An analysis of Montreal's record-breaking heavy rainfall event of 8-9 November 1996, and a comparison with its best analogue /

Abstract

Montreal's heavy precipitation event of 8--9 November 1996 was noteworthy for its all-time record-breaking 24-hour accumulation of 134.0 mm. We analyse this case through a study of the synoptic-scale and mesoscale states.Searches for the best analogues to this event are conducted. Fields of the best mass analogue, for 1977, are compared to those of the 1996 event.It is found that, in the Montreal area, the 1996 event had persistently larger precipitable water content and synoptic-scale ascent values. Averaging the storm-total precipitation values of five randomly-chosen Montreal-area stations yields a value of 74.8 mm for this event. The analogue case, despite its excellent synoptic-scale similarity, was characterised by an average value of only 20.2 mm