Based on the data available from the Protezione Civile, which are daily updated (solid line with plus symbols: prediction; circles: observed data) by using:

• a standard SIR model until March 21, 2020;
  
  
• a multi-region SIR (mrSIR) model, starting from March 21, 2020. For this model, we have divided Italy into 3 macro-regions, depending on the onset of the epidemic and the geography:
• north (Emilia Romagna, Friuli Venezia Giulia, Liguria, Lombardia, Piemonte, Trentino, Valle d'Aosta, Veneto),
• center (Abruzzo, Lazio, Marche, Toscana, Umbria),
• south and islands (Basilicata, Calabria, Campania, Molise, Puglia, Sardegna, Sicilia).
• N.B.: starting from April 19, 2020, we have treated separately Lombardy, removing it from the north macro-region;

• a multi-region SI₂R₂ (mrSI₂R₂) model, starting from April 21, 2020, with Italy divided in the previous 4 macro-regions (Lombardy, north, center, south and islands).
  A very special thank goes to Paolo Zanzottera, for the fruitful discussions to properly tune the mrSI₂R₂ model.
  We also report the forecasts obtained by using this model starting from April 1, 2020, in order to compare them with those of the previous mrSIR model.