VERIFICATION TO W.M.O. STANDARDS ---------------------------------------- N.C.E.P./U.S.A. JULY 2011 ------------------------------------------------ NORTH AMERICAN MODEL (NAM) ----------------------------------- # ** NCEP/USA NAM MODEL ** TABLE 4.1 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA GEOPOTENTIAL HEIGHT JULY 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -2.28 0.79 7.51 7.99 24 -0.11 -0.26 8.41 8.07 36 -3.12 -1.05 9.49 9.69 48 -3.40 -3.57 11.76 11.49 60 -5.73 -4.67 14.27 13.92 72 -5.48 -5.76 16.22 16.58 84 -6.57 -4.88 18.53 18.50 TABLE 4.2 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA GEOPOTENTIAL HEIGHT JULY 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -4.58 -1.70 9.53 8.83 24 -2.55 -3.23 9.47 10.21 36 -5.87 -3.82 12.44 12.09 48 -5.72 -6.38 14.63 14.67 60 -7.87 -7.06 17.77 17.73 72 -7.77 -8.26 20.76 20.17 84 -8.97 -7.05 23.88 23.45 TABLE 4.3 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA GEOPOTENTIAL HEIGHT JULY 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 1.29 4.38 11.19 11.61 24 4.55 3.46 14.01 13.54 36 2.31 4.00 16.45 16.96 48 3.11 2.01 21.43 20.05 60 0.86 2.07 25.25 25.96 72 2.06 -0.42 31.18 29.45 84 -0.01 1.01 35.84 35.54 # ** NCEP/USA NAM MODEL ** TABLE 4.4 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA TEMPERATURE JULY 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.13 -0.09 1.16 1.22 24 0.07 -0.06 1.26 1.30 36 0.04 -0.12 1.39 1.40 48 0.06 -0.13 1.54 1.51 60 0.03 -0.11 1.68 1.70 72 0.05 -0.13 1.88 1.85 84 0.02 -0.08 2.01 2.04 TABLE 4.5 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA TEMPERATURE JULY 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.13 0.17 0.83 0.86 24 0.17 0.12 0.92 0.93 36 0.13 0.21 1.02 1.02 48 0.18 0.18 1.17 1.13 60 0.15 0.22 1.24 1.27 72 0.18 0.15 1.36 1.33 84 0.18 0.19 1.48 1.44 TABLE 4.6 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA TEMPERATURE JULY 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.78 0.75 1.17 1.15 24 0.81 0.85 1.35 1.35 36 0.91 0.86 1.56 1.46 48 0.97 0.96 1.70 1.67 60 0.97 1.01 1.89 1.84 72 1.03 0.97 2.07 1.96 84 1.01 1.01 2.15 2.08 # ** NCEP/USA NAM MODEL ** TABLE 4.7 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA WIND JULY 2011 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.37 -0.61 3.52 3.79 24 -0.33 -0.60 3.76 4.01 36 -0.27 -0.62 4.02 4.44 48 -0.32 -0.55 4.37 4.76 60 -0.31 -0.50 4.56 5.22 72 -0.32 -0.38 5.06 5.55 84 -0.23 -0.48 5.43 6.06 TABLE 4.8 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA WIND JULY 2011 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.26 -0.09 3.91 3.85 24 -0.44 -0.06 4.11 4.34 36 -0.41 -0.06 4.68 4.73 48 -0.27 -0.04 5.15 5.16 60 -0.32 -0.05 5.45 5.65 72 -0.33 0.02 6.08 6.13 84 -0.33 0.12 6.53 6.74 TABLE 4.9 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA WIND JULY 2011 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.39 -0.45 5.07 5.01 24 -0.62 -0.59 6.10 5.71 36 -0.41 -0.78 6.91 6.81 48 -0.63 -0.82 7.79 7.69 60 -0.89 -0.86 8.75 8.99 72 -0.92 -1.18 9.70 9.66 84 -1.25 -1.20 10.48 11.13