Fig. 3: Time series of spatially averaged precipitation.

The averaging domain for each event is defined by the grid points where the observed hourly precipitation exceeded 5 mm at the time of maximum hourly precipitation recorded at the surface stations. a–g correspond to the 202108 event, h–n to the 202007 event, and o–u to the 201009 event. The first row (a, h, o) represents the observational data derived from the KMA 500 m dataset. The second to fourth rows show the model experimental results. In the model panels, the left column (b, d, f, i, k, m, p, r, t) presents results from simulations with spectral nudging, whereas the right column (c, e, g, j, l, n, q, s, u) presents results without spectral nudging. In the observational data panels, the blue bars represent hourly precipitation, and the green line indicates 24-h accumulated precipitation. The blue dotted line marks the timing (x-axis) and magnitude (y-axis) of the maximum observed hourly precipitation, and its value is displayed in the upper-left text. In the model panels, the pink marker indicates the timing and magnitude of maximum hourly precipitation in the model simulation. The shading represents the range of ensemble members in the model results.