NWS Doppler Radar Dual Pol

Severe Weather and Heavy Rainfall from the High Plains to the Ohio Valley; Heat Continuing in the Central Plains and Southeast

A stationary front will be the focus for daily showers and thunderstorms capable of widely scattered flash flooding and severe weather from the High Plains to the Ohio Valley. Monsoonal thunderstorms could cause local flash flooding across the Southwest and the Great Basin. Dangerous heat continues across the Central Plains and Southeast. Many areas will see their hottest temperatures of the year. Read More >

NWS Doppler Radar (WSR-88D) Example Products

Conventional Doppler radar sends out a horizontal energy pulse providing a one dimensional view of precipitation. Dual pol radar sends both horizontal and vertical pulses, providing a two dimensional view. Thus, it provides much better information about the size, shape, and estimated amount of precipitation, distinguishing between rain, snow, and hail. Basic dual pol products include correlation coefficient (CC), differential reflectivity (ZDR), and specific differential phase (KDP). More information is available on our Dual Pol webpage.

Above, two clusters of thunderstorms had high base reflectivity values between 50 and 60 dBZ (upper left). Meanwhile, CC data (upper right) showed high values above 0.96 (dark red/purple) in the same area as the high reflectivity values. High CC indicates similarly-shaped precipitation vs. a mix of types (i.e., hail-rain mix). ZDR (lower right) depicted values of 3.0-5.0 in the same location, suggesting large hamburger bun-shaped rain drops. KDP (lower left), often used to assess heavy rain using dual pol data, showed values of 2.0-5.0 suggesting a large concentration of rain and large drops. The combination of CC, ZDR, and KDP all supported the occurrence of very heavy rainfall with large drops in the storms, and little or no hail. Reflectivity alone cannot be used to specifically identify the exact nature of precipitation type and size in a storm.

Severe Weather and Heavy Rainfall from the High Plains to the Ohio Valley; Heat Continuing in the Central Plains and Southeast

NWS Doppler Radar Dual Pol - Heavy Rain

NWS Doppler Radar (WSR-88D) Example Products