VERIFICATION TO W.M.O. STANDARDS ---------------------------------------- N.C.E.P./U.S.A. SEPTEMBER 2009 ------------------------------------------------ NORTH AMERICAN MODEL (NAM) ----------------------------------- # ** NCEP/USA NAM MODEL ** TABLE 4.1 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA GEOPOTENTIAL HEIGHT SEPTEMBER2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -3.10 -0.27 8.12 8.09 24 -1.03 0.38 8.78 8.39 36 -1.44 -0.17 9.86 10.57 48 -1.38 0.31 11.88 11.92 60 -2.43 -1.16 13.99 14.26 72 -3.40 -1.70 16.42 17.02 84 -4.12 -2.48 19.37 20.24 TABLE 4.2 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA GEOPOTENTIAL HEIGHT SEPTEMBER2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -3.47 -1.72 9.39 9.56 24 -1.56 -2.24 10.54 10.97 36 -2.66 -2.62 13.03 13.49 48 -1.63 -2.49 15.30 16.14 60 -3.04 -3.24 18.95 19.32 72 -3.45 -3.53 21.73 23.77 84 -4.83 -4.09 27.20 27.26 TABLE 4.3 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA GEOPOTENTIAL HEIGHT SEPTEMBER2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 6.40 7.41 13.64 14.78 24 10.63 7.95 19.04 17.39 36 11.13 10.72 22.55 22.75 48 14.76 11.39 28.92 26.49 60 13.18 12.79 32.01 32.29 72 15.14 12.35 38.31 38.06 84 13.07 13.50 44.55 44.69 # ** NCEP/USA NAM MODEL ** TABLE 4.4 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA TEMPERATURE SEPTEMBER2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.20 -0.07 1.16 1.14 24 0.16 -0.04 1.26 1.28 36 0.19 -0.06 1.42 1.39 48 0.19 -0.06 1.54 1.56 60 0.19 -0.05 1.72 1.72 72 0.19 -0.09 1.85 1.83 84 0.15 -0.04 2.07 2.09 TABLE 4.5 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA TEMPERATURE SEPTEMBER2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.27 0.31 0.85 0.90 24 0.29 0.22 0.96 0.96 36 0.26 0.33 1.03 1.15 48 0.39 0.29 1.25 1.23 60 0.35 0.39 1.34 1.45 72 0.49 0.38 1.53 1.53 84 0.43 0.48 1.68 1.76 TABLE 4.6 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA TEMPERATURE SEPTEMBER2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 1.10 1.07 1.42 1.40 24 1.23 1.16 1.63 1.57 36 1.35 1.31 1.79 1.80 48 1.45 1.34 1.99 1.93 60 1.48 1.47 2.10 2.10 72 1.52 1.41 2.24 2.17 84 1.50 1.49 2.30 2.34 # ** NCEP/USA NAM MODEL ** TABLE 4.7 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA WIND SEPTEMBER2009 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.41 -0.52 3.34 3.53 24 -0.30 -0.51 3.70 3.86 36 -0.32 -0.47 3.96 4.26 48 -0.38 -0.46 4.51 4.69 60 -0.42 -0.51 4.83 5.15 72 -0.32 -0.53 5.25 5.46 84 -0.43 -0.41 5.58 5.92 TABLE 4.8 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA WIND SEPTEMBER2009 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.42 -0.48 3.77 3.75 24 -0.36 -0.37 4.15 4.24 36 -0.34 -0.44 4.78 4.77 48 -0.33 -0.42 5.19 5.39 60 -0.52 -0.55 5.87 5.83 72 -0.47 -0.60 6.38 6.68 84 -0.59 -0.64 7.21 7.35 TABLE 4.9 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA WIND SEPTEMBER2009 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.24 0.03 5.06 5.24 24 -0.29 -0.38 6.31 6.15 36 -0.42 -0.17 7.37 7.42 48 -0.37 -0.59 8.51 8.26 60 -0.69 -0.57 9.78 9.36 72 -0.79 -0.83 10.91 11.17 84 -1.12 -0.79 12.42 12.48