Geoscience Reference
In-Depth Information
Figure 4.12
Maximum expected precipitation (mm) for storms of one-hour and twenty-four-hour duration occurring once in ten
years and once in 100 years over the continental United States, calculated from records prior to 1961.
Source
: US National Weather Service, courtesy NOAA.
Figure 4.13
The relationship between
area (km
2
) and frequency of occurrence,
during a five-year period, of rainstorms
that produce (A) 25-year and (B) 100-
year or heavier rain amounts for six- to
twelve-hour periods over 50 per cent
or more of each area in Illinois.
Source
: Chagnon (2002), by permission of
the American Meteorological Society.
10
5
2
1
A
0.5
B
0.2
0.1
10
20
50
100
200
500
1000
2000
5000
10,000
Area (km
2
)
