Mobile Alabama X-Band Radar (MAX)

Fabricated and added to the list of UAH facilities in 2008, the MAX platform became one of the first dual polarization mobile X-Band Doppler radars. MAX collected vital radar data over the years from landfalling tropical storms, boundary layer experiments, and tornado and severe weather. MAX has taken part in numerous field campaigns such as PLOWS (2009-2010), ABIDE (2011-2014), PECAN (2015), VORTEX-SE (2016-Present). Not only has MAX played an instrumental role in these field campaigns, but it has also provided valuable datasets outside of field campaigns from hurricane deployments to local deployments centered in the Tennessee Valley in support of local boundary layer (BL) and severe weather studies (Lake breeze experiments, convective and nocturnal BL experiments, tornadic and non-tornadic QLCSs).

MAX deployed at Courtland, AL for a VORTEX-SE IOP on 23 April 2020.

In recent years, the MAX has served a pivotal role as a wind profiling system through Velocity-Azimuth Display (VAD) scans and has been used in multi-Doppler networks with other mobile radars (NSSL SMART-R) and fixed-site radars such as WSR-88D or the UAH ARMOR to provide 3-D wind fields over a meso-beta domain.

The MAX system comes complete with an 8-ft dish with a 1-degree beam width, a 250-kW magnetron transmitter, Vaisala SIGMET RVP8 processor, Baron Radar Services dual polarization components, and a surface measurements tower providing wind, temperature, and RH at 10 meters. A Vaisala WXT-520 surface sensor is mounted at 5 meters that provides measurements such as pressure, wind, temperature/RH, and precipitation rate. MAX runs on two Linux-based computers and one Windows 10 computer that comes loaded with GR2Analyst for real-time data viewing and situational awareness. Four hydraulic leveling jacks located on the bed of the truck and 2 located on the front of the cab help keep the truck stable and level no matter the deployed location.

The MAX deployed for Hurricane Laura (2020). With all 6 jacks deployed, the cab remained stable during the high winds experienced.

All instruments and computers onboard MAX are powered by a diesel 10kW generator with a 16-gallon capacity. The fuel tank can be monitored and refilled from within the cab of the truck which reduces the amount of time personnel are required to leave the safety of the cab during deployments. The platform is built on the bed of an International 4300 truck with a fuel capacity of 140 gallons which allows for extended deployments without the need for timely refueling during the operations. The large crew cab of the truck allows for up to three personnel to work inside MAX comfortably.

  • Frequency: X-Band (9450 MHz)
  • Transmitter: Magentron
  • Polarization: Dual
  • Peak Transmit Power: 250 kW
  • Beamwidth: 0.95°
  • Antenna Size: 8ft
  • Variables Recorded: Z, V, W, ZDR, fDP, KDP, rhv, LDR
  • Receiver: RVP8

Wind profile produced by the MAX high resolution VAD detailing a frontal passage over the MAX site.

RHI from MAX of a BWER on 12 Feb 2020.

MAX deployed for Huricane Laura (2020).

Inside MAX operations during the PERiLS field campaign.