Radiosonde stations, profiles, and comparison with the model results. (a) Radiosonde stations used in the analysis. (b) Temperature profiles at the stations shown by the filled circles in (a) at 1200 UTC 20 February 2009. Profiles are resampled every 10 m in the vertical direction, and running means over 101 points are taken. The bottom scale is for the southmost profile, and other profiles are shifted 15°C each from south (left) to north (right). The markers show the tropopauses. (c) Scatter diagram of observed (the horizontal axis) and simulated (the vertical axis) . All the stations in (a) are analyzed from 0000 UTC 20 to 0000 UTC 21 February 2009, and data with the tropopause height below 14 km are plotted. Temperature profiles are smoothed as in (b).