You depend on forecasters to keep you informed on current and future weather conditions. Forecasters depend on radars to see inside the weather so you get the most accurate and up-to-date information.
Radar provides valuable clues about what kinds of precipitation to expect and which way a storm is moving. That’s why NOAA scientists helped develop the WSR-88D radars, also known as NEXRAD, which send out horizontal pulses providing information about snow, ice pellets, hail, and rain particles. These radars also can tell which direction the wind is moving – it can see rotation and other severe weather patterns before it affects us on the ground! The information provided by Doppler radars has saved a significant number of lives by giving us a “heads-up” to severe weather.
Making Good Radars Better
Not satisfied with good, NOAA scientists continue to scrutinize radar technology to make it faster and better. One recent discovery was that if a radar radio wave could be sent out horizontally and vertically (dual-polarization), hazardous weather forecasts and warnings would drastically improve. We found we could better estimate the amount of precipitation that was falling, and tell the difference between very heavy rain and hail improving flash flood watches and warnings. This discovery is so important that all of
NOAA’s National Weather Service radars will be upgraded with dual-polarization starting in 2010.
The Future of Weather Radar
Thousands of beams of energy piercing the sky at one time…it’s the future of weather radar! Phased array radar technology – once used on Navy ships, has the potential to increase tornado warning lead times, detect unresponsive aircraft, and serve as back-up air traffic control. The phased-array research radar, known as the National Weather Radar Testbed, has been operational since 2003, and researchers have been putting it through intense testing ever since. Already the NWRT has shown it can detect rapidly evolving weather phenomena such as tornadoes and microbursts, potentially extending warning lead times for severe weather. As our nation’s legacy radars age, NOAA researchers are looking to the future to address current and anticipated radar needs. Researchers envision a multifunction phased array radar, with its versatility and adaptive scanning capability, which promises to address a wide variety of national surveillance needs for both weather and aircraft.
Up Close and Personal
Rather than waiting for a storm to come to them, NOAA scientists sometimes have to track down elusive storms with mobile radars. These shared radars can rapidly scan the atmosphere at low levels, below the beam of NEXRAD radars, to collect data on the storms. In areas where mountains block the beams of the regular radars, mobile radars have been shown to be helpful in providing extra rainfall data to determine the threat of flash floods and debris flows.
Radar is one of the most valuable tools in a forecaster’s arsenal. And NOAA continues to use ingenuity and creativity to push radar technology to the edge and beyond. 
