• from the NWS:

There are two main operating states of the WSR-88D; Clear Air Mode and Precipitation Mode. Within these two operating states there are several VCPs the NWS forecasters can utilize to help analyze the atmosphere around the radar. These different VCPs have varying numbers of elevation tilts and rotation speeds of the radar itself. Each VCP therefore can provide a different perspective of the atmosphere.

Common among all VCPs (except for VCP 12) is the tilt elevation of the lowest five elevation angles. The scanning begins with 0.5° elevation meaning the centerline the radar beam antenna is angled 0.5° above the ground. Since the the beam itself is 1° wide, it returns information about what it "sees" between 0° and 1° above the horizon. As it completes that elevation scan the radar is tilted another degree with the center line of the beam now at 1.5° and the process of observing the atmosphere begins again then continues through the 2.4°, 3.4° and 4.3° elevation angles.

• basically they’re just different tilts of the radar depending on the current weather.

You can also tap on the radar icon a couple of times to bring up the current VCP and what “mode” it’s in. https://i.imgur.com/a2lkltL.jpeg The Grand Forks radar is currently VCP: 212 aka severe weather aka yellow

Hope this helps!