NOAA, NASA, and the Navy have raised concerns with Congress that the new 24 GHz radio frequency band for 5G may interfere with critical water vapor sensors on US weather satellites. The 24 GHz band is one several new mmWave bands the FCC is making available for mmWave 5G service. Verizon and AT&T are deploying 5G this year in the 28 and 39 GHz mmWave bands. The FCC's auction of the 24 GHz band is expected to conclude on May 28th. The weather sensors in question operate at 23.8 GHz. The new 24 GHz band being auctioned spans 24.25 — 25.25 GHz. Even though the frequencies do not overlap, it is possible for adjacent radio signals to interfere due to "out-of-band emissions". NOAA claims the interference could reduce the accuracy of weather forecasts by up to 30%. The FCC and CTIA (the industry group that represents American cellular companies) both claim that such interference isn't possible.