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The NCAS X-band radar continuously measures precipitation throughout the day and night. Every 6 minutes, the software produces a graphic to visualise the data the radar collects.

The image above is the latest data collected by the X-band radar in Cumbria. A new image is created every 6 minutes and will be updated above soon after. There is a small delay between the latest image and the current time due to the time it takes for data to be transferred over a satellite connection from Cumbria to our servers at the University of Leeds. Sometimes, there is a large delay between the latest image and the current time because the radar is being stowed for safety reasons.

Most radars operate with a radome, a protective cover to shield the antenna from strong winds and hail. The NCAS mobile radar does not have a radome and therefore the maximum wind speed it can safely operate up to is 55mph. Once the winds reach this level, the motors are no longer able to work against the force of the wind, so there could be a risk of damage. For this reason, we stow (park) the radar, until the winds have weakened.

The X-band radar transmits pulses of electromagnetic radiation into the atmosphere and measures the amount of energy reflected back. Energy is reflected back when it hits precipitation particles, like rain droplets or snow. The amount of energy reflected is proportional to the number and size of the precipitation particles. The energy measured is termed the ‘reflectivity’ and is measured in units of dBZ. The more energy being reflected, the larger the dBZ measurement and the heavier the precipitation. 

After a short period of calibration and product development is completed, the plots will be displayed using a scale of mm of precipitation per hour (mm/hour).

This information is being used for research purposes only. For real-time operational radar data, you can visit the Met Office rainfall radar map.