A building ridge of high pressure peaks on Friday will result in sunny skies and a likely high temperature record of 80 degrees, easily beating the old record of 75 degrees seen twice before. Saturday temperatures will drop a bit but could still approach record levels before a weak storm system passes to our north late Saturday bringing a few clouds but very little chance of any precipitation. Temperatures remain in the 70s into the first of next week.

equatorial

Yesterday, Mike Walker wondered how they calculate the exact moment spring (or any of the other seasons) begins. It comes from knowing exactly where the earth is with respect to its orbit around the sun. Fortunately, astronomers can calculate and measure the earth’s position in its orbit very precisely. The moment of the equinox (when spring officially starts astronomically) is when the plane of the earth’s equator (extended outward out from the earth) passes through the center of the sun. At that moment, the sun’s rays hit the northern and southern hemisphere equally, instead of favoring one or the other. It’s not a time that is calculated based on any weather criteria, but rather astronomical criteria.

 

Advertisements