VRAD: A Browser for NEXRADReflectivity Data

Anton Kruger

Witold Krajewski

Iowa Institute of Hydraulic ResearchThe University of Iowa

Why a Visualization Tool?

• Quality control - “have you looked at thedata?”

• Patterns that are difficult to anticipate orformalize are very easily recognized byhumans.

• Reanalysis of NEXRAD data - find interestingportions of rainfield.

Example 1

Notice how automatic quality control producedmissing reflectivity spokes

Example 2

Wind and seagenerated clutter

Example 3

Sun spike

Requirement for Tool

• It must provide rapid navigation

– Between any volume in the data set

– Between any sweep in a volume

• Must show PPI, RHI, and AHI.

• No polar-Cartesian remapping.

• Must be very easy to use (KIS).

• It is not an analysis tool.

A Virtual Radar (VRAD)

Menu

Legend

Navigationbuttons

Mode buttons

Browse window andslider

The Menus

Selecting a year

Selecting thebackground

Selecting a colormap

Selecting a site

Selecting abrowse statistic

Browse PPI Mode

Scan levelbrowsing

Browse PPI Mode (Up)

Not inbase scananymore

PPI and RHI Mode

RHI mode

Slicer

PPI and AHI Mode

AHI Mode

Slicer

VRAD’s Future

• Runs on HP-UX platform: should it be ported to

other platforms?

• What additional features (saving, printing, etc.)

are desirable?

• Q: What is the future of WATADS?

• A: WATADS needs VRAD and RLE

Animation (click on the image to play)