I live within 100 feet of one of these very-capable municipal rain gauges, would be nice to be able to key off that data.
These numbers are integrated into GIS data as I can pull them up on the ESRI ArcGIS app. So there is probably some way to use location of Iro controller to pick one or a few to use - programmatically. Unfortunately I bet not many municipalities do this type of thing...and probably not in a standard way...for it to be a viable source of data.
There are also private weather stations around here that feed data to weather underground (maybe a more-ubiquitous data source).