UV Index (sun strength) early AM versus evening

[Deisel Weisel]

I was looking at the weather forecast site, Metcheck, and noticed how the UV strength given for 6pm-9pm is always zero, no matter how clear the sky is. Yet 12 hours earlier, 6am-9am, if the sky is clear enough, there’s reasonable UV strength.


(UV is the 3rd column from the right. Cloud cover is the 7th column.)

I wondered if this was an inaccuracy by Metcheck, but I found this, which seems to back it up: http://en.wikipedia.org/wiki/Ultraviolet_index#med...

It’s NYC, not Essex, and Essex is what’s relevant to me, but it seems to confirm.

I suffer a heart abnormality, which I’m trying to do my best for, and on my list is vitamin-D. Apparently, oral supplementation of vit-D, doesn’t rate as highly as UV exposure, particularly when it comes to benefiting the heart. So looks like I’ll be switching my daily 6-7 mile walk from a 6pm start, to a 6.30am start.

Explains why I still look so pale and pasty, despite walking 45 miles a week, in the evening sun.

Edited by Deisel Weisel on Saturday 28th June 19:23

[Simpo Two]

At the ends of the day the sunlight is veing filtered by more atmospehere, which would explain some of it.

Go out at midday and lie in the sun, you'll soon go lobster! Better still, get on a boat and get extra UV off the water.

[Halmyre]

Early morning sun when I'm driving to work (6:30-ish) always seems brighter and more intense to me than at 6:30 in the evening. Possibly clearer skies - less water vapour?

[Simpo Two]

Or less dust/pollution?