After Friday’s big chill, we will start Saturday off on a very cold note with widespread sub-freezing temperatures. But a ridge of high pressure builds back in quickly, resulting in rising temperatures that will get us back into the mid-60s by Saturday afternoon, and then into the 70s by Sunday. Warming continues through mid-week with highs topping out near 80 degrees by Wednesday.

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The earth’s spinning is primarily responsible for why winds don’t just blow straight from high pressure centers into the lows. Called the Coriolis Effect, it is what causes winds to spin counter-clockwise around low pressure systems (in the northern hemisphere.) Some also refer to it as the “Coriolis Force”, as if there’s a mystical extra-terrestrial force acting on clouds and toilets worldwide, but in actuality, the forces are just gravity and inertia. It is a complicated subject to explain in so short a space as this, but I’ll give it my best shot.

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If you are above the North Pole looking down, the earth is spinning to the left from your perspective. If you roll a beach ball from the pole toward the equator, it will veer to the right from the perspective of one on the ground. This is what happens to air flow from high pressure to low pressure… it will veer to the right. So air curves to the right (clockwise) around high pressure centers, and consequently counter-clockwise around lows.

 

 

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