Friday, January 16, 2009

Wild Temperature Swings

It has been really amazing to see the crazy temperature extremes this week.

Let's start in Alaska.

On Thursday, Jan. 15 they recorded a new record high of 44 degrees in Fairbanks. (ABOVE ZERO) It was not even a week ago (Jan. 11th) that it was 44 degrees below zero there! And 47 degrees below zero on Jan. 8th!

Three locations broke all-time record January highs, climbing as high as 54 degrees ABOVE zero, after spending 2 weeks between 40 and 60 below zero.

Much of central interior Alaska just experienced a 90 to 100 degree temperature swing in just a few days.

On Monday, Jan. 12 the low in the town of Central, Alaska was 52 degrees BELOW zero. Their high on Thursday, Jan. 15 was 45 degrees ABOVE zero. (that is a 97 degree swing)

The cause of the extreme warmth was a southerly flow of winds aloft that originated near Hawaii.

It isn't common for that type of warmth in central Alaska this time of year, but, it has happened before. Back in 1981 for instance.

Here in the lower 48 states, Bismarck, North Dakota set a new record low of 44 degrees BELOW zero on Thursday, Jan. 15.

So far today, they have hit 24 degrees ABOVE zero -- so that is a temperature swing of 68 degrees in 1 day.

Back to the tossing a hot cup of water into the cold air and watching it evaporate -- I was asked why boiling water and not just hot water from a tap?

I will be honest and tell you that in the course of my meteorology degree, I barely passed physics 1 and 2 -- not my strong suit. I was also working 2 jobs and doing an internship and honestly didn't put my heart and soul in it.

Having said that, I can only guess the boiling water temperature vs. the cold air is larger than the hot tap water temperature and the cold air.

So the greater temperature difference yields a more dramatic display of turning into water vapor.

Also, there will obviously be a temperature loss from the water in the glass as you walk from the tap in your kitchen and go get into launch position outside.

So boiling water poured from a tea kettle into the glass right before you launch it upward gives you the warmest water possible.

My OSNW3 friend from Wisconsin actually video taped himself doing this little experiment and you can watch it online. He posted a link in the comments section of my blog titled "Your Comments Are Great".

And someone noted how crunchy the snow is on his video. For those in snowy climates, you probably have noticed the colder it is outside the crunchier the snow.

(esp. seems to get crunchy once the air temperature nears or drops below zero)

Susan from SE Michigan said her husband left for work with clear blue skies Friday morning and when he approached the Detroit River downtown, about 10 miles from their home where skies were clear, it was foggy.

When the water is warmer than the air temperature it will let off steam essentially as the water cools down.

But in this case, the Detroit River is frozen! So I don't think that is the case here.

My guess is some kind of temperature inversion in the atmosphere, or possibly a factory sending off steam and it made a cloud bank of fog --- and perhaps a temperature inversion kept that cloud bank or fog trapped in and along the river valley.

There could be a number of theories. But whatever was causing it, I would suspect it had to do with the temperature profile of the atmosphere and the terrain of the river valley.

Here is an example of how river valleys can have a local impact on the weather.

In Colorado, we have the South Platte River that flows from the mountains southwest of Denver, northeastward up to the Platte River in Nebraska.

There is a town in northeast Colorado called Greeley that sits in the river valley.

When we see arctic air masses hit eastern Colorado, and everyone drops into the 10 to 20 below range, it may take 3 or 4 days to recover back to normal temperature readings for most locations, but it can take Greeley several days to even a few weeks!

So while we all climb back above zero and into the teens and 20s, they may struggle to reach zero degrees for days.


Cold air is heavy and sinks. And often in the winter, you have a temperature inversion where the air actually warms up above ground level.

So when we get a cold arctic air mass in here, the air sinks down into that river valley and gets trapped.

Until a good wind maker or some kind of weather system potent enough to stir the lower few thousand feet of the atmosphere comes along, that cold air just sits and sits until it slowly moderates with time.

A similar situation happens in the town of Gunnison, Colorado -- and in Alamosa, Colorado. Both places sit in a valley surrounded by 12,000-14,000 foot mountains. Almost like a bowl.

The cold air settles into these valleys and stays for days or weeks until a weather make comes along and scours out the cold air that is trapped in the valley.

And fanghopper in New York said they have heard of taking bubbles (like kids play with) and blow them up in the air when it is bitterly cold and they will freeze before hitting the ground.

Just do it over the grass so they don't land on pavement and make things more slippery than it already might be from ice and snow!

Have a great weekend!


  1. Just so you know, I tried this last night myself (originally I only read about it on the internet). I was unable to get any photos because the bubbles of course blow around quite unpredictably...and I couldn't quite convince my photographer friend to help me in the -15 weather...what kind of friend is he, anyway? ;)

    The soap bubbles freeze into a plastic-like consistency, and rather than popping with a burst and a splatter, they sort of collapse on themselves. They also get pretty frost formations on them as they freeze--the feathery pattern like you see on windows--that's if you can stay close enough to one to watch it, or capture on on your bubble-maker without popping it.

    Hours of entertainment!

  2. Chris,
    I wasn't going to comment on fog, but on space weather as the Cocorahs site mentioned. There is a great site for space weather and solar activity. I am one of those nerds who find this stuff exciting. It is a NASA site and if you Google and enter Heliospheric, you will be able to access the Heliospheric lab site. There is also info on comets and transits of planets. As far as fog is concerned, we are having bouts of ice fog. It is coating the streets and wires and causing auto accidents and power outages. It also produces ice crystals that appear to be snow flurries, but they are much lighter. If you can catch one, you can see the crystals. Cool stuff.

  3. Tossing a cup of boiling water into cold air and watching it "instantly" evaporate is an example of extreme vapor pressure and surface-to-volume. The greater the vapor pressure and surface area, the faster the evaporation. On the air side, vapor pressure is increased when the air is as dry as possible-- in this case extreme cold. On the water side, vapor pressure is increased by raising it's temperature as high as possible-- in this case to boiling. And then a big wide toss spreading out the water in a big thin sheet completes the recipie, and bang! Instavapor!

    On a similar note, there's an old wives tale that boiling water will freeze faster than cold water. It won't-- as long it's the same amount of water with the same exposure to the cold.

    But if a large tray of boiling water is left out on a cold dry day, then a lot of that water will evaporate quickly. And what's left will freeze faster simply because there's less water left to freeze. It takes a lot of energy to freeze water, and a simple way to freeze faster is start with less water!