Rain Accumulation values are calculated over a 24 hour period from midnight to midnight using the station's local time. Be cautious when comparing rain accumulation readings to other sources, collection times may differ and rain does not fall evenly across regions, towns or even neighborhoods.
A default calibration is used for haptic rain sensors in the Tempest and SKY devices. The haptic rain sensor detects and quantifies rain through vibrations not directly by volume or weight and so, there are many factors that can influence the readings. 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 rain accumulation readings.
When well sited and calibrated, the haptic sensor can measure rain accumulation very accurately (90-100% accuracy in Tempest and 80-100% accurate in SKY) compared to accumulation measured by a conventional rain gauge, which should also be well sited and co-located.
A conventional rain gauge can be highly precise but a haptic sensor is able to provide details on rain start time, event duration, relative intensity and rain rate at 1 minute resolution! Not to mention there is no need for the user to manually collect data after each rain event.
A calibration adjustment may be required if your haptic rain sensor is not producing accumulation measurements within accuracy specifications. You should first ensure that your mount and installation is sturdy as over-reporting of accumulation caused by unstable mounts and masts cannot be resolved through calibration.
If you think your device needs a calibration adjustment, we'd be happy to help! Our meteorological data science team can apply updated calibrations to your devices.
I have access to data from a co-located gauge I trust
We invite you to share the local day accumulation (from midnight to midnight) at your convenience...
- Please "register" your co-located gauge using this form: https://forms.gle/VZGKtFKwBQ7K8jaJ9
- Once registered, report individual rain events (ideally over a 24-hour period, from 12AM to 12AM) using this form: https://forms.gle/oakCdNrPgm4PZM4i9
- (Optional) Email email@example.com with any pertinent info about your device and installation, including photos, comments, etc.
We can use a limited amount of comparison data to determine a new calibration but of course, more data from a larger sample size of rain events is preferred.