VERIFICATION TO W.M.O. STANDARDS ---------------------------------------- N.C.E.P./U.S.A. APRIL 2011 ------------------------------------------------ NORTH AMERICAN MODEL (NAM) ----------------------------------- # ** NCEP/USA NAM MODEL ** TABLE 4.1 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA GEOPOTENTIAL HEIGHT APRIL 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.66 -0.45 8.75 8.59 24 -0.53 -0.71 10.04 10.25 36 -1.92 -1.02 12.13 12.62 48 -2.46 -2.63 15.17 15.69 60 -4.08 -3.80 18.70 19.60 72 -3.72 -4.73 23.50 23.66 84 -3.75 -3.05 27.62 29.42 TABLE 4.2 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA GEOPOTENTIAL HEIGHT APRIL 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -4.35 -2.81 10.40 10.28 24 -4.26 -4.05 12.57 13.05 36 -5.94 -4.42 15.94 15.96 48 -6.66 -5.69 20.01 20.29 60 -8.49 -7.72 25.20 26.56 72 -9.75 -9.12 32.00 30.90 84 -9.30 -8.12 37.56 39.68 TABLE 4.3 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA GEOPOTENTIAL HEIGHT APRIL 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 2.73 3.61 12.71 12.81 24 6.78 6.18 17.85 18.26 36 7.80 8.92 22.66 23.07 48 9.78 9.23 28.15 28.05 60 8.81 8.96 33.67 35.55 72 7.19 8.52 41.90 41.54 84 8.78 8.32 49.92 51.58 # ** NCEP/USA NAM MODEL ** TABLE 4.4 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA TEMPERATURE APRIL 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.30 -0.17 1.40 1.45 24 -0.39 -0.40 1.56 1.67 36 -0.55 -0.43 1.81 1.80 48 -0.55 -0.57 1.99 2.05 60 -0.70 -0.59 2.25 2.38 72 -0.68 -0.77 2.60 2.61 84 -0.83 -0.80 2.96 3.00 TABLE 4.5 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA TEMPERATURE APRIL 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.14 0.17 0.89 0.91 24 0.22 0.28 1.05 1.13 36 0.31 0.34 1.24 1.26 48 0.38 0.40 1.48 1.53 60 0.42 0.42 1.72 1.81 72 0.37 0.46 2.05 2.00 84 0.43 0.39 2.21 2.41 TABLE 4.6 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA TEMPERATURE APRIL 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.83 0.68 1.30 1.26 24 0.94 0.84 1.56 1.51 36 1.04 1.11 1.75 1.81 48 1.24 1.10 2.06 1.98 60 1.22 1.27 2.23 2.32 72 1.31 1.22 2.49 2.45 84 1.28 1.20 2.62 2.80 # ** NCEP/USA NAM MODEL ** TABLE 4.7 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA WIND APRIL 2011 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.24 -0.49 4.25 4.15 24 -0.15 -0.13 4.55 4.72 36 -0.06 -0.17 4.89 5.24 48 -0.16 -0.20 5.42 5.60 60 0.02 -0.18 6.01 6.50 72 -0.22 0.05 6.75 6.91 84 -0.21 -0.16 7.24 8.16 TABLE 4.8 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA WIND APRIL 2011 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.33 -0.57 4.43 4.53 24 -0.26 -0.38 4.98 5.09 36 -0.32 -0.37 5.72 5.79 48 -0.11 -0.43 6.42 6.38 60 -0.35 -0.36 7.20 7.54 72 -0.40 -0.56 8.31 8.15 84 -0.66 -0.64 9.10 9.50 TABLE 4.9 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA WIND APRIL 2011 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.25 -0.30 5.07 5.27 24 -0.37 -0.59 6.20 6.56 36 -0.64 -0.58 7.32 7.41 48 -0.51 -0.89 8.31 8.55 60 -0.98 -0.56 9.60 10.15 72 -1.02 -0.87 10.97 11.12 84 -1.35 -0.70 12.08 12.74