We are about to go from a sunny and dry pattern to a cloudy…and dry pattern. The hopes for a wet weekend are diminishing as the offshore low pressure systems are trending too far to the north as they approach the coast. They will be close enough to drag some clouds across the region, but all the jet stream support and cold air will stay too far to the north to shake any moisture out of them. Temperatures will warm into the 50s throughout the weekend.Clouds

“I know Dec 20 or 21 is the shortest day of the year, but what is the date of the latest sunrise?”

One might think that the latest sunrise and the earliest sunset would be on the Winter Solstice (Dec 21 usually), but because of the eccentricity of the earth’s orbit that isn’t the case. The sunrises keep getting later for about two weeks after the solstice, and they max out about the 5th of January, just before 7:20 local time. The earliest sunset is on the other side of the solstice, on the 8th or 9th of December (depending on the year), at 4:36 local time. The combination of the two ends up making the solstice (around Dec 21) the shortest day of the year.

(Editors Note: A reader wrote in with the following: “So, I’m confused, after reading your RGJ newspaper column today; does it mean that after the winter solstice (Dec. 21 +/-), the days get longer in the evening or in the morning?  Please respond!  Thanks so much.” 

What it means is after the solstice the sunset get earlier (very slowly) and the sunset gets later (at a faster rate), so the net effect each day is a lengthening day. If you graph the sunrise and sunset times over the course of the year, it’s a parabolic curve, so the difference from one day to the next when the curves bottom out is very slight, but the rate of change increases as you get further from those dates.)

 

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