Terry’s Take: Duel-pol…new fangled radar now in place!

Posted on: 3:19 pm, April 29, 2013, by , updated on: 10:41pm, April 30, 2013

Terry Swails Weather Blog

This week, the National Weather Service completed work on the dual-polarization technology update – ending the upgrade process of 122 NWS radar sites throughout the country (including ours in the Quad Cities). This new advanced technology is helping weather forecasters more accurately track, assess and warn the public of approaching high-impact weather.

The radar receiving dish inside the protective cover

The radar receiving dish inside the protective cover

Dual-polarization is the most significant enhancement made to the nation’s federal weather radar system since Doppler technology was first installed in the early 1990s. Dual-pol radar sends and receives both horizontal and vertical pulses, which produces a much more informative picture of the size and shape of the objects in the sky. This provides meteorologists the ability to distinguish between rain, snow, hail and non-weather items like wildfire smoke plumes, birds and insects. Conventional Doppler radar only has a one-dimensional view making it difficult to tell the type of precipitation or object in the sky.

Dual-pol data shows what type of precipitation is falling based on its shape

Dual-pol data shows what type of precipitation is falling based on its shape

Dual-pol technology can also identify non-weather targets such as bugs, bats or debris from a tornado producing damage

Dual-pol technology can also identify non-weather targets such as bugs, bats or debris from a tornado producing damage

This game-changing technology has already helped forecasters issue more accurate and timely warnings to the public and has saved lives.” Dual-pol is credited with providing improved detection of heavy rainfall, which can increase warning time for flash floods. During winter storms, forecasters use dual-pol information to monitor a transition from snow to sleet and freezing rain, which allows for a more accurate forecast. Dual-pol can also spot airborne debris giving forecasters the ability to confirm a tornado on the ground, even in the dark or when hidden by heavy rain.

No doubt, forecasts and warnings will be more accurate and timely thanks to this “new fangled” brand of radar.

Dual-polarization is the most significant enhancement made to the nation’s Next Generation Weather Radar network, NEXRAD, since Doppler radar was first installed in the early 1990s.

Dual-polarization is the most significant enhancement made to the nation’s Next Generation Weather Radar network, NEXRAD, since Doppler radar was first installed in the early 1990s.