Cecil,
Wow! You went to great lengths on this one.
One thing that came to mind when looking at your rainfall criteria. Did you know that depending on the humidity level of the air that rain drops pass through the rain drops may never make it to the ground? So my point is, maybe it is raining and you just don’t know it.
Thanks
Paul
Rain that evaporates before it falls on your head is not rain by any definition that would be useful in the context of weather prediction.
I think you are referring to virga.
We did not use it to track humidity, for the reason that a historical review of the use of the storm glass showed it was unanimously touted as primarily a tool to predict, well, storms, for among other things attempting to prevent shipping and naval ship losses. See for example the testimony of Vice-Admiral Sir Robert Calder, who specifically credits storm glasses with allowing them to predict when a fierce storm was going to end, allowing the rescue of the Goliath. Fitzroy specifically recommended that the storm glass be put onto every ship in the British Navy to try to predict damaging storms - a condition of typically very high humidity at pretty much most times in temperate or tropical waters.
In addition to this issue, humidity varied at our house quite a bit over a single day - I checked two random clear days in a series of clear days as an example back in September, and found that the relative humidity varied from about 30% to 85% over a 24-hour period. Therefore, we felt that trying to predict changes in humidity would have resulted in a tremendous amount of noise which would not yield useful information.
Although Cecil did mention it, I must stress that reading storm glass crystals is an incredibly subjective thing. I referred to them as a “weather Ouija board.” Even if storm glasses actually had something going for them, somehow, user error would have to be high. I’m glad we made them instead of buying one for $179 (although the cost to make the first 6 glasses was about $50 a glass).
What I want to know is, in Slug’s accompanying picture, who’s Una and who’s Fierra?
Since I was the one who did most of the checking, I’m probably the one out in the rain.
(and it’s neat to have a Slug illustration of oneself!)