Is it currently possible to extract data from a cell in WolframAlpha in Mathematica Online?
WolframAlpha functionality is still under active development for Mathematica Online. Currently there isn’t a way to extract data from the WolframAlphaHTML function. We’re also working on support for free-form input. When finished it will be much easier to mix data from Wolfram|Alpha and Mathematica Online.
In Wolfram Cloud you can do with W|A things like:
WolframAlpha["sun spots", {{"SunspotsPartialTimeSeries:SpaceWeatherData", 1}, "ComputableData"}]
and more recent functionality similar to:
GeoGraphics[
GeoMarker[
Entity["City", {"London", "GreaterLondon", "UnitedKingdom"}]],
GeoRange -> Quantity[200, "Kilometers"]]