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Unlike its predecessors, the WSR-88D antenna is not directly controllable by the user. Instead, the radar system continually refreshes its three-dimensional database via one of several predetermined scan patterns. Since the system samples the atmosphere in three dimensions, there are many variables that can be changed, depending on the desired output. There are currently six Volume Coverage Patterns (VCP) available to NWS meteorologists. Each VCP is a predefined set of instructions given to the antenna that control the rotation speed, transmit/receive mode, and elevation angles. They use a specific numbering scheme:

Clear Air: VCP 31 and 32 (two digits beginning with 3)
Shallow Precipitation: VCP 21 (two digits beginning with 2)
Convection: VCP 11 and 12 (two digits beginning with 1)
Multiple Pulse Frequency Dealiasing: VCP 121 (three digits beginning with a 1, followed by the 2 digit number of VCP with similar elevation angles)

CP	Scan Time (min)	Elevation angles (°)	Usage	Special attributes
11	5	0.5, 1.5, 2.4, 3.4, 4.3, 5.3, 6.2, 7.5, 8.7, 10, 12, 14, 16.7, 19.5	Convection, especially when close to the radar	Has the best overall volume coverage.
12	4	0.5, 0.9, 1.3, 1.8, 2.4, 3.1, 4.0, 5.1, 6.4, 8.0, 10.0, 12.5, 15.6, 19.5	Convection, especially activity at longer ranges	Focuses on lower elevations to better sample the lower levels of storms.
121	5.5	0.5, 1.5, 2.4, 3.4, 4.3, 6.0, 9.9, 14.6, 19.5	Large number of rotating storms, tropical systems, or when better velocity data is needed.	Scans lower cuts multiple times with varying pulse repetitions to greatly enhance velocity data.
21	6	0.5, 1.5, 2.4, 3.4, 4.3, 6.0, 9.9, 14.6, 19.5	Shallow precipitation	Rarely used for convection due to sparse elevation data and long completion time.
31	10	0.5, 1.5, 2.5, 3.5, 4.5	Detecting subtle boundaries or wintry precipitation	Long-pulse
32	10	0.5, 1.5, 2.5, 3.5, 4.5	Slow rotation speed allows for increased sensitivity. Default clear-air mode, reduces wear on antenna.	Short-pulse