Not sure if I am right about this .. but.Looks like the weather symbols, way wx is superimposed on en route window etc, all come from TAFs & METARs.
The care needed re this is well illustrated by situation today. Was thinking of going to the Lakes & perhaps return to Yorkshire via Carlisle.
Looks all OK on SkyDemon. BUT there is actually (09:24) no TAF for Carlisle. If I switch to METAR, then yes it shows freezing fog at ground level.
If I switch to PocketFMS that, as mentioned previously, uses a specialist aviation met forecasting from Switzerland, then it shows a predicted 500 ft cloudbase almost all day in the North Lakes.
In the end both cd be wrong!! But due to the variability of TAF publication, relying on this for wide cover is a bit risky in my view. The other source is continually updating and gives full geographic cover all the time.
I know Tim is working on improved wx data sources but meantime, take care. Perhaps the ABSENCE of an en route TAF cd be flagged up??
D