I am looking for a meteorological measure (formula) of something which combines 2 or more of the following:
temperature, humidity, cloud, wind, precipitation, UV
I have searched, and for example, found the heat-index which combines temperature and humidity, but unfortunately the heat index only has a meaning when the temperature is high, I would be needing a measure which would always "make sense".
(Background information: I want to set up a mathematical model where some climate information is also included as a side measure and therefore want to "merge" the available time series to a new measure and have more information as input, since otherwise I could always only include a single information.
Further background information: Would like to measure the effect of those variables (single variables, or better yet, combination of some of those) on the time-varying infection rates of COVID infections, the reason those were chosen is because in papers surrounding the topic "meterological factors" and "Covid infections" those were chosen most often)