Pittsburgh NEXRAD Radar Going Dual-Pol

The Pittsburgh, Pennsylvania NEXRAD radar is going "Dual-Pol" after the July 4th holiday. What does this mean to you? Longer term, it means that new radar products will be available from the NWS and AccuWeather. According to the NWS Dual Polarization schedule, Pittsburgh is only the third radar in the nation to be upgraded. Dual-pol radars are capable of getting a vertical, as well as horizontal, slice of the atmosphere. With that information, they can do things like tell snow from hail, make more accurate precipitation estimates, and see tornadoes better on the ground at night.

The NWS in Pittsburgh has both a Press Release and a Web Page to give you more information. Below is an example of the precipitation type algorithm (radars like AccuWeather.com's Snow/Ice/Rain radar estimate precipitation type based on surface reports and upper air estimates, but this will increase accuracy when implemented nationwide). This will also be really handy when applying filters to get rid of what we call "non-meteorological products" -- such as insects, birds, and ground clutter. More information about dual polarization is available from the NWS in this PDF.

For the short-term, it means that you won't be able to view the Pittsburgh single-site radar maps, unfortunately, until mid-July because the radar has to be taken down for hardware and software maintenance by the U.S. National Weather Service to complete the upgrade (see their outage notice).

During this time, "composite" radar products from all vendors may also be inaccurate in that area (composites, such as AccuWeather.com's State & Metro radars and MapSpace, attempt to combine the data from all ~150 radar sites across the nation, but each radar can only see precipitation about 150 miles from the site, and detect rotation and severe weather about half that far). You can also use a neighboring NEXRAD site (such as the one here in State College, PA, see a list underneath our state radar image) if you are in its coverage area.