Once in a Blue Moon…

July 29, 2015: “Once in a Blue Moon” is actually going to happen this Friday! More specifically, a full moon will occur late Thursday night into Friday morning.  The “Blue Moon” is the term for the 2nd full moon of the month (and not because it turns blue).

Click on image to enlarge.

Click on image to enlarge.

While the phrase “once in a blue moon” is used to describe something rare, the actual occurrence of a blue moon isn’t all that rare. The average lunar cycle (from full to new and back again) lunar cycle is 29 1/2 days, so almost every month can have 2 full moons if the timing is right. I say almost because February is the only month that can’t.  Sorry February; 28 days just doesn’t cut it.

The definition of the blue moon has changed a little within the last few decades.  It used to mean the 3rd full moon in a season (spring, summer, etc.) with 4 full moons. A misunderstanding eventually lead to the current definition of 2 full moons in a month. No matter what the moon is called this time around, see if you get the chance to take a peek and enjoy the view Thursday night!

– Alex

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Posted under event, science, space

This post was written by Alex Kirchner on July 29, 2015

Cold air funnels vs. tornadoes

June 29, 2015: The conditions in the atmosphere this afternoon brought some interesting weather to the Stateline. We saw funnel clouds of a few types around our area. To help with any curiosity or confusion over what we saw today, here’s the difference between cold air funnel clouds and tornadic funnel clouds (basically, two very different set of conditions in the atmosphere):

First off, what does a cold air funnel look like?  A few viewers provided snapshots of some of the cold air funnels in our area today.

Viewer photos of cold air funnels this afternoon. Click on image to enlarge.

 

Notice a couple things about the funnel clouds.  First off, see how high they are in the sky? And how small and puny they look?  These are some of the distinguishing characteristics of a cold air funnel cloud.  They are “high-based”, as we meteorologists like to call them, or that they form pretty far off the ground and high up in the storm or clouds.  Two, they look like a much bigger problem, but only get to be about that size, and remain small, weak-looking, and are slowly rotating. Cold air funnel clouds rarely reach the ground, and if they do, there is minimal to no damage. They only appear threatening, but are basically harmless.

Click on image to enlarge.

Click on image to enlarge.

How do they form? There has to be a shallow layer of cold air, BEHIND a cold front (this is a key difference from tornadoes, in that tornado-producing storms usually form along or AHEAD of a front).  There also has to be a little wind shear, or winds changing direction as you go up away from the ground. As the air from the surface rises, it spins a little in the weak shear, and if that air makes it to the cloud and fully condenses, you see a little, weak rotating cloud under the storm.

Click on image to enlarge.

Click on image to enlarge.

This is different from a tornado, in that a tornado needs much stronger wind shear, as well as plenty of warm, moist air to raise the instability in the atmosphere.  Unstable air can rise very quickly, getting the base of the storm to be lower.  This allows a much stronger rotation to be close to the surface, causing damage winds.

In summary, a cold air funnel forms much higher in the sky, is weakly rotating, and doesn’t pose much of a threat. A rotating funnel cloud spinning much faster and is much closer to the ground is most likely going to result in a tornado.

Tornado Warning for Lee County this evening. The conditions were much different in Lee Co. compared to elsewhere, so this type of rotation was threatening. Click on image to enlarge.

Tornado Warning for Lee County this evening. The conditions were much different in Lee Co. compared to elsewhere, so this type of rotation was threatening. Click on image to enlarge.

We saw both of these conditions today- the air near Rockford was cooler and weakly sheared, while the air in Lee Co. where we had a tornado warning for a while was much more humid, a little warmer, and had better shear.

So, how do you know the difference, and what should you do if you see a funnel cloud? Treat all funnel clouds with respect, and keep plenty of distance between you and them. The best advice is if you see a ROTATING (sometimes clouds hang low off of the storm, look like a funnel, but are harmless because they don’t rotate) storm cloud, check in with us online, on Facebook or Twitter, on-air, etc. and etc., or check to see if you weather radio is going off, your phone has an emergency alert on it, etc. We or the National Weather Service will let you know if that funnel cloud poses a threat or not. And remember, conditions can change in a hurry, or vary from location to location. Earlier in the day, the cold air funnels to the north did not pose a threat, but later in the afternoon there was a different set of conditions that sparked a potential tornado in Lee Co.  When in doubt, play it safe, get inside, and check in with us.

-Alex

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Posted under safety, science, severe weather, tornado, weather

This post was written by Alex Kirchner on June 29, 2015

Shifting Severe Threats

June 24, 2015: As mentioned yesterday, there are plenty of time when one round of thunderstorms has a direct impact on the next rounds coming after them. This can have major impacts on possible severe weather; we may see plenty of potential for severe weather, but have to wait to see how the pieces fall into place.

Tonight, strong thunderstorms are still possible, but not as likely as areas south of I-80 in central Illinois. The reason for the shift in the severe weather areas is all do to earlier rounds of thunderstorms.

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Click on image to enlarge

Several rounds of thunderstorms in Iowa this morning produced enough outflow to keep a warm front nearly stationary over Missouri.  The air behind that front is very unstable and would be needed to help fire off severe weather over us. However, the morning storms in Iowa plus a little activity that rolled through the Stateline this evening has kept us nice and cool, and pushed on the front enough to keep it in place.

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Severe weather chances for Wednesday night (June 24). Click on image to enlarge.

As a result, the best places for severe weather are now in southern Iowa and central Illinois, and away from us.  We could still get some strong storms and heavy rainfall, which could lead to flash flooding, but the risk isn’t as high as to our south.

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Click on image to enlarge.

Eventually, upper level winds will direct more unstable air towards us, so the strong storms in Iowa do eventually move in, but without the extra help from the warm front being close to us, we won’t see as explosive of development.

Keep the weather radio on and handy just in case overnight, and watch out for flooded roads tomorrow morning during your commute. However, we shouldn’t have to hold our breath as much tonight since conditions are looking better for severe weather in places that aren’t our backyard.

-Alex

 

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Posted under flooding, rain, science, severe weather, weather

This post was written by Alex Kirchner on June 24, 2015

Summer Solstice: June 21

June 20, 2015: The astronomical or “official” start of summer is here tomorrow! The summer season begins at 11:38 a.m., and is the longest day of the year.

SUMMER SOLSTICE

Click on image to enlarge

The Earth is tilted the most toward the sun in the Northern Hemisphere, giving us the most amount of daylight. In fact, the day is a whopping 6 hours longer than the Winter Solstice, or the shortest day of the year! The sun’s rays are also nearly 5 times stronger during this part of the summer, allowing us to heat up quickly during the day.  As we tilt away from the sun in the coming months, the sun’s rays get weaker as they have to travel a little farther through space to reach us.

Enjoy the extra rays, and here’s to summer!

-Alex

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Posted under science, statistics, sunlight, warm up, weather

This post was written by Alex Kirchner on June 19, 2015

Tropical “Storm” In Illinois

June 18, 2015: Tropical Storm Bill has been stirring up plenty of trouble with rain and wind since it made landfall in Texas earlier this week, and we may feel some of those impacts in our region. One of the advantages of living in the Midwest is NOT having to deal with tropical storms and hurricanes. However, every once in a while, one holds together just enough to provide the Midwest with a little rain.

bill path

Click on image to enlarge

You can see here that Bill started over the warm, moist air of the Gulf of Mexico, and made landfall this past Tuesday. Sustained winds were around 40 mph, but the wind gusts were in the 60 mph range. As Bill moves north, the storm will weaken, since the very warm and humid air of the Gulf won’t be feeding it any more. The storm essentially weakens into a strong low pressure system, similar to ones we get around here to bring us rain. What’s neat is that southern Illinois will be getting a taste of Bill this weekend!  The storm will not be nearly as strong, as you can see.

BILL 1

Click on image to enlarge

While Bill brings blustery winds, the bigger impact is the rainfall Bill is able to provide.  In fact, with most hurricanes and tropical storms, its not the winds that do the most damage, like you would think.  It’s the rain and flooding this storms can create. You can see in the radar image from Thursday evening that numerous flash flood warnings are out (in maroon), though a few severe thunderstorm warnings are occurring too (in orange).

bill precip

Click on image to enlarge

Here’s the 48-hour rainfall totals from the the stretch Bill has covered.  This doesn’t capture all of the rain Bill has dropped, but you get a decent picture that these storms can drop a ton of soaking rain, especially since they move pretty slow (Bill is only moving north at 11 mph), allowing the heavy showers to sit on places until they are flooding.  In fact, some areas in Texas saw 6″ to 10″ of rain, while in Oklahoma, certain areas had 4″ to 8″ of rainfall!

Bill will be much weaker by the time the storm reaches Illinois this Saturday, but a possible 2″ or more of rain may still fall as the weakening storm moves eastward.  The Stateline should be a little too far north to get rainfall from Bill, though we may get to see some of the clouds streaming off the storm over our area, which is a neat bonus.  It’s not often we get to say our weather is being influenced by a tropical system in these parts!

– Alex

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Posted under flooding, rain, science, tropical weather, weather

This post was written by Alex Kirchner on June 18, 2015

Project: Tornado 2015 Wrap-up

May 21, 2015: Project: Tornado has wrapped up for another year, as we visited our last school today. While this year’s round of presentations is over, our message about severe weather preparedness isn’t!  We’ll get to that in one second.

First, a special thanks goes out to all of the teachers, principals, and administrators that invited us to visit your school and students!  We had a great time talking to all of the eager and enthusiastic children in the Stateline we got to meet within the last 4 weeks.

project tornado

Overall, 4,176 students were taught about severe weather safety and tornadoes. Each student went home with a Project: Tornado book, so our hope is that for each student that reads and shares that book with their loved one, we reach many more thousands of people about the importance of weather awareness and safety.

Severe weather season is not over yet, so make sure you are always taking the proper steps to be aware and safe during severe weather, even though we haven’t had any since the April 9 tornado outbreak. This is the same message we shared with all of the students:

– have multiple ways to get weather alerts, such as the TV, radio, text message alerts, a weather app, and a weather radio.  You can sign up for text alerts at www.wrex.com/weather, download our 13 Weather Authority app for free for your smartphone, and we will hold several more weather radio events to program a radio for you.

– know where to go and what to do when severe weather strikes.  If you hear thunder, go indoors immediately. In the event of a severe thunderstorm, get inside and stay away from the windows. Know where to go in your house, work place, etc. if a tornado threatens.  You may only have minutes to act, so have a plan in place now.

– be weather aware: stay in-tune with the weather forecast, know when severe weather may threaten, and plan accordingly. If you see rapidly changing weather, it would be best to head indoors and check with 13 WREX for updates.

Thanks again to all of the schools we visited this year!  Look for sign-up for next year’s Project: Tornado sometime in March 2016.

– Alex

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Posted under event, Project: Tornado, safety, science, severe weather, tornado, weather

This post was written by Alex Kirchner on May 21, 2015

Cool May Weather

May 19, 2015: Conditions today felt more like March than May after a round of unseasonably cold weather slipped in behind a cold front on Sunday. The weather each day has been much cooler than the day before, dropping from the 80’s on Sunday to the 50’s today.

jet stream

The northern portion of the jet stream has dipped well southward, providing a quick spring chill to most of the upper Midwest and Great Plains states.

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Overall, we were 15 degrees below average today, and getting to be near record territory.  Today’s coldest high temperature was in the 40’s, so we were still 10 degrees off, but close enough to take a peek at the record books.

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Wednesday will not be much better.  The upper 50’s stick around because of the extensive cloud cover and the cold air not moving out yet.  We should have much more summer-like conditions by the holiday weekend.

-Alex

 

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Posted under cold blast, science, weather

This post was written by Alex Kirchner on May 19, 2015

Project: Tornado…The Final Days

The end is near, but the reason has only just begun!
Severe weather season is in full swing, and the 13 Weather Authority has been making sure Stateline students know how to handle it by continuing Project: Tornado.

Within the last three weeks, we have traveled to 19 schools across Northern Illinois educating elementary students on how thunderstorms form and how to stay safe during a tornado. As of today, roughly 2,651 students are prepared for severe weather, and we’re still not done!
Next week, we finish off our final week of Project: Tornado, as we head to Spring Creek Elementary, Rolling Green, Barbour Language Academy, Swan Hillman and St. Mary’s School to educate another 1,200 students. This means almost 4,000 Stateline students will know exactly what to do when severe weather strikes.

Each student receives a Project: Tornado booklet, filled with pictures, games, and important information to help them understand thunderstorm processes, tornadoes, safety, and local historic tornadoes.
Here’s a sneak peek:

PT1 PT2 PT3

 

 

 

 

 

 

PT4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

‘Severe weather ready’ students are from Conklin Elementary, Perry Elementary, Pecatonica Elementary, Keith Country Day, Jefferson Elementary, Immanuel Lutheran School, Ellis Arts Academy, Lincoln-Douglas Elementary, Rockford Lutheran Academy, Thurgood Marshall School, Ralston Elementary, C. Henry Bloom, Holy Family Catholic School, West View Elementary, Shirland School, Highland Grade School, Loves Park Elementary, Lewis Lemon Elementary, and Nashold Elementary.

ptlewislemon

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Posted under event, Exactrack|HD, history, Project: Tornado, safety, science, severe weather, tornado, weather, weather geek, Wind

This post was written by Morgan Kolkmeyer on May 15, 2015

A Look Back 48 Years Ago and 11 Days Ago

We are 11 days removed from the EF-4 tornado that ripped through north central Illinois, beginning in Franklin Grove, stretching 43.5 miles through Flagg and into Fairdale. While locals and non-locals are pitching in on the effort of recovery for residents affected by 7 tornadoes on April 9th 2015, many are also remembering the devastation from a tornado that struck the Stateline nearly 48 years ago.

On April 21st, 1967 the city of Belvidere experienced a deadly tornado, with eerily similar damage to the EF-4 tornado on April 9th 2015, but this one was twelve times as deadly.

Let’s flash back to meteorology in the 1900’s. Right after World War 11, the weather community started the use of radars, which were around for about 30 years by the time the Belvidere Tornado occured.
4-9 radar imageIn 1948, less than 20 years before the 1967 tornado, Robert C. Miller and E. J. Fawbush correctly predicted the first tornado in Oklahoma.  10-15 years before the Belvidere Tornado, computers ran their first models of the atmosphere. Just 5 years before the deadly tornado hit Boone County, Keith Browning and Frank Ludlam published a detailed study of a supercell storm, the first one of it’s kind. In fact, it wasn’t until a few years after the Belvidere tornado that Dr. Tetsuya Theodore Fujita invented the “Fujita Scale.”

Are you catching my drift here? While the foundation and structure of much of meteorology was founded, knowledge and awareness was minimal on the atmosphere during the early and mid 20th century. This is a key contributor to the saved lives and safety of many Stateliners on April 9th 2015.

The tornado that devastated Boone County 48 years ago was rated an “F-4″ on the Fujita Scale. According to the Fujita Scale, an F-4 tornado *estimates wind speeds between 207 and 260 mph, and typical damage includes well-constructed houses leveled, weak foundation structures blown away, and cars thrown. We now know that the Fujita Scale could over-estimate wind speeds, which is why we now use the Enhanced Fujita Scale (another educational advancement).

Still, the damage we see in photos of the Belvidere Tornado in 1967 grimly mimic the photos being posted from Fairdale within the past 11 days.

According to Jim Allsopp, Warning Coordination Meteorologist at the National Weather Service, the Belvidere Tornado first struck just before 4PM 2 miles southeast of Cherry Valley. It went on to destroy 300 new cars and 100 employee cars at the Chrysler Plant, which was only a fraction of the damage it would go on to create. The tornado moved on to the southeast side of Belvidere, where 127 homes were destroyed and hundreds more were damaged.

At the time, Belvidere High School had just dismissed students onto buses filled with elementary school students. 12 buses were rolled over and children were flung into muddy fields.
belvtor2

 

In 2011, Ken Anderson (left) told WREX, “My bus (#30) was moved 100 yards by the tornado. I was wedged under a seat, my shirt soaked red with blood. I saw one, little body half buried in the mud. That memory, an 11 year old should never witness. In this picture, I am on the left (shirt tail out). That concerned look on my face marked the end of my childhood.” At Belvidere High School, 13 people were killed and another 300 were injured, which was just a little more than half of the havoc caused that day.

 

 

 

Dale Marks also vividly remembers April 21st 1967, “They tell me I was lucky. I only had both legs and pelvis broken. Our bus was just on the north side of the school. I think there were five people killed on my bus.’
belvtor1The Belvidere Tornado of 1967 went on to kill a total of 24 people and injure another 500.
To read Jim Allsopp’s full synopsis of the event, click here. To read all of the survivor comments from 2011, click here.

 

 

The Belvidere Tornado of 1967 was an F-4 and was up to 1/2 mile wide. It traveled 25-28 miles on the ground.
fairdale1The tornado that hit Fairdale (left) eleven days ago was an EF-4 that was nearly 1/2 mile wide. It traveled 30 miles on the ground.
But, what about the fatalities and injuries? During the 1967 F-4, 24 people were killed and another 500 were injured. During the 2015 EF-4, 2 people were killed and 22 were injured.

 

 

 

 

 

 

Education and awareness are saving people’s lives.

The Storm Prediction Center was able to put out the risk of severe weather nearly a week ahead of the April 9th event. The Chicago National Weather Service was able to implement watches and warnings with ample time to get to safety before these tornadoes struck communities. In fact, Ogle County Sheriff Brian Van Vickle stated, “I don’t think you could’ve asked for better warning.” Local TV meteorologists were able to give in depth explanations on air and online about WHY that Thursday could end with severe weather. We all could do this because of advancements in the world of meteorology.
4-9 radar image 2

In my opinion, the most important thing meteorologists can do is continue to explain to you WHY we could see dangerous weather, WHY we saw dangerous weather, or WHY we ended up not seeing dangerous weather. We’re living in a world with Google at our fingertips, with politics overlapping into sciences, and with education being pushed on everyone. We have been raised and trained to ask questions. Why would you believe something just because someone told you? You have the right to question. I think it’s our job to explain to you why it’s a threat, not just the fact that it’s a threat.

In my opinion, one of the most important things we as a community can learn from both of these deadly tornadoes, is the importance of heeding warnings and continuing to educate yourselves and listening to “the why” instead of chalking it up to “sensationalism,” “hype,” and even “TV ratings.”

Because awareness and education is one of the biggest contributing factors in the difference in death and injuries during severe weather.

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Posted under event, history, news, safety, science, severe weather, statistics, tornado, weather, weather geek

This post was written by Morgan Kolkmeyer on April 20, 2015

Record dry air (nearby)

April 14, 2015: Did the air feel really dry today to you? It did in Chicago today, where the dry air tied a record at O’Hare airport.  The relative humidity dropped to 13%, which tied April 8, 1971, April 11, 1956, and May 10, 1934 for the driest relative humidity on record for Chicago. For reference, the human body generally feels comfortable at 45% relative humidity, so 13% is very dry!

Relative humidity readings at 4 pm today

Relative humidity readings at 4 pm today

If you are wondering what or how we figure out the relative humidity of the air, here’s a crash course (get ready for a lot of science!): humidity describes how much water vapor is in the air. We can measure this with absolute humidity, which is the mass of water vapor divided by the mass of dry air at a certain temperature. The hotter the air, the more water vapor it can hold, and so the value for absolute humidity is higher.

To get to relative humidity, we use the ratio of the current absolute humidity to the highest possible absolute humidity at that temperature. At 100% relative humidity, the air is completely saturated and can’t hold any more water, usually creating rainfall as the moisture falls out of the air.

An area of high pressure results in downward movement in the atmosphere. This dries the air out, and is why we don't usually have clouds or active weather under high pressure.

An area of high pressure results in downward movement in the atmosphere. This dries the air out, and is why we don’t usually have clouds or active weather under high pressure.

Why did the air feel so dry today? We did have an area of high pressure right overhead, which may have contributed to the dry conditions. High pressure promotes downward movement in the atmosphere, which counteracts what you may have learned in elementary school about the water cycle- instead of the air rising, then cooling and condensing into clouds, downward moving air dries out.  This is one of the reasons why the air was so dry today.

-Alex

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Posted under event, record weather, science, weather

This post was written by Alex Kirchner on April 14, 2015