Precipitation Rate definition

[Paul Reed]

I'm using the UK Met Office API which provides weather forecast data in hourly intervals for the following 48hrs, it contains object data for precipitationRate and also totalPrecipAmount

The meta data describes precipitationRate as;

description: "Precipitation Rate"

unit: object label: "millimetres per hour"

and totalPrecipAmount as;

description: "Total Precipitation Amount Over Previous Hour"

unit: object label: "millimetres"

Does anyone know what the full definition is of 'Precipitation Rate'?

Is it;

• The average precipitation rate during the previous hour
• The peak  precipitation rate at any time during the previous hour
• Is it something completely different