Friday, January 8, 2010

January 6-7 storm

The beginning of the new year has started a new trend in our weather.  Cold and snowy.  We are currently in the middle of one of the coldest cold snaps (close to the top 10 for Columbia), and from the period of January 1 - 8, our mean temperature is a mere 9.8°.

A low pressure system plunged SE on Wednesday, January 6.  In the morning, the system was centered in South Dakota, and by 2:50 p.m., we started to see our first flakes fly.  The line of snow had to push through the area by about 50 miles before the snow could saturate the lower layer of the atmosphere and reach the ground.  With the sub-freezing temperatures we experienced prior to this (we hadn't seen above-freezing temps since 12/31), the snow stuck quickly and the roads got slick in a hurry.  Of course, folks in Missouri really freak out when snow hits the roads.  Many people don't realize that you can't drive the same in all conditions.

The snow continued at a moderate rate throughout the night.  I went to bed around 10:30 p.m. (late for me) before the winds picked up.  We had right at 2.0" of light, fluffy snow.  The flakes were beautiful, perfect dendritic works of art.  The true work of a master craftsman.

By morning, the scene had changed quite a bit.  After the strong low pressure system pushed through, the backside brought strong NW winds gusting around 30 mph.  I have picures to share with you, and will add them to this post early next week.  The houses in the neighborhood created wind tunnels and provided some wonderful drifts between and around them.  This made measurement a nightmare!

How in the world do you measure such a snow??

I went around, taking multiple measurements...some were 1/2", some over 12".  I finally decided to let math do the work for me.  Using the data from the KCOU station at the Columbia Regional Airport, I calculated the snow density, and using my melted snow from this station, I figured up a number of 5.4".  This turned out to be close to the average of all my measurements, so that's the figure I went with.  Not as quantitative as I wish, but it's the best I could do!  If any old hats have any suggestions for measuring blowing snow, I'd be happy to learn more.  Our snow density was 20 : 1

Frigid Temperatures

Here's a rundown of this month's temperatures so far:

1/1:  20  10
1/2:  18   0
1/3:  15   2
1/4:  16  -3
1/5:  21  -2
1/6:  24   3
1/7:  19   1
1/8:  10   2 

It has snowed 5 of the past 8 days.  It's turning out to be a beautiful winter.  Look for updates including pictures early next week. 


OSNW3 said...

Looking forward to the photos, WxWatcher. Blowing snow is always difficult to measure. There are many ways to do it and each situation is different. If it's the best you can do, it's good enough! :)

My monthly mean is a good 5 degrees warmer than yours. Quite the anomaly, isn't it?! Regardless, I am happy with January and I am glad you are too.

Also, you are very welcome for the loop. It's my pleasure as I enjoy putting the loops together. I am glad it will get good use and I hope it proves productive for your classroom.

Chris said...

Also looking forward to the pics.

Blowing snow is awfully tough. I haven't really found a way to measure it quite accurately. :/

P.S. I'll be ordering my new station in the next couple days! Should be exciting.....

WxWatcher said...

OSNW3, it's interesting about the cold weather. This morning, it was 7° with no wind as we left for church, and I was out the door without a coat! Felt pretty good actually. Now it is a balmy 13° with full sunshine. It sure doesn't take long to get used to the cold.

Chris, congrats on the new station! What did you end up getting?

I know I speak for many when I say I look forward to reading your data.

WxWatcher said...

OSNW3, here's a great graphic showing the impact areas of the cold weather.

Chris said...

I researched much, and I ended up with the Davis Vantage Vue. They have a good deal for it on Ambient Weather ($299).

Now the only problem is the mounting. Where do you mount your stations?

OSNW3 said...

"Measuring new snow accumulation is easy when the snow falls without wind and isn't melting on the ground. But when the wind blows, measuring snow becomes a real challenge. We deal with drifted snow by simply taking many measurements from a variety of locations and averaging them to get a representative measure. You will get the hang of this -- with experience."

Thanks for sharing that graphic. I am gonna link it in my latest blog.

WxWatcher said...

Chris, I live in a subdivision, so my station is situated in my back yard, as far from any houses as possible. I still get some interference with wind, making my wind speeds a bit lower than they should. (I don't think my wife would like the idea of the station protruding above our house...or the homeowner's association for that matter)

At school, I have the anemometer 5' above one of our outbuildings. It's a metal building, so I just mounted it directly into the side.

If your temperature sensor is remote, I'd find a shady place for it (unless it comes with a quality radiation shield), otherwise your temps will soar on a sunny day.

OSNW3, thanks for the link. Also, that's a cute pic of your little girl on your new post. Reminds me of our 1 year old. She loves to lay down in the snow.