(also see Clouds)
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(last worked on: August 12th, 2019)

* As threatened on my "Clouds" page, the "seeing" (as it's called) for doing astronomy here (near the Pacific coast) is so bad, I think about trading in my telescope for meteorological gear. (Actually: we've purchased two residential type "weather stations" and they've both broken down --the most recent one because its guts filled up with rain water --apparently due to the manufacturer having neglected to drill out molded-in housing dimples for drain holes.)

Of course, a proper weather station needs standardized, calibrated instruments, good siting and a good site wind profile, which allows its instruments to read out meaningful numbers. For example: while the home owner might be most interested in the wind velocity across his/her long suffering roofing, a creditable anemometer should be located 10 meters (about 33 feet) above the local, level terrain --and not in the "wind shadow" of buildings or trees in its vicinity.

* I won't attempt to present much of the science and art of meteorology here. This page is for stuff I just happen to know (maybe only think I know or suspect) --which might be of interest to others --like:

Wind Chill:

* "Wind chill", or the more scientific sounding "wind chill factor" --has been in the news lately (January, 2019, re: that deadly incursion of frigid polar air) --and has been a spuriously derived set of numbers. It's only since 2001 that the Canadian Meteorological Service attempted to relate wind chill to exposed skin (thanks to a dozen hapless volunteers in a frigid wind tunnel).

Modern wind chill citings do attempt to correct official wind velocity --but for a person standing in an open field, which probably says nothing about the wind where you're standing. Again: that official wind speed is taken 33 feet up at the local airport --and diminishes sharply with altitude and obstructions (which is why butterflies and moths navigate close to the ground). Neither does it address humidity or what you're wearing.

* Story #1: I once read that the idea and first development of a wind chill graph was thanks to photographer attached to an early Antarctic exploration team. Bad weather was keeping him pinned down in his miserable tent --so what to do? Why: turn his experience into a gainful project! He had one of those classic plastic (Bakelite, probably) film developing tanks with a hollow center stem, into which you insert a glass thermometer. He had some sort of an anemometer outside the tent, so he filled the tank with water (and people are 95% water), which was raised to that traditional 98.6 degrees of average body temperature. Then for fixed, short periods of time, he hung his tank outside his tent on a pole --not exposed to sun light, near the anemometer, and recorded how fast its temperature dropped --against wind velocity. (These days, 3 mph or less is considered "calm".)

* Story #2: A pair of scientists working in Antarctica (Paul Sipple and Charles Passel) placed bottles of warm water on the roof of their hut, coming up with kilo-calories of heat loss per exposed square meter of surface area at various temperatures and wind speeds --which was uselessly arcane for sensationalizing a popular weather report broadcast. However: 20 years later, a creative specialist (Charles J. Eagan) re-arranged that data to express wind chill in the now familiar terms of temperature and wind velocity --in order to prepare soldiers for winter service.

** None of the above is to at all minimize the danger of wind and frigid temperatures, for which citations of "wind chill" at least serve to make us mindful.

* I lived in Minnesota for the first half of my life --ARGHHH what a miserable existence in winter! White knuckle commutes to work, to the job site and essential shopping. We could look forward to ending our old age by falling on the ice and breaking a hip --or maybe having a heart attack whilst shoveling snow or raking it off the roof. Then there was the running of cold-rigid and tangled extension cords out to where your dead car was drifted in --or removing the car's battery with frozen fingers and carrying it indoors to warm it up. One had to dig out and move that car before the snow plows came or else a city wrecker would tow it off to an impound lot. Meanwhile, an ice dam over the eves was backing up snow melt, until it leaked in and down our interior walls. (Zig-zag heating wire on the roof over the eves might be left on all winter --to match the heat loss through the roof. Try not to get electricuted via the aluminum snow rake.) (That was before GFIs.)

* Just a little bit of knowledge about relative humidity, temperature versus altitude, droplet nucleation and such give us thinking "tools" as to what's going on with the weather.