Crossing the Blue Line

My father used to work as a TV anchor at a small network in Vermont right after college. I am sure he was good at reporting on news and local events, but one day the weathercaster called in sick and he was forced to do the stations weather segment. Without thinking too far in advance, he got up and was standing in front of a green screen pointing at various atmospheric features of which he had no knowledge about. Pointing out a specific item, he very solemnly told everyone in Burlington, VT to watch out for this approaching blue “spiky” line from the west. And moved on. Presumably Vermont survived the great attack of the spiky blue line, but what was he actually talking about that day?


Bane of Vermont, circa 1983.

On weather charts, blue lines with protruding triangles are denoting something called a cold front. Cold fronts are a very familiar atmospheric phenomenon and can sometimes result in extremely dramatic looking skies. Put simply, a cold front is simply a large mass of relatively colder air invading space occupied by relatively warmer air. Generally, they act like a snow plow to the air already in place by pushing it all upwards higher into the sky. It is this lifting action that creates the clouds and rain that weathercasters forecast for a frontal passage event.


Fronts in your mirror may be colder than they appear.

So what exactly happens when a cold front passes? Well, the obvious answer is that the temperature drops, since by its name, coldness is implied. Some other, more subtle things do occur though. Due to the genesis of a cold front, it sits in an area of low pressure. So as a front approaches, the atmospheric pressure around one will fall. This is because a cold front actually cannot move on its own. Rather, it must be attached to a low pressure system (those giant, red Ls that one might find on a weather chart) which in the northern hemisphere rotates all the air counter clockwise. This rotation of the air (wind) moves the cold air. As all the warm air gets lifted above (this is called Isentropic Lift, remember that; it might be a trivia question at your local bar next week) it cools rapidly which produces all of the moisture such as clouds and rain which can help make a cold front visible to the naked eye. Another telltale sign that a cold front has passed is the change in wind direction. As everything flows counter clockwise around a low pressure system, the cold front must too. The direction of movement will lend a change in wind direction to wind coming from the west-northwest. After the front has passed, certain things start to undo themselves. Mainly, the pressure will begin to rise as the low pressure system skirts away. Markedly colder temperatures will now inhabit the area and everyone might be slightly damper.


Cold air meet warm air. Warm air, prepare to get high(er).

There is a ton of science going on here that certain people have devoted their lives to studying that simply can’t be fully discussed in a mere blog post, but at least now anyone who read this is slightly better equipped to discuss that feature that my family name nearly incited as a horseman of the apocalypse.

Brendan Farmer

What’s the Wind Chill?!?!

Well everybody it is time once again to “snowsuit up” and prepare for the some of the coldest weather mother nature has to offer. 2 weeks ago i spoke about the main thing people fear during the winter, blizzards. However one of the main daily factors people care about during the winters here in the Upper Midwest, the Wind Chill. Everyone knows that the “Wind chill Factor” makes the temperature outside feel even colder, but what are the true dangers and science behind this seemingly mundane fact. Below is the National Weather Service’s Wind Chill Index and calculator.

http://www.nws.noaa.gov/os/windchill/index.shtml

Wind Chill is dangerous because the effect of the wind blowing over the skin pulls moisture out of your skin, causing the skin to dry and crack. This in turn causes the skin to lose heat much faster because the moisture in the skin helps hold in some heat. After prolonged exposure the exposed skin can develop what we know as frostbite. Frostbite, is of course very dangerous because it can cause a permanent loss of feeling in the affected flesh. For more information I have linked a description to the Mayo Clinic’s page below:

http://www.mayoclinic.org/diseases-conditions/frostbite/basics/definition/con-20034608

The dangers of Wind Chill during the winter are very real, and during the days when people are most vulnerable to extreme frostbite, the National Weather Service will issue a “Wind Chill Advisory” to warn people of the dangers of leaving skin exposed outdoors. So remember everyone, when the weather is cold, and the winds are strong, get out those winter snowsuits and stay warm.

~ Sam Umhoefer

Bombogenesis Season

It is bombogenesis season, which means we have to be on the lookout for one of the most exciting weather events known. What is a bombogenesis? A bombogenesis is when a mid-latitude cyclone drops in surface barometric pressure by 24 or more millibars in a 24-hour period. The height contours pack around the center of the low, and brings strong winds and precipitation, and potential blizzard conditions during the winter.

Surface Pressure Map

The most common time of the year for them to occur is in the cool season between October and March, when temperature gradients are large between high and mid-latitudes. They occur with cold air masses meeting warmer air masses, with strong divergence aloft, and a strong jet streak diving aloft.

4 years ago this month, the people in the upper Midwest got to experience such an event (Both images from said event). It brought a new record low pressure to the state of Minnesota of 955.2 mb (which is equivalent to about what a category 3 hurricane would produce), and 40+ MPH winds throughout the upper portion of the state and even some strong snow totals up around 7 inches. I just remember it being constantly rainy with strong winds for about 2 days here in Grand Forks, and it was miserable but exciting. There was also recently a case in January over the Northeast, which was known as winter storm Janus, which brought about snow totals of over a foot of snow in a single day over most of the northeast.

Map

But it is that time of the year for these storms, and everyone should be on the lookout as these weather bombs can bring exciting but possible harmful weather into the region.

- Tyler Reis

Meteorology: Just Another Retail Business

How can meteorology be similar to a retail business? It starts with the models. The models would be the companies that produce products that are sold in stores. Models have little interaction with the customers. They do however produce a product that
everyone wants. That product is a weather forecast.

The people that try to sell the product are broadcast meteorologists. They acquire these models and act as sales and cashiers trying to sell the product. Most of the time, people are satisfied with this product. However, there are cases where the product is faulty. Then, these broadcast meteorologists become that person at the returns desk that has to explain why the product is faulty. With experience in retail, I have worked the
service desk. Customers have come in looking for an explanation and let me tell you, these people are not nice about it. They come in blowing steam and think they rule the retail business. The same thing happens with broadcasts meteorologists. Even though
the product cannot be returned, the public has an earful to say. Sometimes it is so bad, that their email and voice mail are filled to capacity with messages. Even worse is when the public think we have control over the weather. They expect us to fix it when it doesn’t cooperate. If the public isn’t happy, then most likely the station manager feels the same way.

Now what happens if the customer doesn’t want to talk to the cashier? Instead, they would rather talk to a manager. The manager of this retail business is the National Weather Service. Every broadcaster that doesn’t work for the NWS looks up to them for
leadership. The NWS usually gets the most complaints, because of the responsibilities that they have. They must sell the product for the right condition. If they sell the wrong
product (clear skies) for the wrong situation (severe storms), then there will be many complaints. It’s like buying a dish sponge to clean your car. It just doesn’t make sense.

So hopefully you can see what I am getting at. Meteorology is just a retail business. The models are the companies that produce the products; forecasts. Then broadcast
meteorologists are the sales and cashiers of this retail business. The NWS are the managers that oversee the business. I never thought that I would work in retail ever again, but truth be told, I will be working in it for the rest of my life.

-Ben L

Weather Challenge

Something I was always taught was, “If you think they you can do something better than somebody else, prove it.” Whether it is drawing or it is forecasting the weather it can always be a fun experience. For somebody who is interested in meteorology one of the great things they can do is to make their own forecasts and see how it compares to not only their local weather man but also compare their forecast to that of the National Weather Service. A lot of websites give one access to the same models and data that is available to the NWS employees, and even if you’re not sure what a derecho is, there are great ways to learn about what it is that makes up weather prediction. Better yet if one would like to learn more interesting phenomena one could take a look at the National Oceanic and Atmospheric Administration’s glossary of weather terms.

http://w1.weather.gov/glossary/

NOAA weather Glossary

Once you’ve gotten a handle on forecasting a fun activity that you can participate in is the weather challenge. It’s aimed at college level students, Professors, and NWS employees and you just need to get into contact with a local manager. IF you have problems finding out who your local manager is you can always email your information to the weather challenge manager. What makes the weather challenge fun is that every two weeks forecast location rotates to a new area of the country. Having a city by the coast may be easier for some people to forecast, then in two weeks it will change to somewhere located in the mountains. Easier to determine things like temperature are balanced by harder things like precipitation. Plus there is a scoring system in place so even if your wind speeds are a little high, but your temperatures are spot on you still can have a decent score. You may ask yourself is there a prize? Well of course! The top competitor in each class wins a trophy, but more importantly one gets invaluable experience in the real world versus a classroom where things are just theoretical!

http://wxchallenge.com/index.php

Weather Challenge Homepage

Radar..Did you know?

Radar..Did you know?

Image Source: www.wunderground.com

In this day and age, most everyone is pretty well acquainted with radar. You see it on the news, on your computer, and on your phone. Weathercasters use it to track storms and locate snow bands. The National Weather Service uses it to locate possible tornadoes. But did you know that radar can pick up many different things besides weather? And did you know that meteorologists are not the only ones that use it? Note: If you want to learn how radar works, check out this great post from Tyler a few weeks back! http://cloudburst.areavoices.com/2014/09/18/an-introduction-to-radars/

A Brief History:

Radar, or RAdio Detection And Ranging, got its operational beginnings during World War II. Initially used to detect enemy aircraft, military personnel soon discovered that radar had a knack for detecting precipitation as well. While an annoyance at the time, this proved to be a huge discovery for the field of forecasting weather, and radar has been an important tool for meteorologists every since.

Birds, Smoke, and Planes, Oh My! :

Radar is able to see much more than just precipitation. As mentioned above, certain types of radar can be used to detect aircraft, making it very important for military applications. But aside from aircraft, did you know that radar can detect living objects such as birds, bats, and insects? Like precipitation, these living objects will reflect energy from the radar beam back at the radar, making them visible. The result? Cool radar images like these “roost rings” (expanding rings caused by birds leaving their roost) below:

And this cool image of mayflies leaving the Mississippi River on the WI-MN border! (Gross!):

And beyond living targets, radar can also detect smoke plumes from forest fires, dust storms, interference from the sun, wind farms, and gust fronts! Imagine that!

Smoke Plumes & Wind Farms:

Dust Storm In Texas Panhandle:

Sunset Spike:

Gust Front:

Image Sources: NOAA

If you keep a close eye on the radar, you might just see some of these phenomena, and hopefully now you’ll be able to impress all your friends by telling them exactly what’s going on!

-Logan Lee

Radiative What?

As you’re eating dinner, the 6:00 newscast blares on your television. Suddenly, you are shushed. “The weather is on!”. While you patiently listen to the Meteorologist’s forecast, you hear “Overnight temperatures will stay in the lower forties. The clouds over us will keep us warmer tonight.’” Why will those clouds keep us warmer, you ask?
It all starts with the radiation budget of the Earth. Overnight, there is a net heat loss caused from heat escaping from the Earth’s surface. This heat is infrared radiation from inside the Earth. During the day, there is a net heat gain from ultra violet radiation from the sun. This balances out over the entire Earth according to the Law of Conservation of Energy.

This image is a view of the entire radiation budget of the Earth. I only mentioned a few processes, but there are many more to explore.


During overnight hours, cloud cover can vary. If a layer of clouds covers the sky it can act as an insulator. A TV Meteorologist may often refer to it as a “blanket”. This figurative “blanket” can trap the infrared radiation escaping from the Earth’s surface, and lower the net heat loss in the lower atmosphere. If less heat is lost to the upper atmosphere, we stay relatively warmer in the overnight hours! However if skies are clear, the infrared radiation escaping from the surface flows up and away from the surface to an upper boundary much higher than a cloud deck would be.
Although nighttime clouds do not allow us to see the stars, they can provide us a little more warmth at night.

-Brianna Kump

Hockey Season Once Again

Well folks, it is that time of year again. Winter? Nope. Halloween? Nope. It is Hockey Season. The NHL Season starts tomorrow and I couldn’t be more excited! 82 regular season games per team; 1,230 games scheduled in total, who wouldn’t be excited!

Ralph Engelstad Arena


Hockey is played on a giant slab of frozen water that remains frozen by a refrigeration contraption that costs a lot of money. The game is also played indoors where fans remain nice and warm while watching their favorite teams. What happened to the old days of Hockey? Outdoor hockey. Pond hockey.
The NHL had five outdoor games last year; four in the “Stadium Series” and the popular “Winter Classic”. These outdoor games were played all over the country, ranging from LA, California to New York.

January 25th, 2014, Dodger Stadium: The high temperature for the day topped out at 80 degrees, well above the inside temperature of any hockey arena.
January 26th and 29th, Yankee Stadium: Temperatures were in the lower 30s to lower 20s for highs with lows in the mid to upper teens. Traces of snow were recored.
March 1st, Chicago: High temperature reached 31 degrees with a low temperature bottoming out at 11 degrees. 3.7 inches of snow fell throughout the day making for a slow paced game between the Blackhawks and the Penguins.
The Winter Classic was played on New Years Day in Ann Arbor, Michigan. The high temperature reached a balmy 17 degrees with a low of 11 degrees. 6.4 inches of snow fell throughout the day. Not ideal conditions for playing hockey but classic “Old Time Hockey Conditions”.

photo credit: ESPN


There are currently only two outdoor games scheduled this year in the NHL. It will be interesting to see what kind of impact the weather will have on attendance, travel, and game play this year. The weather often does not have a huge impact on professional sports due to the fact that most are played indoors. However, the weather can make it dangerous to travel in route to and from these games. It is never too early to think about safety while driving on snow covered and icy roads.
Be safe and Go Wild!

-Joe Heiden

Motorsport and Weather

If there is one thing that the rest of the world seems to thoroughly enjoy but escapes most of us here in the United States, it would probably be the sport of Formula 1. While North America actually offers two tracks every year for the racers to gather on, one of Montreal and one in Texas, the events are on in such odd hours usually that most people do not get the chance to watch. That being said, behind baseball and my Red Sox, Formula 1 is probably my favorite sporting event to watch. This weekend was the Japanese Grand Prix, held in the Kansai region in the city of Suzuka. Timing this year also worked out to coincide the race with a very large and strong typhoon whose track was set on track location.

A typhoon is an extremely low pressure feature that forms in tropical regions as a result of high temperatures and humidity. The fact that areas near the equators can feature light winds, results in easy forming convection. That is to say, air becomes extremely buoyant and rises. This could be easily demonstrated by inflating a balloon and taking it into a swimming pool. Swim down the bottom of the pool with the balloon and let it go; because the air in the balloon is far less dense that the water surrounding it, it will rise quite rapidly to the surface. Essentially, that is what the atmosphere does with warmer than normal air – because warm air is less dense then cold air, it rises. It is also this warm air that causes the low pressure feature. Imagine two cups sitting on a scale. One is empty, one is filled with water. The one filled with water will weigh more and thusly exert more pressure. The empty one will conversely exert less pressure because it is overall less dense due to the fact that air is less than water. The empty cup is analogous to a low pressure system. Think of a low pressure as a well, it is deep and wants to be filled. Cold air in this cause fills the well because it is more dense – that is to say on a more general scale cold air is attracted towards warm air because warm air is less dense. When all this is combined, that is how very strong typhoons fill. The pressure on the surface decreases because of warm air and cold air thusly attracted to this. The cold air is then heated and joins the warm air party. Without wind, this process just keeps on going until a typhoon is formed.


Typhoon, meet Japan. Japan, meet typhoon.

Off the coast of Japan, the typhoon that brought rain the Japanese 2014 Grand Prix can be seen. It spent time strengthening over the warm waters of the pacific and started producing gusts in excess of 150 miles per hour. It proceeded to move north and produced a sizeable amount of rain and winds on Sunday. As F1 cars are effectively airplanes flying upside-down, they displace any moisture on the track upwards. This creates visibility problems, which combined with trying to drive at 100 miles per hour around tight corners, creates a spine-chilling spectacle for viewers.


Airplanes flying upside-down.

So in the time preceding the race, this process was occurring off the coast of Japan and by the time racers were lined up on the track, water was standing around the entire circuit. This led to an exciting and dangerous race. Unfortunately, there was accident on the 42nd lap and one of the racers from team Marussia, Jules Bianchi, due to the wet conditions. Bianchi continues to be critical condition, more than 24 hours after the race.

It might not be a sport that many people follow here stateside, but it is far and away one of the most prone to weather related dangers.

Brendan Farmer

Blizzards and Their Dangers

With the bane of the Upper Midwest known as “winter” nearly upon us, I would like to take a moment to illustrate the different types of blizzards and why a blizzard is such a dangerous weather phenomena.

According to the National Weather Service, a blizzard is defined as a storm with large amounts of snow, which can be either wind blown or falling snow, winds at least 35 mph and visibilities of a 1/4 mile or less for an extended time of 3 hours or more. Normally the NWS with issue and advisory followed by a warning if blizzard conditions are expected to occur.If you see a warning, do not venture outdoors, as blizzards are extremely dangerous. Blizzards mainly form on the Northwest side of a storm system where strong pressure gradients can occur. Blizzards can occur anywhere where snowfall can occur, although they mainly occur on the Great plains and the Upper Midwest due to the fairly flat terrain and lack of trees.

Two main types of blizzard can occur, wind blown snow and falling snow. Blizzards from falling snow occur when the wind speeds are high enough at the NW edge of the storm to blow the snow significantly sideways as the snow falls. These storms can cause extremely large drifts to form very quickly due the facts that they are falling and can reach higher places forming large drifts. Blizzards caused by blown snow are drawn from snow that is already on the ground and is being blown around significantly. The danger from these storms is due to the very low level of the snow, which can cause havoc for those who are driving or walking. Snow blindness can occur in either which is a condition where the eyes are insufficiently protected from UV light (which snow naturally reflects a lot of) and as a result they develop a condition similar to sunburn that last for several hours and can lead to a diminished ability to see for a short time.

To wrap things up, be careful in the winter folks, and if you see a blizzard on the way, stay inside! They are not something to mess with, and they can be very dangerous.