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Don’t be distracted by the shine.

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We seem to live in a world of extremes these days. If you don’t absolutely love or absolutely hate something, the suggestion is that you just haven’t made up your mind. While there is a “like” button on Facebook, just being lukewarm to an idea is portrayed the same way as being totally against it in many news outlets and blogs. So, instead of focusing on the merits of both sides of the coin, we’re told we must pick heads or tails and there can be no in-between.

I want to remind the world it takes two sides to make a complete coin. So, let’s focus for a minute on something more substantive than the shiny sides by considering what the coin represents – a topic with important implications for everyone.

What do anthropogenic climate change “skeptics” and “believers” have in common? While most media outlets would have you think the answer is “nothing,” it’s far from true.

No matter which side of the debate you lean toward – human-caused warming versus natural variation – the ultimate goal of both sides should be mitigation of present and future risk. I’ve written about this topic before, but with recent articles about the U.S. government’s Climate Science Special Report, the likelihood of more hurricane Harvey-type storms, and how important changes in non-extreme rainy and dry spells are to the climate, I feel safe revisiting this subject.

Harvey

Image credit: NASA. A satellite image shows Hurricane Harvey as a Category 4 storm on August 25, 2017.

Case in point: when the Climate Science Special Report was released, it was taken by many at face value and reported with a tone of urgency and alarm by most news channels. However, other scientists such as Steve Koonin, who wrote a post about it for the Wall Street Journal, and Judith Curry, a climate scientist often called a “lukewarmer” because she questions how much faith we should put in climate models she knows intimately, looked at it with a more discerning eye. They questioned the timeline used in the report with regard to sea level rise. The report looked at the late 20th century through the early 21st, but apparently ignored higher sea levels that existed in the first part of the 20th century. That framing of the study has caused concern and become yet another topic of debate.

What both sides agree on, though, is that with rising sea level of any amount, coastal areas need to look closely at land-use policy and engineering to best protect their populations and natural resources.

Houston is a prime example, especially since an article on The Atlantic’s website published this week claims that with a warming climate, storms like Harvey will be much more likely to happen than they once did. While Harvey had a devastating effect on Houston, I can’t help but question some of the logic in that article, which was based on a rushed-to-print study by a well-respected scientist. I recall the dire warnings during the historic hurricane season of 2005 – how that season would set the tone for every year thereafter because it heralded the worst-case scenario for a warming climate. It took 12 years for us to see another season of landfalling, monster storms, and even this year wasn’t as bad as 2005. Not that I’m complaining.

Houston’s situation is more complicated than many coastal cities because Houston is sinking. Poor judgement in land-use for a quickly growing population over decades in the form of groundwater withdrawal has caused subsidence, especially in northwestern Harris County. Houston’s exposure to flood risk has been exacerbated by its sinking. A report published in 2010 cites a difference in ground elevation for that area of 2.5 meters between the 1930s and the 1970s. That change is huge! This fact isn’t news to Houston residents, but it probably is to most people outside of that region.

By the way, the report on Harvey’s effect on Houston was rushed so that it could be used by planners and engineers in the rebuilding process for the purpose of mitigating risk. Can you blame them?

I have always been one to weigh both sides of an argument. I learned the importance of being able to argue any point in debate class in tenth grade. If you don’t understand all aspects, you are making decisions based on incomplete information. So, please, don’t just choose heads or tails because one is shinier than the other. Consider the whole coin and understand that there’s value to it as a whole.

Weather Blog

Today’s high temperature could beat a record

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Like all scientists, meteorologist love data. We keep records for as many things and as many places as possible. We have daily maximum and minimum temperature and rainfall records going back over a century.

dreary fall day

The view from the author’s office window on a dreary, colder-than-normal November 8.

When you collect that much information, you’re able to compare dates year-over-year and extract other useful information, too. For example, two of my favorite records to consider are the lowest maximum temperature and the highest minimum temperature. They give an idea of whether a day has really been “this cold” or a night really has been “this warm” on a particular date in the past.

When we have a day like today – cold, dreary, damp, and winter-like in early November, I always look at the lowest maximum temperature records to see how unusual the weather really is. Today’s weather could actually be noteworthy, especially since we’re not expecting the temperature to move much at all day.

The official climate records for the greater Triangle are kept at Raleigh-Durham International Airport, so even though we are not necessarily at that location, that’s where we have to look. On this day in 1971, the high temperature was 46 degrees – the record for the lowest maximum temperature for the day. The runners-up are 48 degrees in 1933 and 50 degrees in more than one year. So, if we stay cooler than 46 degrees today, we will break that record for the coolest high temperature on this date.

In case you are wondering, our normal (30-year average) high temperature for today is 66 degrees, and our normal low is 43 degrees. Yes, this is definitely an unusually chilly day.

Weather Blog

Late October storms can be devastating

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This weekend, Minnesota had the earliest snowfall of the season since 2009. It caused more than 300 auto accidents and spinouts across the state. As the low-pressure system that caused that snowfall moved eastward, the trailing cold front joined up with the remnants of Tropical Storm Philippe causing that center of low pressure to move northward up the east coast.

sat image

Experimental product from the new GOES-16 satellite system and the National Weather Service showing the massive storm over New England the morning of October 30, 2017

By this morning, the resulting massive storm had left over one million customers without power from the northern Mid-Atlantic states into New England. Heavy rains and high winds caused flooding, downed trees, and additional accidents.

All of this happened on the weekend we observed the five-year anniversary of Superstorm Sandy. Sandy was a hurricane that hit the northeast coast directly, became extra-tropical, and was devastating on a larger level, being credited for 233 deaths and $75 billion in damages.

Tropical storms and hurricanes that make landfall are disastrous on their own, but when they collide and/or combine with other storm systems – such as a strong cold front – they become even more powerful. The moisture content of the tropical storms adds to the potential for extreme precipitation events, which could take the form of torrential, flooding downpours or heavy snow depending on the temperature. This weekend, residents of New England avoided the addition of the snowfall that accompanied Sandy. While those affected would probably not call themselves “lucky,” it clearly could have been worse.

I doubt we’ll see a fatality count recorded from this weekend’s system the way that we did with Superstorm Sandy, but I read there were four in Minnesota and I personally know of one here in North Carolina that can be blamed on the weather. I would not be surprised if there were more that haven’t been tallied nationally, yet. It goes without saying that those five are five too many.

Weather Blog

Fall finally arrives!

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Did you have frost on your pumpkin this morning? Growing up in the deep south, that’s how I knew that fall weather had settled in. Of course, if you don’t have pumpkins, grass works just as well.

metar reports

This map shows reports of area conditions at 7:20 AM on October 18, 2017. Temperatures across the region are shown in red. The dew points are shown in green.

By the calendar, climatological autumn started on September 1, and astronomical autumn began with the Equinox on September 22. However, you know in the south, we still wear white after Labor Day, a white Christmas usually equates to the dominant color of decorations, and you don’t need a sweater at a football game until at least mid-October.

This morning was the first one this season that we had state-wide reports of temperatures cold enough for frost to form. How does today measure up to the average day for first frost? It’s a little on the early side for Wake County. I couldn’t find specific dates for Wake Forest or Creedmoor because neither has an official reporting station, so I had to go with the Raleigh-Durham airport’s numbers.

According to a North Carolina State Extension Publication, “Average First Fall Frost Dates for Selected North Carolina Locations,” the average date of first frost at RDU is October 27. Today is 9 days ahead of that date, so it is a little earlier than normal.

I’m sure someone reading this is wondering what an early frost means with respect to the winter. It really doesn’t mean anything. Frost in our area just shows that we experienced a cold night with not much wind and enough moisture on surfaces to freeze. The high pressure that is controlling our weather this week has set us up for dramatically cool temperatures overnight. As humidity starts to rise this weekend, our nighttime temperatures will start to creep back up, and it could be a while before we see frost again.

Weather Blog

A Gen Xer’s thoughts on GENX

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Do you remember back in ’69 when Lake Erie caught fire? Honestly, I don’t. It happened 5 years before I was born. However, I do remember hearing the story and until today, I thought the song “Smoke on the Water” was about that event.

Okay, I’ll admit I was wrong about that. I’m much better at 1980s music trivia, I promise.

As a further correction to my inaccurate memory of hearing the story somewhere years ago, what really caught fire was the Cuyahoga River, which feeds into Lake Erie. For those like me who don’t quite remember why, factory pollution, agricultural runoff, and sewage used to be common contaminants in waterways – so common that occasionally, those pollutants and contaminants were visually evident in the form of fire on the water.

According to ClevelandHistorical.org, the burning river was one of the events that lead to the passage of the Clean Water Act by Congress in 1972, as well as the Great Lakes Water Quality Agreement by the United States and Canada.

Sometimes it takes dramatic visual evidence to bring people’s attention to a problem, especially one that took years to develop.

Lake Erie

The author’s view of a small part of a pretty clean Lake Erie, standing beside The Rock and Roll Hall of Fame and looking toward FirstEnergy Stadium in Cleveland, Ohio, on October 10, 2014.

The river and Lake Erie are much cleaner these days. Unfortunately, it took laws, regulatory code, and watchdog groups to get it back into shape. There is a legitimate reason to have the Environmental Protection Agency and the Department of Environmental Quality. As much as I’d like to think that we are past the age of people dumping pollution or allowing leakage of contaminants into bodies of water, especially those that provide drinking water, I know there will always be some person or organization who will do it because they think they can get away with it.

My generation doesn’t remember much about life before all the regulations. And the Millennials? They’ve always had them. While I don’t necessarily think we need the government to control all our actions, I do think a little regulation goes along way, and that thought is based on the evidence.

Flash-forward from the late 1960s to the news of the present era – a spinoff company of Dupont was dumping an as-yet unregulated chemical called GENX into the Cape Fear River. This particular compound is a technology used in the of the creation of non-stick coating on cookware, mobile phones, and laptops among other products. Testing has shown that the amount in the water is minimal and unlikely to cause harm to humans at current levels. That reality is not squelching the outrage that a company thinks it’s okay to dump pollution into the water just because the particular type of pollution has yet to be named and coded into regulation. People downstream have the right to be unhappy about it.

The question is whether they realize they are up in arms about the wrong contaminant. GENX would need to be present in a level 100 times greater than it is now to do real harm.

According to a news story on WRAL.com published on July 28, 2017:

“The Cape Fear River is full of unregulated chemical byproducts, Knappe said, noting his main research has been into 1,4 dioxane, which is produced during the manufacture of plastics and polyester. The EPA has labeled the compound a likely human carcinogen linked to kidney and testicular cancer.

1,4 dioxane is a component of commercial solvents like trichloroethylene. In the past, it’s been most commonly found contaminating groundwater when it leaks from underground storage tanks. But Knappe says it’s also currently being discharged into the Cape Fear watershed by manufacturing operations in the Triad.”

WRAL explains that Detlef Knappe, who is quoted in the excerpt from their story above, is “a professor of civil, construction and environmental engineering at N.C. State and one of the state’s top researchers for Gen X and other contaminants in drinking water.”

So, why is GENX making the news and being discussed in the state legislature when at least one much more dangerous substance is in the water at much higher levels?  As the marketing campaign asked back in the 80s, “Inquiring minds want to know.”

I have my ideas, which include the fact that GENX is easier to say and remember than some of those proven carcinogens that are also in the water. It’s news to the people downstream who have been arguably imbibing it with their drinking water for at least three plus years, but didn’t learn about it until this year. They are (understandably) mad and demanding something be done. They want regulation and reparation, so GENX is part of this year’s breaking news cycle and a top story of the summer.

I also wonder if some people are taking the story and running with it because they want to point to a recent, popular topic as a reason not to cut funding to the EPA. We’ve seen this year that science is a touchy and highly political subject, like it or not. Any story from a scientific perspective that can be used to support an argument in one way or another for the funding of an agency that isn’t quite loved by the current presidential administration will get more aggressive play in the media than those that aren’t.

Maybe it’s true, but I am claiming the previous two paragraphs as pure speculation on my part because I have no evidence. I will be the first to admit that, so don’t quote me as knowing anything that I don’t.

What I do know is that the EPA and the DEQ still have their place in this world as long as people, companies, and organizations still do things that most of the rest of us consider irresponsible and wrong just because they think they might get away with it.

Weather Blog

Weather has new relevance as a homeowner

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For just over a week, my life has revolved around a huge milestone in my adult life. I bought a house! I’ve closed, cleaned, hired service people, moved, and used my electric lawn mower for the first time. It has been a whirlwind, and the weather has been perfect for all of it! Maybe I’m greedy. I could use just one more weekend of great weather so I can do some of my outdoor projects this weekend – like painting the porch rails – but it looks like my luck is about to run out.

While thinking about all I’ve done since closing and all that still needs to be done to make the house feel like my own, I’m somewhat surprised at how much the weather has played into my planning. I mean, of course it has, but this much? Here are a few examples:

Rain barrels

Did you know rain barrels are considered a fixture in real estate terms? I would have bought the house had they not already been on the property, but the fact that they were there was a bonus. Rain barrels have always been on my “wants” list for when I owned a home. Those giant drums that catch the rain runoff from your gutters can be used to water the plants in your flower beds and gardens. At the moment, mine are empty, and that is fine since I needed to move them for the power washers anyway. A full rain barrel is exceedingly heavy. My thinking was that once I stained the deck, they could be put back in place. With a decent chance for rain on Sunday, I may have to postpone the staining and put them back sooner.

Garden

Speaking of gardens, I have one now! What do I know about gardening? Not as much as I would like to. I mean there is more to having a garden than just planting seeds and waiting for veggies to pop out of the green stuff, right? I’m just kidding. I’m not quite that ignorant, but I have a lot to learn if I want to harvest some healthy goodness next year. Right now, the tomatoes are small and green, and the pepper plants are wilted and sad. Even I can tell what’s left from this summer’s growing season needs rain.

Outdoor living space

The house has a nice deck. It needs a little TLC, but that doesn’t bother me too much… until I realize the TLC requires another full weekend of sunshine. I guess that project will have to wait.

So, my garden and rain barrels need water, but the deck and other projects such as cleaning the over-stuffed gutters need more dry weather. Suddenly, I’m looking at the forecast with an entirely new perspective. I’m sure those of you reading this who have been homeowners for years are snickering a bit and thinking “welcome to the American dream.” I’m fine with it, really. It’s all part of the life I’m building for myself.

Wed-Wed QPF forecast

The Weather Prediction Center’s precipitation forecast for October 4 through the morning of October 11 shows over an inch of total rainfall is possible for our area over the next seven days.

Oh, but this is a weather blog, and not an HGTV article, right? I’m sure you’ve caught that the pattern is about to change. The area of high pressure that has dominated our weather this week will move eastward by Friday. Its movement will allow two low pressure systems to influence our forecast. One system will be moving across the Great Lakes region. The other could be named Tropical Storm Nate in the next 24 hours. It looks like Nate will move up through the Gulf of Mexico, into the Deep South, and then link up with the frontal system associated with that Great Lakes low as it crosses the Appalachians.

The result of all this atmospheric motion will be a change in the wind direction, which in turn, will bring warmer, humid air up from the Gulf of Mexico. Our dew points will increase, leading to warmer overnight lows this weekend. Our chances for rain will also increase starting late Saturday evening/overnight. Sunday will bring a good chance for showers with some thunder possible, and the weather will remain unsettled through Monday and into Tuesday.

The deck can wait. I think I will celebrate the rain along with those plants in my garden.

Weather Blog

Winter Forecasting: Indigenous Prognostications and Old Wives’ Tales

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Long before The Game of Thrones made “Winter is coming,” a hashtag, people have been looking for ways to predict how cold, snowy, wet, warm, or long an impending winter might be. As we head into fall, I thought it would be a nice break from talk of hurricanes and disasters to review a few of the more popular and interesting ones.

little bird, big snow

A little bird searches for seed under a birdfeeder in the author’s backyard on December 26, 2016 after a big snow by Raleigh’s standards.

Persimmon seeds

This one popped up on my Facebook feed, yesterday, and it’s one I had never heard of. Maybe that’s because I haven’t lived in the Ozark mountains where persimmons must be somewhat popular trees. (I have to admit, I even had to look up whether the fruit was edible.)

According to a post on Buffalo National River’s Facebook page:

Early settlers of the Ozarks would often predict winter weather using a persimmon seed. If the kernel inside the seed was shaped like a spoon, they predicted an abnormally wet and snowy winter. If it was shaped like a fork, they would expect some dry, powdery snow and a mild winter. If it was shaped like a knife, they said that icy wind would “cut” the winter air.

Based on the photo that goes with the post (follow the hyperlink to see it), the Ozarks might expect “an abnormally wet and snowy winter.” Someone, please remind me to see how that turned out next spring.

Woolly worms

North Carolina folks will be more familiar with this one because Banner Elk has an annual Woolly Worm Festival in October. According to the website allaboutworms.com, the wooly worm is a caterpillar that becomes a tiger moth. “In the American Northeast, it is believed that if the woolly worm has more brown on its body than black, it will be a fair winter. If the woolly worm has more black than brown, the winter will be harsh.”

For the record, last year’s Woolly Worm Festival winner was named Hans Solo, and according to the festival’s website, he predicted week 1 to have normal temperatures with light snow, weeks 2-4 to have below normal temperatures with accumulations of snow, weeks 5-11 to have above normal temperatures with little or no snow, and weeks 12-13 to have average temperatures with light snow.

How did the winter turn out?

Looking at Sugar Mountain Resort’s snow history for the season, there was no snow reported the first week of winter, 22 inches of snow during weeks 2-4, five inches in weeks 5-11, and none recorded during weeks 12-13. For the science-minded and curious, according to the National Weather Service’s archived data for Asheville, which is the closest NWS climate reporting station, December 2016 had below average precipitation, January had slightly above normal precipitation (by 0.72 inches), and February and March had below normal precipitation. All four months experienced above normal temperatures.

The Farmer’s Almanac’s signs of a hard winter

The Farmers’ Almanac is famous for folklore and unscientific predictions about winter. One blog post from 2008 lists “20 signs of a hard winter.” A few that I have noticed here in Wake Forest that happen to be on the list: thicker than normal corn husks, heavy and numerous fogs during August, and spiders spinning larger than usual webs and entering the house in great numbers (shudder). Of course, the only one of these that is scientifically verifiable – as opposed to being based upon memory of past encounters with web-spinning spiders and how thick corn husks seem to be when I shuck my own corn – is “heavy and numerous fogs during August.” If you drive over the Neuse River as early in the morning as I do, you may have noticed those foggy mornings, too.

The Climate Prediction Center uses real science

To contrast woolly worms and creepy arachnids, I like to look at the Climate Prediction Center’s forecast, and I like to keep in mind that 3 months in advance, I don’t expect a great deal of accuracy from it either. The CPC considers things like El Nino/La Nina, global trends, and other large scale oscillations when making long-range seasonal forecasts. The forecast for the months of December through February show above-average chances for above-normal temperatures for most of the country including North Carolina, as well as mostly equal chances for average precipitation. In plain English, that means we will probably have a warmer-than-normal winter with about the usual amount of rain and snowfall.

Truly, only time will tell how this winter stacks up.

Weather Blog

Irma – an interesting case study in forecasting

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As of this morning, Irma has weakened to a tropical storm, but don’t let the downgrade fool you. She’s still packs a punch with sustained winds up to 65 mph and heavy rains. Her tropical-storm-force winds extend outward up to 415 miles from her center, so her reach is still huge. For that reason, tropical storm warnings extend up both sides of the Florida peninsula and along the coasts of Georgia and South Carolina. Irma will be a tropical depression by tomorrow morning, and nothing more than remnants by the end of the week.

Now that the worst of the storm has subsided, I thought it would be interesting to look back at some of the forecast updates from last week. This post will be a bit graphics-heavy, but for those with short memories like mine, the graphics will be helpful.

On Tuesday, September 5, the 11 a.m. advisory graphic showed Irma passing over the northern Leeward Islands, Puerto Rico, the northern coast of Hispanolia, and possibly most of Cuba before reaching the Florida Keys. The forecast cone for 8 a.m. Sunday was actually centered on the Keys as Irma started her expected turn toward the north.

20170905 graphic

Irma’s September 5, 2017, 11 a.m. forecast track.

On Thursday, September 7, the 2 p.m. update had shifted the track slightly eastward so that by Sunday morning, Irma was making landfall near Miami. Some feared the worst as Homestead, Florida, which took the brunt of Hurricane Andrew, appeared to have become the target for Florida landfall. By that time, Irma had pasted Puerto Rico and was heading toward the Bahamas. The norther coast of Cuba was under a Tropical Storm Warning.

The 5-day track showed Irma still being a tropical storm by 8 a.m. Tuesday (tomorrow) morning, passing over the western part of the North Carolina/South Carolina border and bringing high winds, heavy rain, and possibly isolated tornadoes to much of NC.

20170907 graphic

Irma’s September 7, 2017, 2 p.m. forecast track

On Friday, September 8, the 8 a.m. forecast update, showed Irma affecting the Bahamas, northern Cuba, and central Southern Florida as a major storm. Truly, the tip of southern Florida was where the center of the cone was located. Irma was expected to take her time moving up the center of the Peninsula, into Georgia as a tropical storm, and then up to central Tennessee as a tropical depression by Wednesday morning.

20170908 graphic

Irma’s September 8, 2017, 8 a.m. forecast track

Jump forward to today, and we see Irma is a strong tropical storm moving through the panhandle of Florida, about to cross into Southern Georgia, and eventually through north-central Alabama, northeastern Mississippi, and into western Tennessee.

20170911 graphic

Irma’s September 11, 2017, 2 p.m. forecast track

If you look at this morning’s wind history map and compare it to the above maps, one fact will likely jump out at you. That forecast track from last Tuesday seems to have been the closest to her actual track and landfall overall. It’s almost uncanny!

20170911 wind history

Irma’s wind history as of the morning of September 11, 2017.

Before you rush to judgement, though, and say the National Hurricane Center should have stuck with that forecast all along, let’s think about some of the many things they consider when making these forecasts:

  1. Multiple numerical weather prediction models with multiple variations on many of them. Some are run hourly, and others run every 12 hours. Each has its own strengths and weaknesses, and each accounts for some variables in the atmosphere, but not others. It’s the forecasters’ jobs to know which tends to be the best for which type of weather.
  2. Data being added by the Air Force Hurricane Hunters’ flights through and around the storm. Their real-time information help NHC forecasters determine the actual pressure, winds, and steering currents of the storm (among other things). The information they gather is invaluable to forecasters.
  3. The way hurricanes interact with land and the ocean are very different. Both play a role in the strength of the storm. Land tends to weaken storms while warm ocean waters strengthen them.
  4. Other low and high-pressure systems in the general region (North America and the northern Atlantic) greatly influence the track of the storm. The models showed a turn toward the north, but the timing of that turn greatly depended upon the timing of the movement of a high-pressure system that was blocking that turn. Some model runs rushed it, and others slowed it down.
  5. All the things that we know we don’t know. The National Hurricane Center archives and eventually verifies its forecasts. In fact, a page of their website explains their methods for verification and shows their accuracy for track and strength for the years 2012-2016. Verification is part of the scientific method. It helps forecasters track their progress in improving their own forecasts. After all, you can’t get better at something if you don’t have a grasp of what your weaknesses and strengths are. One fact you’ll note from the NHC Official Track Error Cumulative Distribution graph on that page is that the NHC is well aware of the size in nautical miles of their forecast track error 3-5 days out. They even remind readers of the error size in their forecast advisories.

Just thinking about that fifth point, if you know your forecast track can be off by 400 miles or more for the hurricane’s possible location 5 days out, why would you stick with that forecast when it changes the next day in most of the models? In other words, if you know yesterday’s long-range forecast had a high probability for being wrong, wouldn’t you adjust it for what you’re seeing today?

Hindsight can be 20/20 as they say, but it’s unfair to Monday morning armchair quarterback a forecast track for a storm as huge as Irma. Rest assured that meteorologists are probably already looking at the above information and then some, trying to understand whether last Tuesday morning’s forecast was dead-on because it was good or if it was just an interesting coincidence.

Weather Blog

Hurricanes bring the unimaginable to life

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Last night was the 21st anniversary of Hurricane Fran hitting North Carolina. If you lived here, I probably don’t need to remind you. The devastation in Raleigh and Wake Forest made the area look like a war zone. Large oak trees were down with root balls rising into the air, blocking views of the houses they once shaded. Many people lost trees to the relentless wind and rain, and many lost homes to fallen trees. Everyone lost power, some for over a week. People had cookouts to feed their families and neighbors and in order to eat perishable food before it spoiled.

Fran's track

The track of Hurricane Fran as shown on a map courtesy of the National Weather Service.

The National Weather Service Raleigh Office published an excellent summary of Hurricane Fran’s lifespan and impacts. Within it, there is a radar loop from the time Fran came ashore on our southern beaches to the time she impacted Wake County, doing $900 million in damage to our one county alone! For some readers looking at the page, it may be the first time they’ve seen the radar images, especially since the area was without power during the storm. The maps at the bottom of the summary show a bullseye with 10 plus inches of rain over Wake County and maximum wind gusts of 50 to 90 miles per hour, depending on which side of the county you resided.

If you experienced Fran or any other tropical system like her, you have an idea of the kind of devastation a hurricane can bring. Remember those howling winds and the rain pelting your roof and windows for hours on end, the brief and eerie silence as the eye passed over, and then more wind and rain that seemed to go on forever. Now imagine living through a Category 5 storm like Hurricane Irma. This morning she hit the island of St. Maarten, and her destruction was caught on camera.

I literally couldn’t imagine winds over 120 miles per hour. I’m not talking about a gust, or a tornado that hits briefly and then dissipates. I’m talking about non-stop wind consistently beating on your structures and then add rain and storm surge – damage on top of damage. Can you imagine it? Thanks to modern technology, you don’t have to. Beach cameras in the islands are bringing the unimaginable to our electronic screens while we sit and wait and wonder if Irma will affect North Carolina.

If she does – and she likely will in some way early next week – she won’t have nearly the power she did this morning as a Category 5. That doesn’t mean we should let our guard down. We saw with Fran and Floyd and Matthew that it doesn’t take a major hurricane to do major damage even this far inland.

Our best bet is to be prepared, but don’t panic.

Weather Blog

Playing whac-a-mole with click-bait

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Over the weekend, a story went viral calling for a change in hurricane categories to include a Category 6. Meteorologists recognized it for the click-bait it was, but many non-meteorologists did not and shared it – much to our chagrin.  The story was written by a politician and published on a website that appeals to preppers and conspiracy theorists, which should be an automatic red flag to any reader with critical thinking skills. I’m not going to name the story, the website, or the writer here because I don’t want to encourage anyone to waste their time reading it.

Trying to squash stories full of misinformation and unlikely worst-case scenarios is meteorologists’ version of the game whac-a-mole. It’s frustrating, and I doubt we’ll ever truly win.

The reason this particular story was so off-base and unhelpful was simply that it was written by someone who (I can only assume) didn’t even do basic research on what a Category 5 storm is on the Saffir-Simpson Hurricane Wind Scale. I will even admit that I had to refresh my own memory this morning after seeing red when realizing how viral that post had become.

Irma map

Hurricane Irma is a Category 5 storm as of this morning, September 5, 2017.

The description of Category 5 storm winds includes the wording “157 mph or higher,” which means there is no reason to change the scale. If we do see winds higher than ever seen before, it will still be called a Category 5. If meteorologists decide to change the scale at some point in the future, they will likely shift the scale’s wind speeds similarly to the way the tornado categories changed by going from the Fujita Scale to the Enhanced-Fujita Scale. If that decision is ever made, it will be made by the expert scientists, not politicians.

Part of the reason Category 5 storms don’t usually strike the continental US while sustaining that strength is they typically hit slightly cooler waters and more wind shear after crossing the Gulf Stream and other warm ocean currents, which weakens them. Moving over land such as the islands in the Caribbean also weakens storms. Still, strong storms such as Camille and Gilbert do occasionally make landfall while maintaining status as a Category 5. It happens, but it’s rare.

Category 5 storms in general aren’t as unusual as one might think, though. One of the problems with being human is we tend to have short memories about things like storm strength.  If you look at the National Hurricane Center’s “Hurricanes in History” page, and just do a search of the term “category 5,” you’ll see just how many of those storms summarized on that page actually reached that status and then weakened before hitting the continental U.S. (7) versus how many made landfall while sustaining Category 5 status (3).

One of the false points made in the click-bait article was that Irma strengthened faster than meteorologists expected. This was untrue. Several of the models showed Irma bombing out as soon as she reached warm waters and ideal conditions. Again, this happens. We wouldn’t already have the phrase “bombing out” if it didn’t. A storm is said to “bomb out” when it strengthens rapidly, showing a large, fast drop in barometric pressure.

Another point that article claimed is that a storm of Irma’s potential strength would wipe cities off the map. The potential for that kind of devastation should go without saying for any major hurricane. Residents of North Carolina in the 1990s will tell you about the eastern N.C. town of Princeville, which was literally destroyed by Hurricane Floyd’s flooding. By the way, Floyd peaked at Category 4.

If you follow other meteorologists on social media, I’m sure you’ve seen many of them trying to squelch false weather stories, outlandish claims, worst-case doctored forecast maps, etc. I think I can speak for all of us when I say we’re frustrated with the rampant sharing of dis- and misinformation about the weather.

Before you share a story that seems too good or too bad to be true or is from a source that seems suspect, please take a moment to think critically about it, even research it if you have time. If you aren’t sure of its validity, just don’t share it. Don’t be part of the problem, please!