The system now supports microseconds in all related time and/or timestamp fields. Microsecond support is opt-in, by default the requests and responses still use milliseconds. Examples in documentation ...

Partly cloudy. Slight chance of a shower. The chance of a thunderstorm. Winds north to northwesterly 15 to 20 km/h becoming light in the late evening. Sun protection recommended from 9:30 am to 5:40 ...