VERIFICATION TO W.M.O. STANDARDS ---------------------------------------- N.C.E.P./U.S.A. MARCH 2011 ------------------------------------------------ NORTH AMERICAN MODEL (NAM) ----------------------------------- # ** NCEP/USA NAM MODEL ** TABLE 4.1 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA GEOPOTENTIAL HEIGHT MARCH 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -1.85 -0.31 8.08 8.34 24 -2.04 -1.58 9.40 9.78 36 -2.99 -1.64 11.84 12.40 48 -3.91 -2.58 15.15 15.59 60 -4.49 -4.21 19.36 18.65 72 -5.89 -3.54 22.89 23.33 84 -4.14 -3.07 26.00 27.24 TABLE 4.2 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA GEOPOTENTIAL HEIGHT MARCH 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -4.89 -3.03 10.36 9.72 24 -5.34 -5.06 12.52 12.93 36 -6.48 -5.23 16.55 16.13 48 -6.98 -5.92 20.86 21.08 60 -7.54 -7.63 26.33 25.52 72 -9.43 -8.04 31.56 30.10 84 -6.88 -8.95 35.14 36.80 TABLE 4.3 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA GEOPOTENTIAL HEIGHT MARCH 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 1.36 3.19 12.59 11.88 24 4.49 4.19 16.69 16.58 36 5.74 6.66 22.35 21.82 48 6.40 7.46 28.13 28.67 60 6.95 5.91 35.04 33.82 72 4.64 6.18 41.53 43.59 84 8.20 5.18 50.42 51.07 # ** NCEP/USA NAM MODEL ** TABLE 4.4 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA TEMPERATURE MARCH 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.16 -0.23 1.49 1.49 24 -0.23 -0.35 1.62 1.69 36 -0.28 -0.34 1.86 1.82 48 -0.26 -0.39 2.04 2.04 60 -0.26 -0.41 2.26 2.29 72 -0.32 -0.43 2.52 2.54 84 -0.34 -0.50 2.76 2.97 TABLE 4.5 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA TEMPERATURE MARCH 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.08 0.11 0.83 0.80 24 0.17 0.12 0.98 1.00 36 0.18 0.19 1.24 1.18 48 0.23 0.21 1.48 1.47 60 0.25 0.25 1.77 1.68 72 0.26 0.21 1.96 1.95 84 0.34 0.18 2.18 2.22 TABLE 4.6 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA TEMPERATURE MARCH 2011 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.83 0.76 1.33 1.28 24 1.05 0.98 1.65 1.58 36 1.18 1.12 1.91 1.83 48 1.29 1.21 2.17 2.14 60 1.35 1.25 2.43 2.37 72 1.32 1.30 2.64 2.55 84 1.30 1.33 2.72 2.78 # ** NCEP/USA NAM MODEL ** TABLE 4.7 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA WIND MARCH 2011 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.34 -0.56 3.99 3.97 24 -0.29 -0.34 4.33 4.39 36 -0.15 -0.22 4.95 4.87 48 -0.18 -0.37 5.43 5.48 60 -0.25 -0.35 6.01 6.18 72 -0.20 -0.54 6.71 7.05 84 -0.28 -0.36 7.44 7.82 TABLE 4.8 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA WIND MARCH 2011 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.59 -0.56 4.36 4.22 24 -0.49 -0.43 4.97 4.93 36 -0.71 -0.49 5.96 5.72 48 -0.62 -0.51 6.72 6.84 60 -0.82 -0.47 7.68 7.68 72 -0.66 -0.77 8.31 8.42 84 -1.01 -0.58 9.11 9.57 TABLE 4.9 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA WIND MARCH 2011 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.40 -0.40 5.07 4.96 24 -0.46 -0.58 6.28 6.16 36 -0.63 -0.72 7.55 7.56 48 -0.72 -1.04 8.74 8.87 60 -0.86 -1.10 10.39 10.16 72 -1.02 -1.29 11.72 11.91 84 -1.11 -0.87 12.90 13.30