VERIFICATION TO W.M.O. STANDARDS ---------------------------------------- N.C.E.P./U.S.A. DECEMBER 2009 ------------------------------------------------ NORTH AMERICAN MODEL (NAM) ----------------------------------- # ** NCEP/USA NAM MODEL ** TABLE 4.1 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA GEOPOTENTIAL HEIGHT DECEMBER 2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -3.49 -2.80 8.62 8.54 24 -3.73 -3.13 10.09 10.37 36 -4.74 -4.05 13.24 13.22 48 -4.78 -4.56 15.93 16.32 60 -5.58 -5.24 19.83 20.25 72 -7.54 -5.38 25.38 24.53 84 -7.12 -5.29 30.08 29.88 TABLE 4.2 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA GEOPOTENTIAL HEIGHT DECEMBER 2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -4.32 -3.05 10.88 10.69 24 -4.01 -4.09 13.09 13.93 36 -4.45 -4.50 17.38 18.29 48 -4.44 -4.89 22.20 23.65 60 -5.61 -5.58 29.23 29.46 72 -6.39 -4.51 36.85 36.06 84 -7.39 -4.69 42.45 43.87 TABLE 4.3 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA GEOPOTENTIAL HEIGHT DECEMBER 2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 1.51 2.18 14.41 13.56 24 4.68 2.75 19.78 18.93 36 6.32 4.76 25.20 25.04 48 8.13 6.49 32.35 31.50 60 6.93 7.19 39.86 38.82 72 7.67 7.08 48.88 48.24 84 5.31 7.44 57.68 58.27 # ** NCEP/USA NAM MODEL ** TABLE 4.4 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA TEMPERATURE DECEMBER 2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.02 0.00 1.49 1.52 24 -0.01 -0.03 1.64 1.65 36 0.05 0.05 1.79 1.85 48 0.10 0.10 2.06 2.05 60 0.06 0.12 2.30 2.30 72 0.06 0.11 2.67 2.62 84 0.12 0.19 2.87 3.04 TABLE 4.5 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA TEMPERATURE DECEMBER 2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.15 0.13 0.92 0.92 24 0.21 0.09 1.13 1.16 36 0.26 0.17 1.36 1.41 48 0.34 0.28 1.63 1.63 60 0.39 0.30 1.86 1.84 72 0.40 0.32 2.19 2.11 84 0.35 0.36 2.43 2.39 TABLE 4.6 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA TEMPERATURE DECEMBER 2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.71 0.73 1.30 1.30 24 0.85 0.75 1.55 1.51 36 0.84 0.80 1.77 1.70 48 0.94 0.84 1.98 1.93 60 0.84 0.86 2.16 2.12 72 0.91 0.84 2.41 2.29 84 0.88 0.80 2.57 2.49 # ** NCEP/USA NAM MODEL ** TABLE 4.7 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA WIND DECEMBER 2009 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.41 -0.49 3.87 4.01 24 -0.34 -0.35 4.32 4.34 36 -0.31 -0.39 4.77 4.73 48 -0.44 -0.35 5.29 5.32 60 -0.49 -0.45 5.92 5.91 72 -0.58 -0.59 6.64 6.64 84 -0.66 -0.47 7.30 7.29 TABLE 4.8 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA WIND DECEMBER 2009 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.59 -0.62 4.46 4.33 24 -0.46 -0.53 5.16 5.20 36 -0.51 -0.66 6.26 6.20 48 -0.50 -0.62 7.33 7.22 60 -0.68 -0.75 8.47 8.61 72 -0.78 -0.69 9.63 9.53 84 -0.84 -0.73 10.75 10.52 TABLE 4.9 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA WIND DECEMBER 2009 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.59 -0.58 5.63 5.53 24 -0.79 -0.76 7.06 6.82 36 -0.95 -0.97 8.33 8.24 48 -1.18 -1.15 9.80 9.73 60 -1.48 -1.43 11.28 11.23 72 -1.48 -1.64 12.88 13.22 84 -1.74 -1.75 14.73 14.40