PREDICTABILITY OF A STRONG PRECIPITATION EVENT; A CASE STUDY AND AN INVESTIGATION OF MODEL SENSITIVITY

For a convective event, simulated rainfall intensity is compared to the observations at a minute-time-scale. Temporal intermittency and peak intensities are found to be similar to the rain-gauge data, when the model is forced with analysis at the lateral boundaries. Predictability of the same event, estimated on the basis of several simulations starting on different initial large-scale analysis and with forecast lateral boundary conditions, is found to be very low, meaning that accurate predictions of this and similar events at 36 — 48 hour ranges are unlikely