Increases in the Number of Days with Very Heavy Precipitation
The map shows the percentage increases in the average number of days with very heavy precipitation (defined as the heaviest 1 percent of all events) from 1958 to 2007 for each region. There are clear trends toward more days with very heavy precipitation for the nation as a whole, and particularly in the Northeast and Midwest. Image Source: updated from Groisman et al.1
- 1.  Groisman, P.Ya., R. W. Knight, D. R. Easterling, T. R. Karl, G. C. Hegerl, and V. N. Razuvaev. "Trends in Intense Precipitation in the Climate Record." Journal of Climate 18, no. 9 (2005): 1326-1350.