Rain Accumulation Calibrations Follow

A default calibration is used for haptic rain sensors in the Tempest and SKY devices. The haptic rain sensor detects and quantifies rain using vibration signals - not directly by volume or weight. There are many factors that can influence vibration signals. Each and every haptic sensor in the field is subject to unique external factors that can contribute to accumulation discrepancies, for example, mount materials, mast height, environment, wind, and turbulence can all affect the resulting rain accumulation readings.

Haptic Rain Sensor Calibration

Field calibration can help improve accuracy of the haptic sensor readings if accumulation measurements are way outside of accuracy specifications. Due to the factors that contribute to different vibration signatures, calibrations may need to be applied in the field, after final installation. You should first ensure that your mount is sturdy and there are no external vibration contributing to over-reporting accumulation. Calibration cannot fix the effects of an unstable mount or random vibrations caused by winds, birds, etc.

Haptic rain sensor calibrations can be updated using comparison rain data. If you think your device needs an adjustment, please follow the instructions below...

• I have another rain gauge I can use for comparison data.

The best and most successful method of calibration is to use accumulation readings from another trusted gauge that is on the same property. 

1. First, follow this link to register the other rain gauge you will be using for comparison data.
2. Once registered, follow this link to report individual rain events.
   • Reports should be submitted over a 24-hour period, from 12AM to 12AM local time.
   • More data from a larger sample size of rain events is preferred.
   • Use comparison data from at least several precipitation events with varying intensity for the best results.
3. Follow up with us after you think you have submitted enough reports for a calibration adjustment.

• I do not have access to another gauge. Can I still get a calibration adjustment?

We can use data published online from nearby gauges and/or Nearcast Rain values to help with calibration adjustments. If there is another trusted weather station nearby that is reporting data online, we can review the data to use as a reference for calibration. Please contact us for assistance and let us know what other rain measurement source you're using for comparison.