Hanna's Gift: Rain and Rainbows

With the talk of the week come and gone (by the way, I think the forecast and track worked out pretty well), we did get some good things out of the storm.
This Doppler estimated Rainfall shows:
Yellow- Over 1.5 inches
Red - Over 3 inches
Purple- Over 6 inches west side of DC. Tony Pann informed me about numerous water rescues.
More rain fell north and west
Less rain fell around the beltway and the eastern shore...
After a wet spring and summer, August was about 2 inches below normal on rainfall. the 1.64" at BWI made up for some of that and keeps us 3.29" above normal on the year.

BEAUTY How about the rainbows... I did say plural... there was a double rainbow that formed after 7pm and was visible in most spots. Technically everyone sees a different rainbow anyway, I did not want to geek out today. This was most likely the brightest, and best looking natural rainbow I have ever seen. Glad I can a camera handy. Enjoy the pictures (which do not do the full double arch justice). I also have a YouTube video below....

Rainbows

Living on a hill and afternoon showers has provided a vantage point for great rainbow spotting over the past few days.
This is what I captured yesterday afternoon. Indeed we had rain falling with the sun out, and this slow moving cell held the rainbow in the sky for nearly 30 minutes. A rarity!

I am glad I got this image, which turned out to be a much better overall experience then what I had on Friday.
I thought I would keep this story to myself, but it is so pathetic, I had to share...I was just relaxing on a day off, and doing some yard work/getting ready for dinner, when I spotted - uh- a rainbow. I realized that I had to get the camera, and did a light job into the house. I should add that I was barefoot, and it was wet. As soon as I made the turn from the driveway to the concrete garage- I bit it. With no traction, I wiped out and landed on the inside of my right knee. I stayed there for 30 second, just waiting. My wife, saw the whole thing and I think went back into the house quietly to hide her laughter. Here I was on an extended week, hoping to go out for an evening run, and play golf the next day, etc... When I realized nothing broke, I got up to get the camera and grab the photo. Scratch that, I hopped! Bruised and battered, I did have a pretty harsh contusion on my tibia, and sore lower quad muscle. "How would you explain this, if we had to go to the hospital", my wife asked. "Um, Doc, I was chasing a rainbow." Not my proudest moment, and now you all know. I did push myself out yesterday for that run, and came home to this. Not as exciting, but a better arc. It's got to bring good luck, right. I'm waiting for the bird droppings next.

Rainbow! A little science. A little change in fortune.

Thanks to Jim Schuyler, here are some great pics of a rainbow that developed yesterday at Towson University. This is the result of the proper conditions that are more likely late in the day. A shower passing east still dropping rain, but sun, low in the sky to the west. The sunlight breaks up in the falling drops like millions of prisms. The lower the sun angle- the better the chance of a second rainbow forming. One thing you will always see:
The colors are always in order with the red on the outside and the violet on the inside. This has to do with the wavelength of light with these colors. Remember ROY G BIV. The way we were taught Red, Orange, Yellow, Green, Blue, Indigo, and Violet. Well let's think outside the rainbow for a moment....
Infared is the wavelength just beyond the red. It is the part of sunlight (just outside of the visible range) that is responsible for heat. That is why heat lamps at cafeterias, or rest stop food joints are often red. It is also why you feel warm when the sun shines on you. This wavelength is somewhat long and doesn't penetrate the skin, but just at the surface results in molecules speeding up and producing heat.
Ultraviolet is just beyond the violet. Also something we can't see, UV is responsible for tanning and burning of our skin. It has a smaller wavelength that can penetrate the skin and cause our bodies to react with melanin... etc, etc, etc.
So all of the colors have their place, and since red has a longer wavelength, it does not refract or bend much. Violet has a much shorter wavelength, so it bends the most and ends up on the inside of the arch with the sharpest curve. The result: Red will always be on top, with Violet on the bottom.... for a primary rainbow.
Not all rainbows are the same...Jim was able to capture this rare double rainbow. The conditions have to be nearly perfect for this. While we can often see a rainbow based on sun angle usually after 4pm or so, a double rainbow usually occurs within the last hour of sunlight. A shorter window of opportunity. You also need to have a wide open view that is not blocked by trees, hills, or buildings.
The secondary rainbow is much fainter- almost hard to see, but will act like a reflection of the first. So the colors will be in reverse order- with red on the inside and violet on the outside. Now I am tempted to go get a box of lucky charms. If I could only find $2.50 gas at then end of these I would be happy.
Well we have the weather to bring us happiness now. One last disturbance will bring us clouds and some showers on the north side today- but then we turn the corner. The pattern will flip for the nation. Cooler weather out west, while we get a ridge of High Pressure to build back in. more sun and an eventual shift to a southerly wind still promises a sunny, dry weekend. Here are the Sunday maps from the GFS. The surface maps show High Pressure overhead, which means sinking air. That translates to sunshine, and light wind- which will shift to the southwest by Monday. The color map shows the 850mb temperatures. The yellow/orange shows temperatures at 5,000Ft around 15C. That will translate to surface temperatures back into the upper 70s. I see us back to the low 80s by Memorial Day.