Whats the Difference Between Mostly Sunny and Partly Cloudy?
'My' forecast, now, for tomorrow, Calvert County, is 'partly cloudy' from 1 - 10 p.m. (AFTER 'scattered t'storms' @ noon!)
'Whats the difference between mostly sunny and partly cloudy (or for that matter, mostly cloudy and partly sunny) in weather forecasts? Are any of those even specifically defined terms?
The short answer: about 1 to 4 oktas. Whats an okta? Thats a unit of measurement that meteorologists use when theyre forecasting cloud conditions, equal to 1/8 of the sky (though sometimes 1/10 is used). When the forecast is delivered, the number of oktas covered by opaque clouds (meaning that you cant see through them, and the sun/moon/stars/sky are hidden) is described using mostly sunny, partly cloudy and other terms were used to hearing. Each of these is defined by the National Oceanic and Atmospheric Administration and the National Weather Service in terms of oktas of cloud cover. The NWS Operations Manual breaks it down like this:'>>>
http://mentalfloss.com/article/56820/whats-difference-between-mostly-sunny-and-partly-cloudy