The ridge of high pressure will continue to build into the Great Basin into the weekend, pushing high temperatures into the mid-90s on Friday and the upper 90s on Saturday. The ridge is flat enough to give us a stabilizing westerly flow across the west coast, so it is doubtful we will see any significant cloud buildup, much less any chance of thunderstorms.

Perseids

Yesterday I mentioned that the viewing of the Perseid Meteor Shower gets better after midnight. Because the earth is moving through the “debris trail” from a comet’s orbit, half of the earth is on the leading edge of its movement through space around the sun. Because the earth is spinning, the half of the earth “in front” keeps changing. Our time is determined by the position of the sun relative to our rotation. Here’s where it gets hard to describe, but in for a penny, in for a pound. At midnight standard time (1 am DST), we move from the “back” of the earth to the “front” in its travel around the sun. Just like a car moving through a snowstorm gets more snowflakes hitting its front windshield than its rear, more dust hits our side of the earth after 1 am summer time, creating more shooting stars.

meteor explainer

So stay up late and enjoy the show. You can always sleep in the next day.

 

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