Weather radar facts for kids

A weather radar is a type of radar used to show where precipitation is. Weather radar can tell the movement of precipitation, what type it is (rain, snow, hail, etc.), and forecast its future.

Modern weather radars are mostly Doppler radars, which can find the movement of rain drops and the intensity of the precipitation. Both types of information can be used to find the structure of storms and tell if they will cause any severe weather.

Images for kids

David Atlas
Scanned volume by using multiple elevation angles
Idealized example of Doppler output. Approaching velocities are in blue and receding velocities are in red. Notice the sinusoidal variation of speed when going around the display at a particular range.
Base PPI versus Composite.
Map of the RIDGE presentation of 2011 Joplin tornado.
A supercell thunderstorm seen from two radars almost colocated. The top image is from a TDWR and the bottom one from a NEXRAD.
Reflectivity (left) and radial velocities (right) southeast of a NEXRAD weather radar. Echoes in circles are from a wind farm.
Example of strong attenuation when a line of thunderstorms moves over (from left to right images) a 5 cm wavelength weather radar (red arrow). Source: Environment Canada
Radar image of reflectivity with many non-weather echoes.
The same image but cleaned using the Doppler velocities.
Phased Array Weather Radar in Norman, Oklahoma
Weather radar on the wing of Pilatus PC-12
Nowcasting a line of thunderstorms from AutoNowcaster system
NOAA NEXRAD radar image of the Park Forest, IL, meteorite fall of 26 March 2003.
Weather radar in Norman, Oklahoma with rainshaft
Weather (WF44) radar dish
University of Oklahoma OU-PRIME C-band, polarimetric, weather radar during construction
1960s radar technology detected tornado producing supercells over the Minneapolis-Saint Paul metropolitan area.
Maximum range from reflectivity (red) and unambiguous Doppler velocity range (blue) with pulse repetition frequency
Radial component of real winds when scanning through 360 degrees
Typical angles scanned in Canada. The zigzags represent data angles used to make CAPPIs at 1.5 km and 4 km of altitude.
24 hours rain accumulation on the Val d'Irène radar in Eastern Canada. Notice the zones without data in the East and Southwest caused by radar beam blocking from mountains.
Berrimah Radar in Darwin, Northern Territory Australia
The square in this Doppler image has been automatically placed by the radar program to spot the position of a mesocyclone. Notice the inbound/outbound doublet (blue/yellow) with the zero velocity line (gray) parallel to the radial to the radar (up right). It is noteworthy to mention that the change in wind direction here occurs over less than 10 km.
PPI reflectivity loop (in dBZ) showing the evolution of a hurricane
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Profiler high resolution view of a thunderstorm (top) and by a weather radar (bottom).
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The strong echoes are returns of the central peak of the radar from a series of small hills (yellow and reds pixels). The weaker echoes on each sides of them are from secondary lobes (blue and green)
1.5 km altitude CAPPI at the top with strong contamination from the brightband (yellows). The vertical cut at the bottom shows that this strong return is only above ground.
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