Interesting. With respect to Harvey, my gauges in Bee County, Texas recorded highly variable amounts during August 25-28. The highest was about 6.5" (the gauge overflowed). A gauge a few feet away recorded about 3.5". These two were about 10 feet away from my house. The gauge I rely upon, which is situated away from all buildings, recorded 5.2". The NOAA radar readings for this area of Bee County showed between 1 and 1.5". I’ve noticed such discrepancies in other rainstorms featuring winds of about 50 mph (Harvey’s center never got closer than about 30 miles from where I live). Meteorologists have told me wind doesn’t make a difference as long as the instruments are in the open. I think high wind can distort readings even when instruments are farther away than most instruments are from structures.
Additionally, the extreme flooding around Houston has a lot to do with the paving and buildings, which have tremendously reduced the available soil that can absorb water.
The science involved in rainfall appears to me to be fraught with difficulties. This impacts the credibility of claims identifying global warming as a prime cause of excessive rainfall. However, I am convinced that global warming is making a big difference. We have to be aware of all the things affecting what we perceive about climate change.