As a meteorologist, hearing and speaking “weather lingo” has become a part of my daily life.  Just ask my wife!  On a day during the summer when severe weather is possible, I flip some proverbial switch that launches me into full weather nerd mode.  When she asks when the storms will hit, I’ll tell her when, but only after I explain how the increasing instability, appropriate wind shear, wet-bulb zero heights near 8,000 AGL and plentiful moisture will make it a busy day at the weather office.   At first, she used to tell me to “tone it down.”  Now, she flips her filter “switch,” picks up her book, reads a few pages, and waits for the punch-line.  Smart woman.    But when it comes to expecting precipitation, there’s one term I don’t mention very often around her, or even with my family and friends: “percent chance.”

Knowing the “percent chance” of an upcoming event is important to many people.  However, some people who put faith in this number mistakenly interpret the true definition of “percent chance” in weather terms.  If I go out on the street and ask people what it means if there’s a 30% chance of rain or snow today, a majority will probably say it means 30% of the area will receive rain or snow, while the other 70% will stay dry.  It’s a good try, but a complete miss.

The percent chance of precipitation is also known as the probability of precipitation. (POP)  The National Weather Service has been using POPs for decades, assigning them to daily forecasts.  Basically, when a meteorologist says “there’s a 30% chance of rain today,” it means there’s a 30% chance any random point in a given area will experience measurable precipitation.   And the number isn’t just pulled out of the air.  (Pun intended, of course!)  The number 30 is determined by forecasters and computer models.   It means three out of ten times when conditions were similar in the past, it rained.  So yes, the higher the percentage, the more likely precipitation will occur, but it all depends on the size and history of your forecast area.

So why the confusion?  A large part of the problem is the lack of explanation by broadcasters and internet resources.  You’ll rarely hear from a broadcaster what percent chance means; or, worse yet, the broadcast does not correctly understand the whole concept.  On internet forecast pages with percent chance listed, there’s usually no written statement next to the forecast, explaining it’s probability rather than coverage area.  The lack of explanation, combined with human nature’s urge to jump to conclusions, can lead to a misunderstanding of what the meteorologist or broadcaster is trying to relay.

The WQOW News 18 forecast team frequently displays the precipitation risk.  You’ll hear mentions of “slight, moderate, and likely.”  Once in a blue moon, a  number is mentioned, but you’ll more likely hear terms such as isolated, scattered, hit and miss, widespread, etc.

I have many friends and colleagues that live by percent chance.  That’s perfectly fine and I don’t disapprove of their method.  Their forecasts have a lot of good, quality information too.  A POP is there to provide the meteorologist an understanding of what the atmospheric setup is like.  In my personal opinion, the reason that specific number does not make it to air is because I feel avoiding an exact percent chance as much as possible provides you, the viewer, a better idea what the weather will be like.  Remember the whole area thing?  News 18′s viewing area is far different compared to other media outlets.  It’s also not fair to write on a graphic “50%,” when that chance exists closer to Rice Lake compared to the “10%” that would exist in Eau Claire.  Second, it can be very confusing!  I am a big fan of taking the complexity of numbers and equations and making a forecast that’s easy to understand.  More or less, you’re just trying to find out if it will rain or snow, right?  So why make your experience of understanding the weather forecast similar to writing a college mid-term?  No thanks!

Thanks for reading, and feel free to post with comments or questions!  Stay tuned for more from Beyond the Forecast…

Posted under Hometown Weather

There’s no doubting it.  Thursday morning was extremely cold in western Wisconsin.  Sure, there are times during the winter when the temperature overnight tumbles into the double digits below zero.  But when you add a decent wind into the equation, the situation turns from plain cold to dangerous.  Wind chills of -25 to -30 were recorded across western Wisconsin during the early morning hours.  In those conditions, a person not dressed properly would have experienced frostbite or hypothermia in a matter of minutes.

In my opinion, our forecast regarding the dangerous cold came with ample warning time.  We continued to provide updates during the coldest period, letting the public know what to expect and how long the danger would last.  You may have noticed though no cold weather advisories or warnings were issued by the National Weather Service for the Chippewa Valley.  The reason: a new experimental program that ditches the Wind Chill Advisory and Wind Chill Warning for the “Extreme Cold Warning.”

Figure 1 - Warnings/Advisories for night of 1/18/2012

Thursday Morning's Wind Chills (1/19/2012)

In summary, Eau Claire would have been included in a Wind Chill Advisory in the past.  But because “Wind Chill Advisory” does not exist in the Chanhassen “language” anymore, no cold weather alerts were issued, even though wind chills were just as cold compared to locations in the Wind Chill Advisory, like Medford, Neillsville, Osseo and Mondovi.

Posted under Hometown Weather, Weather

As you know, salt is a life saver during the snowy months.  For most of us, the reason is self-explanatory: it helps clear up the ice, making way for safer travel by vehicle or by foot.

But salt doesn’t always work.  In fact, there are a few times during the year road crews will stop spreading salt and will start using sand.  Of course, the switch only goes so far.  The roads are still in rough traveling shape, because no matter how much sand is dispersed, the ice is always present.

So why does salt not always work?  Well, salt doesn’t melt ice through some kind of special chemical reaction.  Salt, or sodium chloride as it’s known as a chemical compound, lowers the freezing point of water, from 32°F to near 0°F.  When tossed onto ice, the melting process begins immediately.  At first, a layer of water forms around the salt crystals.  Over time, the salt slowly dissolves into the water, creating a saltwater solution.  This increases the rate of melting.  In other words, once you spread salt, the process just kind of snowballs until the ice is gone.

There are a few products for sale that lower the freezing point of water colder than 0F.  Some communities and private organizations have used these products, and there’s been a lot of success.  However, it you’re a county or city on a tight budget, the goal is the most bang for your buck.  You never know how much snow will fall, or if old man winter will take a spring vacation to the Midwest.

So, when you head out and the temperture is below zero, especially after a snow storm, know that there’s going to be a lot of ice on the roads.  Thankfully, the ice won’t be as slippery compared to when it’s warmer outside.  That’s a topic for another blog post coming up later this winter.

Check out this video: Salt vs. Bitter-cold.  A blast from the past, from my first time working at WQOW!  This story aired on January 18, 2008.  The expertise is provided by Mike Barnhardt, Street Maintenance Manager, now retired.  I was only four months on the job…you’ll notice I may be a little green yet!   But the point remains the same.

Thanks for reading and have a great weekend!  Stay tuned for more from Beyond the Forecast…

Posted under Hometown Weather, Weather

9:20 AM, January 12.  Temperature: 11°, wind chill: -1°.

Yes, it does feel cold outside!  With highs today only reaching the middle teens and strong northwest winds, some would say it’s downright brutal outside.

This certainly isn’t the coldest weather we’ve experienced in the Chippewa Valley.  In fact, our low temperature average for this time of the year is 5°, while our average high is 23°.  But with readings in the 40s and low 50s earlier this week, you can’t help but feel chilled to the bone!  At least I do.  I don’t mind the snow, but I really don’t like the colder weather, especially when the utility bill comes.  There must be a mouse or a hamster spinning that wheel for me in the electric meter…

The talk about arctic air’s return has me thinking about something we haven’t discussed much this winter: wind chill.  The last few years, wind chill readings from -15° to -30° were not unheard of in western Wisconsin.  This year, as you know, it’s a different story.  But as I take a quick look at the long range temperature projections, I can tell you wind chill is something we’ll have to get a little more used to again.

Wind Chill Chart --- Courtesy: National Weather Service

Most have a basic understanding of wind chill, but if you don’t, that’s perfectly fine.  In short, the colder and winder conditions are, the colder it feels outside.  Check out the chart on the left, courtesy of the National Weather Service.  If the morning temperature is 0° and the wind is northwest at 15 mph, the wind chill is -19°.   Hopefully never this case, but -20° with a 15 mph wind, the wind chill will be -45°.  Why is the wind chill important?  If you study the chart, you’ll see different colors.  Frostbite can always occur anytime the temperature is below freezing, but it the process is much quicker when the wind chill is -18° or colder.

I’ll end today’s blog post with a trivia question I hope you’ll take a stab at.  Even if you don’t have a clue, don’t be afraid to chime in explaining how the cold affects you.  I would love to hear from you, and part of my job is helping people understand weather.  And, no cheating!   Stay tuned for more from Beyond the Forecast…

Posted under Hometown Weather, Weather

I  just learned a neat fact today.  Did you know last winter $2.1 billion was spent on tourism?**  Yes, billion with a “B”.  It’s a bigger number than I would have guessed!  Now, break that number down over the season, and on average, tourists spent about $20 million per day.  Wow!  Last season, that kind of green during a period of white certainly put a smile on many business that depend on winter tourism.

I’ll admit: I like mild weather, but I love the snow too.  However, after a few cold and snowy winters, I thought the recent mild patterns were a nice change of pace.  Unfortunately, my thoughts aren’t exactly helpful to businesses that depend on winter tourism.  When I look outside the window (blog post written pre-snowfall), I don’t really think of winter.  I think of spring, and spring activities like jogging, biking, prepping the garden, etc.  I’m sure many of you think of spring too.  Yes, the physical lack of snow has hit some winter recreation businesses hard.  But one has to admit the brown ground doesn’t help the mood!  Many businesses are open, pleading with people to come enjoy what they have to offer.

View from Christie Mountain near Bruce, WI (1/11/2012)

Let me give you a real life example.  My uncle, a ski instructor at a ski hill in northwest Wisconsin, wrote me an email, telling me they were open for business.  A paraphrased version, here’s what he wrote:

 “We are 100% open to skiing, snowboarding, and snowtubing!  Also, the crosscounty skiers are using the 12 miles of trail that is north of the hill.  So pass this on to whoever needs to see it.  It would make a great story on the nightly news that “YES” we still have winter.  Send them up!”

His ski hill, like most, makes their own snow.  In fact, the latest report states a 22″ base will all lifts running and nearly all trails open.  You could never guess that just by looking outside. 

There’s plenty of natural snow in Wisconsin too; you just have to know where to find it.  Since December 1st, Eau Claire has only received 7.7″ of snow.  Did you know in the same time frame, Hurley, WI has accumulated 30.0″?  Neighbor Eagle River hasn’t done too bad too, though much less – 16.5″.  Of course, these two locations are in far northern Wisconsin, in the Lake Superior snowbelt.  They typically receive 55″ to 65″ per year, about half credited to lake-effect snow.

Most Ski Hills in Good Shape in Wisconsin --- Image Courtesy: Wisconsin Dept. of Tourism

I had a nice phone conversation with a representative from the Wisconsin Department of Tourism this morning.  She told me they are “not too worried yet,” and that the tourism industry in Wisconsin is quite resilient.  She stated many small businesses have done a good job adapting to mild and dry weather streaks, offering additional products or unique promotions.  She said it’s the hotels, restaurants, snack shops – businesses of that nature – that have taken the biggest hit.  Think of it…if you’re a skier and you stop for snacks along the way or to gas up…it makes a difference!

Now, to find those snowshoes…looks like I’ll have to get the ladder!  Thanks for reading and safe travels tonight and tomorrow.  The roads will be icy.  Stay tuned for more from Beyond the Forecast…

**Figure provided by Wisconsin Department of Tourism

Posted under Hometown Weather, Weather

Fact: today is January 10th.  I know that because I checked the calendar this morning. ;-)  Plus, I’ve been counting down the days to my birthday, which is tomorrow, the 11th.  I just seemed like I was just celebrating my birthday.  My, how the time flies!  Ok, I digress…

January 10th: you know as well as I do it doesn’t feel like January outside!  Today, we will break shatter our standing high temperature record of 45 established in 1980.  With highs in the upper 40s and lows in the 20s, one could arguably claim it’s late March.  It’s absolutely unbelieveable!  In all my memory, I can’t remember a time when daytime highs were constantly in the 30s and 40s in early January.  In addition, I can’t remember a time when the first day of winter came and went, and we haven’t had a whole lot of snow to show for it.  Can you?

I don’t want to bore you with statistics, because we science people are good at that.  But just roll with me for a second.  Let’s consider December 2011 alone.  Last month, the overall, average temperature (mean) was 32.6 degrees, more than five degrees above the normal.  Think about that for a moment, and also note the mean temperature was above freezing!  It’s certainly not our warmest December on record; that happened in 1931.  But quite impressive!  So far, January’s mean temperature is 25.7 degrees, more than 10 degrees above  normal.

Many are asking: why in the world is it so warm outside?  Well, the “world” has a lot to with it.  I’m not talking about climate change, a topic I do want to discuss in the future, but from an unbiased point of view.  In short, I’m talking about the position of the polar jetstream, combined with other weather events.

Figure 1: Current track of Jetstreams. Polar jet is blue, subtropical jet is orange.

Take a look at Figure 1.  In general, the jetstream is a current of fast moving air in the higher levels of the atmosphere.  There are two jetstreams in each hemisphere, the polar and subtropical.  The polar jet is the strongest because is supported by the large temperature difference between the poles and mid-latitudes.  Meanwhile, the subtropical jet’s main driving force is Earth’s rotation.  My point: the jetstreams, especially the polar jet, separate colder air from warmer air.  As you see in Figure 1, the polar jet is positioned north of Wisconsin, meaning mild temperatures for us!

There’s a lot of discussion as to why the polar jet is north of us.  The most agreed upon theory is the Madden/Julian Oscillation.  (MJO)  I know, big phrase, and it’s even bigger problem to describe given its complexity.  The bottomline is the MJO is a pressure disturbance in the tropics that can modify the track of the jetstreams.  In our case, the disturbance, now located in the Pacific, is causing the polar jet to track north of the Midwest.

Figure 2: Three Month Precipitation Forecast, NA. Green (above average)/ Orange (below average) Courtesy: Climate Prediction Center

Looking ahead, with an incoming cold front Wednesday morning, temperatures will dive below the seasonal average.  Thursday and Friday, we’ll be lucky to make it into the upper teens, 30 degrees colder compared to today and Monday.  But this cold snap is just a short-term deal.  For one, there’s no snow on the ground, so our temperature can rise quickly with the sun’s help.  Secondly, the Climate Prediction Center (CPC) suggests temperatures will remain at or just above average through the rest of the winter season – back to the whole MJO thing.  The center does suggest near or above average precipitation though.  That’s good, in my opinion.  Since December 1, we’ve received less than a foot of snow, less than a decent winter storm.  Unbelievable…

Stay tuned for more from Beyond the Forecast…

Posted under Hometown Weather, Weather

Well, to say “new station” is kind of misleading.  If you’re an avid watcher of WQOW News 18, you may remember I was the weekend meteorologist from 2007 through most of 2009.  After a short leave of two and a half years, working on the morning show at our sister station WXOW in La Crosse, I’m back in Eau Claire.  It feels great to be part of the community again!  I hope 2012 is starting well for you, and I wish you best of luck and a prosperous new year.

For me, a new year not only brings a new job, but also a new opportunity to connect with you, my friends and neighbors.  In addition to my work on air and online, I’ll be keeping this neat blog called Beyond the Forecast.  Please, feel free to bookmark this blog, because I will be sharing some cool things along the way that you won’t want to miss!  If you’re an avid computer user like me, you sometimes need a go-to place online.  That’s my goal with this blog.  I’ll not only talk about the short and long range forecast, but we’ll get into some weird and cool science too.  I promise I won’t make it difficult, just fun!  I’m not limited to science either; discussions regarding the Chippewa Valley, news, and sports are not off the table!

Some things about me:  I graduated from UW-Madison with my Meteorology degree in 2007 and I earned the Certified Broadcast Meteorologist designation from the American Meteorological Society in 2009.  I love anything relating to the Wisconsin Badgers, the Packers, good food, great conversation, and fun.  My wife Britny and I were married in Eau Claire in July 2010, and we both grew up in a rural community just northeast of Eau Claire.  We are quite familiar with the area, but love meeting more people.  If you see us out and about, never be afraid to say hi!

So, stay tuned for a look Beyond the Forecast….

Nick

Posted under Hometown Weather, Weather