Centaurus – “… how come weather radar is often unable to pick anvils and CB tops.”
My description could have included ice particles and ‘mixed phase’ water/water-ice crystals with the water vapor.
Weather radars only see a restricted range of water particle size, and generally do not see ice crystals or small droplets e.g. WXR does not paint cloud or fog, only larger water droplets, e.g. rain.
I am more familiar with the older radars which covered a reasonable range of conditions; I suspect that the newer radars might require greater interpretation in non standard conditions. I recall that the large Cb anvils that I ‘experienced’ painted yellow/green. Hereby is a problem, in that some crew’s consider these conditions acceptable for hazard-free flight. This is not the case for Cbs; the yellow/green areas contain water / ice particles or vapor (small particles), which could lead to various forms of icing (and may involve turbulence).
Re “… while European CB's do have considerable moisture in tops and anvils (?) which are generally at much lower altitudes than their Pacific counterparts.”
I wonder if this has more to do with droplet size. Does WXR paint the European CBs more readily due to larger droplets, whereas tropical CBs, in colder air consist more of ice crystals? In my experience of both Cb types, engine icing problems occurred at the tropopause, and / or just below zero OAT, and particularly just over the top of a developing storm.