forecast Error (forecast for 08/03/08)

47. 08/03/08 Day 1 Heat Stress Forecast Error (forecast for 08/03/08)

48. 07/31/08 – 08/03/08 ForecastBreathing Rate Average Mean Absolute Error Day 318.596 breaths / minute Day 215.475 breaths / minute Day 112.902 breaths / minute

49. Breathing rate equation verified fairly well during these three time periods Day 2 and day 3 forecasts from 07/25 – 07/27 produced greatest forecast breathing rate error Conclusions…

50. Forecast temperature most responsible for error in forecast breathing rate Breathing Rate =(2.83 X Temperature) + (0.58 X Humidity) – (0.76 X Wind Speed) + (0.429 X (100 – Cloud Cover)) – 196.4 Forecast relative humidity off by 8% - 12% We (NWS forecasters) could benefit heat stress forecasts greatly through improved relative humidity forecasts Conclusions…

51. Roger Eigenberg (USDA-MARC) Tami Brown-Brandl (USDA-MARC) Scott Opbroek (USDA-MARC) Randy Bradley (USDA-MARC) Rick Ewald (NWS) Aaron Johnson (NWS) Thank You

52. Questions http://www.ars.usda.gov