Flood Risk and Vulnerability Analysis Project - Atlantic Climate ...

Storm Duration
Storm Duration
Storm Duration
Development of Projected Intensity-Duration-Frequency Curves
for Corner Brook and Goulds/Petty Harbour, Newfoundland May 16, 2012
Table 5-12 - St. John's Composite Record, Updated March 2012 Projected IDF Tables, 2020 Time
Period, Precipitation intensities over the specified duration, mm/hr
Maximum, 2020 timeframe
Return period (years)
2 5 10 20 50 100
5 min 57.9 76.3 88.4 100.1 115.3 126.6
10 min 45.5 58.1 66.3 74.5 85.1 92.7
15 min 39.2 50.0 57.1 63.7 72.8 79.5
30 min 29.7 37.7 43.0 48.3 54.7 59.7
1 hr 21.7 27.7 31.6 35.3 40.1 43.6
2 hr 14.9 19.6 22.6 25.5 29.2 32.1
6 hr 8.3 10.5 12.0 13.4 15.2 16.6
12 hr 5.3 6.7 7.7 8.7 9.9 10.8
24 hr 3.2 4.0 4.5 5.0 5.6 6.1
90th Percentile, 2020 Time Period
Return period (years)
2 5 10 20 50 100
5 min 57.1 75.6 87.7 99.5 114.7 126.1
10 min 44.6 57.4 65.6 73.8 84.5 92.1
15 min 38.5 49.4 56.4 63.1 72.2 78.9
30 min 28.9 37.0 42.3 47.6 54.1 59.2
1 hr 21.1 27.1 30.9 34.7 39.5 43.1
2 hr 14.5 19.1 22.2 25.1 28.8 31.6
6 hr 8.0 10.2 11.7 13.1 14.9 16.3
12 hr 5.1 6.5 7.6 8.5 9.7 10.6
24 hr 3.1 3.9 4.4 4.9 5.5 6.0
Mean, 2020 Time Period
Return period (years)
2 5 10 20 50 100
5 min 56.2 74.8 87.0 98.9 114.2 125.6
10 min 42.6 55.5 63.9 72.2 83.0 90.7
15 min 36.6 47.7 54.8 61.6 70.7 77.5
30 min 27.1 35.3 40.6 46.0 52.6 57.7
1 hr 19.5 25.5 29.4 33.2 38.0 41.6
2 hr 13.4 18.1 21.1 24.0 27.7 30.5
6 hr 7.5 9.7 11.2 12.6 14.4 15.8
12 hr 4.7 6.1 7.1 8.0 9.3 10.2
24 hr 2.8 3.6 4.1 4.6 5.2 5.7
AMEC Environment & Infrastructure 39