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Nexrad Question
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Author:  ddelprop [ Fri Dec 09, 2011 12:01 pm ]
Post subject:  Nexrad Question

I noticed that on the Nexrad base reflectivity image this morning, the label is marked as....
MODE B /31

As the scale max's out at 15, I assume Radar is not operating in Precipitation Mode. I noticed that the label did not change from when it was in Precipitation Mode a few days ago

So my question is what does Mode B / 31 designate?


Author:  ddelprop [ Fri Dec 09, 2011 1:23 pm ]
Post subject:  Re: Nexrad Question

Is this it ?.... From wikipedia
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 nine 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. The radar operator chooses from the VCPs based on the type of weather occurring:

Clear Air or Light Precipitation: VCP 31 and 32
Shallow Precipitation: VCP 21
Convection: VCP 11, 12, 121, 211, 212, and 221 [4]

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