We have another weak storm system moving onto the west coast which could bring a few showers of rain and/or snow late Wednesday into Thursday. Any valley accumulations of snow will be minimal, and there’s only a slight chance it will make it over the mountains into the valleys. Temperatures will warm to the upper 40s on Wednesday before dropping to the low 40s and upper 30s on Thursday. Things clear out Friday and Saturday with only a few clouds remaining, and temperatures will be very chilly through Saturday, possibly dropping into the teens on Saturday morning.

Yesterday I mentioned that a one inch square column of air through the atmosphere would weight about 14.7 pounds. Here’s a question for you: If you cut that column in half, how much would the bottom half weigh? About 7.35 pounds, right? Nope. It would be somewhere around 14.5 pounds. The actual answer depends in part on how you define the top of the atmosphere (for our purposes, we’ll ignore the thermosphere), but most is packed in the bottom. Because air compresses, most of the atmosphere (from a mass standpoint) is crammed into the lower 5%.  More tomorrow.