July-August 2017 registered 13.5% of all 889 reporting stations with 20-yr daily extreme precipitation events (5th highest since 1901), cementing a significant upward trend for this region in the contiguous US through 2017 (+2.5% per century, p=99.99%). There were two regions with noteworthy total counts: the South (22.1%; 3rd highest, mostly associated with Hurricane Harvey) and the Ohio Valley (16.1%; tied for 10th highest). While the South has not shown a significant trend in July-August, the Ohio Valley had seen a significant upward trend through 2016 with +3.1% per century (p=99.6%). In contrast, the Pacific Northwest recorded not a single 20-yr daily extreme, tied for lowest rank with 13 other years, but not associated with any significant trend.

There were two "Billion-Dollar Disaster" ( https://www.ncdc.noaa.gov/billions/events) during this season, but the first one was huge: Hurricane Harvey dropped record amounts of rain on Texas in late August, leading to at least 89 fatalities. Total damages in excess of $127B make this the biggest weather-related disaster in the US since Hurricane Katrina (2005), but also globally for 2017. The lack of rain in the northern plains since late spring arguably created the most severe drought since 1990 in that region, leading to losses in excess of $2B by the end of the year.