List of figures

Fig. 1. Studied basins (purple) and streamflow gauge (black dots) in southern Quebec province. 1:  Acadie, 2:  Nicolet, 3:  Bécancour, 4:  Famine, 5:  Beaurivage, 6: Etchemin, 7:  Matawin, 8:  Ouelle, 9:  Bras du Nord, 10:  Batiscan, 11:  York, 12:  Godbout. Basins IDs are ranked from south to north according to the latitude of basin centroids.

Fig. 2. Spring flood window from March to June and pre-event analysis period. The thick vertical stippled lines indicate the automatically detected flood onset date the peakflow date. The pre-flood analysis period extends from the onset date to one day before the peakflow date, to account for transfer times. Black curve: streamflow; blue bars: rainfall (P); red line: snowmelt (M).

Fig. 3. Interannual variability of flood magnitude and timing observed in the 12 study basins. (a) Peak streamflow (Q_max , mm/day); (b) peakflow timing (Q_maxT , in day of year) Basins are ranked by latitude, from south (ID#1) to north (ID#12). 1: Acadie, 2: Nicolet, 3: Bécancour, 4: Famine, 5: Beaurivage, 6 : Etchemin, 7: Matawin, 8: Ouelle, 9: Bras du Nord, 10: Batiscan, 11: York, 12: Godbout

Fig. 4. Boxplots showing the distribution of (a) the snowmelt volume (black) and rainfall volume (grey) in the pre-flood period for each basin and (b) the relative contribution of these volumes to the total runoff volume during this period. Basins are ranked by latitude, from south (ID#1) to north (ID#12).

Fig. 5. Correlogram showing Pearson’s linear correlation coefficient for all antecedent factors (columns) and spring flow peak magnitude (Q_max ) for the twelve basins (rows). Significant correlations (p  < 0.05) are highlighted in bold; blue colors indicate negative correlations and brown colors positive correlations.