5:23 AM Wed, Oct 11, 2006 | Permalink
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It's true - our coldest temperature of the day is just AFTER sunrise. Laura from Southwest Portland sent me this email last week:
You mentioned something on this morning's newscast that reminded me of a question I've had for some time. It was about 6:20 and you said something along the lines of "we're about to hit the coolest temperature of the day"--as though we had not yet hit it.
Here's my question--it has often seemed to me that the temperature dips just as the sun is coming up--it's colder after it starts to get light than beforehand. This seems counterintuitive--what is happening meteorologically that would cause the temps to dip? Does the rising of the sun create some sort of wind or something?
Laura, this is an excellent question. And here's the deal...
If we've got clear skies, then all night long, the heat from yesterday is escaping to outter space and temperatures keep cooling. It seems like that would change as soon as the sun comes up.
But when the sun comes up, it's so low on the horizon its rays are too weak and spread out to have an impact. So we keep cooling.
This time of year, it's about an hour after sunrise when the sun is high enough in the sky that its rays hit us more directly. And that makes them strong enough to finally start warming us up.
There you have it...
Bruce
Bruce,
Fine you say this, and I believe it, but it doesn't seem that this is really much of an explanation.
I've been outdoors many times during very COLD temperatures in fields and the conditions have been "clear and cold" (but dry).
Then, once the sun came up and the rays were actually shining right ON me one would think its warming rays would start warming things up.
However in contrast the temperature would take a big drop and my toes and extremities would suddenly feel very chilled.
I look down and notice that now I have ICE crystals had formed on my boots and on all the wheat stubble in the field!
My question is where did all this extra moisture come from?
Not only did it get colder, but moisture arrived (where everything had been previously dry) and then it had frozen into frost.
I am an avid hunter and have sat out at both sunrise and sunset. I am wondering if this also happens in the evening because it does seem to me that just after the sun goes down completely it warms up again a little, in contrast to how cold it feels as it is going down
I have heard that this will be a big snow year for the porland area.With two to three snow events.What has been the discussion for the winter.
Bruce...
Last night in your weather news... when you mentioned the streaks in the sky I was so excited and hoped you would tell the public the truth about them... instead you told the public what you want them to believe. Those streaks in the sky are "chemtrails" ie. chemicals being sprayed on the public w/o their permission and being sprayed on the land/crops/water/animals, etc. This is an environmental and health matter of great importance. Please tell the public the truth as the public needs to be made aware that they are being used for chemical experiments, or worse, by our government. Check this fact out on the internet... you will find lots of discussion on it. Thank you.