https://www.temis.nl/uvradiation/nrt/uvindex.php?lon=-75.5639&lat=41.4911This tool returns the forecasts . . .
at local solar noon of today . . .
for clear-sky conditions and in the absence of snow.
This is a UV forecast showing the
theoretical "maximum" amount
It calculates the UV value without clouds , air-polution and all other items which inhibit the UV radiation to reach ground-level.
Nothing wrong with the Temis values theoretical values.
Forecast-scripts use these values to combine UV with all other items into a more "real-life" UV-forecast.
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https://k3csg.altervista.org/index.phpYour page probably has a small script error as it shows the real-life UV value
as measured by your weather-station as"no radiation present" and the text "extreme" is not the correct text for that value.
Your station should have a functioning UV-sensor to use this part of the dashboard.
Check the Meteobridge upload file to see what values are uploaded. A "--" value could be the cause of the word "extreem"
Wim