Storm prediction based on stability indices from the ALADIN numerical model

In this article, we follow up on our previous work focused purely on air sounding measurements. We are now incorporating vertical profiles from forecasts and analyses of the ALADIN model operated by the Czech Hydrometeorological Institute (ČHMÚ), and comparing these with actual measured soundings at corresponding times. In our earlier studies, we explored a wide range of instability indices – from simple historical indices, through combinations of multiple indices, to more complex physically relevant variables used mainly in recent decades. For a selected set of 17 indices, we have now calculated values from both model analyses and forecasts, and compared their ability to predict thunderstorm occurrence in the selected radius of the sounding station during the afternoon and early night hours. We focused both on comparing the predictive capability itself – such as against morning and midnight soundings – and on the reliability of forecasts from different runs of the ALADIN model, starting up to 72 hours before the key noon sounding marking the beginning of the evaluated time interval.