VERIFICATION TO W.M.O. STANDARDS ---------------------------------------- N.C.E.P./U.S.A. AUGUST 2011 ------------------------------------------------ NORTH AMERICAN MODEL (NAM) ----------------------------------- # ** NCEP/USA NAM MODEL ** TABLE 4.1 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA GEOPOTENTIAL HEIGHT AUGUST 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -3.35 -0.52 7.73 7.41 24 -1.13 -0.95 8.20 7.82 36 -4.32 -2.30 10.04 9.76 48 -4.16 -4.34 11.81 11.67 60 -6.15 -4.52 14.03 13.90 72 -6.49 -5.33 16.16 15.42 84 -6.17 -4.95 18.30 18.25 TABLE 4.2 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA GEOPOTENTIAL HEIGHT AUGUST 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -5.44 -2.95 10.07 9.25 24 -3.97 -3.80 10.08 10.43 36 -6.84 -5.47 12.82 12.91 48 -6.58 -6.81 14.68 14.81 60 -8.56 -7.21 17.40 18.06 72 -8.61 -7.82 20.66 20.04 84 -8.26 -7.72 22.82 23.33 TABLE 4.3 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA GEOPOTENTIAL HEIGHT AUGUST 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 1.18 2.57 11.05 11.72 24 2.78 2.10 13.96 13.94 36 1.64 1.62 17.23 17.83 48 2.29 0.84 20.95 21.36 60 0.99 1.24 25.49 26.98 72 1.01 1.70 31.11 30.85 84 2.89 2.74 37.38 36.07 # ** NCEP/USA NAM MODEL ** TABLE 4.4 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA TEMPERATURE AUGUST 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.13 -0.08 1.15 1.19 24 0.07 0.02 1.24 1.31 36 0.10 -0.05 1.37 1.44 48 0.08 0.00 1.46 1.61 60 0.07 0.01 1.63 1.67 72 0.01 -0.03 1.69 1.81 84 0.01 -0.06 1.88 1.96 TABLE 4.5 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA TEMPERATURE AUGUST 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.16 0.14 0.83 0.86 24 0.13 0.06 0.92 0.92 36 0.13 0.08 1.00 1.02 48 0.15 0.10 1.13 1.14 60 0.15 0.09 1.22 1.29 72 0.17 0.15 1.38 1.36 84 0.18 0.18 1.50 1.54 TABLE 4.6 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA TEMPERATURE AUGUST 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.85 0.76 1.22 1.16 24 0.88 0.86 1.36 1.36 36 0.99 0.91 1.54 1.50 48 1.01 0.92 1.69 1.64 60 1.02 0.98 1.86 1.81 72 1.09 1.00 1.98 1.95 84 1.11 1.05 2.13 2.04 # ** NCEP/USA NAM MODEL ** TABLE 4.7 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA WIND AUGUST 2011 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.52 -0.63 3.57 3.74 24 -0.51 -0.49 3.82 4.02 36 -0.44 -0.63 4.15 4.38 48 -0.56 -0.42 4.48 4.90 60 -0.42 -0.51 4.87 5.10 72 -0.49 -0.42 5.37 5.60 84 -0.33 -0.45 5.55 5.91 TABLE 4.8 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA WIND AUGUST 2011 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.32 -0.22 3.88 3.88 24 -0.42 -0.13 4.23 4.25 36 -0.27 -0.19 4.75 4.68 48 -0.41 -0.04 4.99 5.17 60 -0.22 -0.14 5.57 5.69 72 -0.36 0.08 6.23 6.13 84 -0.23 -0.14 6.62 6.89 TABLE 4.9 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA WIND AUGUST 2011 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.29 -0.54 4.93 5.26 24 -0.44 -0.83 6.25 6.16 36 -0.41 -0.64 6.99 7.21 48 -0.61 -1.07 8.10 8.25 60 -0.86 -1.24 9.15 9.48 72 -0.89 -1.39 10.43 10.52 84 -1.19 -1.70 11.50 11.19