https://www.washingtonpost.com/weather/2019/11/22/global-g-deal-poses-significant-threat-weather-forecast-accuracy-experts-warn/

A long-awaited international deal governing how the world’s
technology companies should roll out 5G technology poses serious risks to
weather forecast accuracy, according to data from federal agencies and the World
Meteorological Organization.

Studies completed before the negotiations by U.S. government agencies such as
the National Oceanic and Atmospheric Administration, NASA and the Navy had
warned that 5G equipment operating in the 24-gigahertz frequency band could
interfere with transmissions from polar-orbiting satellites used to gather
weather data. This could make forecasts much less reliable, the reports found.

Specifically, these highly technical analyses concluded that if deployed widely
and without adequate constraints, telecommunications equipment operating in the
24 GHz frequency band would bleed into the frequencies that NOAA and NASA
satellite sensors also use to sense the presence and properties of water vapor
in the atmosphere, significantly interfering with the collection and
transmission of critical weather data.

The NOAA report, for example, warned of a potential loss of 77.4 percent of data
coming from microwave sounders mounted on the agency’s polar-orbiting
satellites.

Going into the negotiations in Egypt, the United States took a negotiating
position that was extremely concerning to scientists at NOAA and NASA, because
it called for a limit of up to -20 decibel watts of interference (the lower the
limit, the more buffer room there is). European regulators and the World
Meteorological Organization, a U.N. agency, took a stricter line, arguing for
stricter interference limits of up to -55 decibel watts.

The newly agreed standard represents a middle ground and will be introduced in
two stages. The first stage, which will be in effect until Sept. 1, 2027, will
be -33 decibel watts, and this will tighten to -39 decibel watts after that.

If you've ever used a 2 meter radio, you know what this is about.