VERIFICATION TO W.M.O. STANDARDS ---------------------------------------- N.C.E.P./U.S.A. MAY 2009 ------------------------------------------------ NORTH AMERICAN MODEL (NAM) ----------------------------------- # ** NCEP/USA NAM MODEL ** TABLE 4.1 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA GEOPOTENTIAL HEIGHT MAY 2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.40 0.23 8.49 7.95 24 0.54 0.91 9.45 9.46 36 -0.58 0.88 11.03 10.83 48 -0.57 -0.51 12.13 13.25 60 -2.02 -0.81 15.99 14.13 72 -1.85 -1.69 17.46 18.56 84 -1.51 -1.51 21.37 19.80 TABLE 4.2 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA GEOPOTENTIAL HEIGHT MAY 2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -1.68 -0.35 9.95 9.56 24 -0.19 -0.18 11.15 11.54 36 -1.12 0.27 14.03 13.56 48 -0.33 -0.84 16.31 16.89 60 -1.90 -1.16 20.58 19.07 72 -1.73 -1.09 24.11 25.62 84 -1.72 -1.75 31.10 27.46 TABLE 4.3 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA GEOPOTENTIAL HEIGHT MAY 2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (M) (M) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 6.95 8.63 14.87 15.34 24 11.05 10.86 19.25 19.73 36 13.86 14.24 25.08 24.77 48 16.76 15.62 29.31 31.10 60 16.39 17.76 35.93 34.68 72 19.03 18.50 41.32 43.74 84 18.98 19.32 50.74 46.46 # ** NCEP/USA NAM MODEL ** TABLE 4.4 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA TEMPERATURE MAY 2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.05 -0.09 1.31 1.31 24 -0.05 -0.17 1.42 1.44 36 -0.11 -0.15 1.60 1.61 48 -0.09 -0.20 1.74 1.81 60 -0.15 -0.16 1.94 1.94 72 -0.16 -0.23 2.14 2.28 84 -0.25 -0.29 2.50 2.45 TABLE 4.5 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA TEMPERATURE MAY 2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.25 0.31 0.91 0.88 24 0.33 0.28 1.00 1.01 36 0.36 0.37 1.17 1.17 48 0.47 0.41 1.31 1.36 60 0.50 0.47 1.52 1.48 72 0.55 0.50 1.72 1.70 84 0.56 0.55 1.93 1.83 TABLE 4.6 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA TEMPERATURE MAY 2009 ------------------------------------------------ FORECAST MEAN ERROR RMSE PERIOD (K) (K) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 0.85 0.89 1.23 1.26 24 1.00 1.01 1.43 1.48 36 1.18 1.15 1.72 1.67 48 1.30 1.28 1.91 1.90 60 1.36 1.44 2.06 2.11 72 1.48 1.49 2.26 2.27 84 1.48 1.56 2.35 2.38 # ** NCEP/USA NAM MODEL ** TABLE 4.7 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 850 HPA WIND MAY 2009 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.40 -0.52 3.89 3.89 24 -0.34 -0.30 4.14 4.21 36 -0.27 -0.26 4.53 4.58 48 -0.35 -0.26 4.83 5.17 60 -0.29 -0.32 5.51 5.39 72 -0.29 -0.31 5.74 6.37 84 -0.40 -0.29 6.39 6.72 TABLE 4.8 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 500 HPA WIND MAY 2009 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.53 -0.41 4.18 3.97 24 -0.36 -0.22 4.48 4.64 36 -0.49 -0.36 5.26 5.13 48 -0.41 -0.38 5.84 5.98 60 -0.67 -0.43 6.76 6.19 72 -0.62 -0.60 7.30 7.25 84 -0.53 -0.46 8.08 7.81 TABLE 4.9 NORTH AMERICA VERIFICATION AGAINST RADIOSONDES -------------------------------------------------- 250 HPA WIND MAY 2009 ------------------------------------------------ FORECAST MEAN SPEED ERROR RMSEV PERIOD (M/S) (M/S) (HOURS) 00 GMT 12 GMT 00 GMT 12 GMT -------- ------ ------ ------ ------ 12 -0.19 -0.47 5.31 5.24 24 -0.53 -0.59 6.34 6.42 36 -0.44 -0.68 7.61 7.30 48 -0.53 -0.91 8.36 8.58 60 -0.77 -0.82 9.97 9.25 72 -0.61 -1.05 10.79 11.13 84 -0.67 -0.95 12.40 11.77