4. Weather. From when I read TAF's and METAR's, I can't find any references to the tops of the cloud bases, only the ceilings. Where do people get this info?
'Tops of the cloud bases' and 'ceiling' means the same thing. I.e. the base of the cloud, which is the accurate one and what is published in TAFs and METARs!
Cloudtops on the other hand, are one of the most difficult things in meteorology to predict, and there are really only two 'accurate' methods of knowing this information -
1) Aircraft observation
and
2) Skew-T diagrams (if you're not familiar, I'd suggest reading up on them, they can be very useful if you have more than just a passing interest in Meteorology).
I may have missed something, so anybody please feel free to add to this!