NWS to get a radar upgradeJanuary 26th, 2012 at 9:59 am by Natalie Stoll under Weather
There’s exciting news from the NWS Austin/San Antonio office in New Braunfels. They’ll upgrade their radar with dual-polarization this spring. The new technology will help meteorologists better determine what kind of precipitation exists in a storm.
That’s exciting for us because we use the national network of radars here in the First Warning Weather center in addition to our own radar to get a complete look of weather in our viewing area.
Here’s some information on the change from the NWS:
The exciting dual-polarization radar upgrade to the KEWX WSR-88D is scheduled for installation from March 19 through April 1, 2012! This upgrade will incorporate a new technology called dual-polarization, or dual-pol, that is part of the NWS vision to build a weather-ready nation to better protect lives and livelihoods. This new technology will result in 14 new radar products that will enable us to continue providing our suite of high quality products and services to the citizens of South Central Texas. This new technology and data primarily will help forecasters identify the type of precipitation that is falling as well as improve rainfall estimates.
We strongly encourage all users of these new products to complete a series of online training modules that were recorded by the Warning Decision Training Branch (WDTB). Modules are available for non-NWS meteorologists and non-meteorologists through this website.
What is dual-pol?
The current doppler radars transmit and receive pulses of radio waves in a horizontal orientation. As a result, the radar only measures the horizontal dimensions of targets (e.g. cloud and precipitation droplets). Dual-polarimetric radar transmits and receives pulses in both a horizontal and vertical orientation. Therefore, the radar measures both the horizontal and vertical dimensions of targets. Since the radar receives energy from horizontal and vertical pulses, we can obtain better estimates of the size, shape, and variety of targets. It is expected that this will result in significant improvements in the estimation of precipitation rates, the ability to discriminate between precipitation types (e.g. hail vs. rain), and the identification of non-meteorological returns.
- Improved accuracy of precipitation estimates, leading to better flash flood detection
- Ability to discern between heavy rain, hail, snow, and sleet
- Improved detection of non-meteorological echoes (e.g. ground clutter, chaff, anomalous propagation, birds, and tornado debris)
- Detection of aircraft icing conditions
- Identification of the melting layer (e.g. bright band)
Dual-Pol will not improve tornado lead times or be able to provide exact precipitation type on the ground.