How interested are you in getting this done? Below is a link to a phased array demonstrator (SPY-1A) that was dismantled and replaced with a newer version in 2016. Might find out where SPY-1A is sitting (the phased array may have been returned to the US Navy), and since it'll perform both weather and aircraft surveillance, might be easier to sell to stakeholders for the coverage gap.

https://www.nssl.noaa.gov/tools/radar/mpar/

Alternatively, Roberts Field appears to be a major commercial air hub in central Oregon. You might argue from a safety perspective to your Congressional representatives (perhaps in concert with local air carriers and AOPA) that the airport needs a TDWR station (cost will be ~$4MM-8MM), which could also provide NOAA with the necessary weather surveillance data. Thunderstorms aren’t common on the West Coast though, hence the lack of TDWR stations in West Coast states. If you pursue this route, you'd want to get funds for this into some sort of federal transportation bill, as part of enhancing the safety of the air transportation system.

https://en.wikipedia.org/wiki/Terminal_Doppler_Weather_Radar

I've mentioned it to our representative, Greg Walden, in the past, but he doesn't seem interested, which is a pity, because this is the kind of non-partisan stuff that they ought to be getting done for their constituents.

Maybe you could use microwave links in the cellular network instead? There's research and development going on in that area.

https://www.smhi.se/en/services/professional-services/microw...

That's cool! I can imagine that could be an excellent secondary data source for rainfall monitoring.

Having better weather insights for Smith Rock would be great. Saying hi from the a Monkey!