Hurricane Conference made one point very clear: it’s time to focus on the impacts, not the categories

Hurricane Isaac, 2012

Hurricane Isaac, 2012

Hurricanes are very unique in many ways. We have come to know them by name, literally, and have also become quite fixated on giving them a ranking before they ever make it to land.

This is not the case with tornadoes. Nor earthquakes. Those phenomenon are not categorized until after they occur. So what is it about hurricanes that makes us want to give them a number, 1 to 5, that somehow signifies the level of danger – or so it would seem? Why is a category one hurricane less dangerous than a category two?

Let’s look at it from the tornado angle. You never, ever hear the legendary James Spann (Birmingham, Alabama TV meteorologist) say, “Oh, this is just an EF1 tornado, nothing to worry about”. Yes, I know hurricanes and tornadoes are vastly different weather events with different impacts but the point is, when we hear “tornado!” we run for cover, right? It’s just not the same for hurricanes and the realities of the public clearly not understanding hurricane impacts have become front and center as of late. Want proof? Look at Sandy and Isaac last year.

Sandy was a huge, powerful and very dangerous hurricane over the open waters of the Atlantic. Every major news outlet and even the small-time bloggers and social media storm watchers said for days on end that Sandy would be a damaging and deadly event for a good deal of the East Coast. Yet, lives were lost and tens of billions of dollars in property damage took place as a result of this “minimal hurricane”.

As for Isaac? Look at the flooding situation in LaPlace and Braithewait, Louisiana. Those areas were hit hard by category one hurricane Isaac – just barely a hurricane. Some people said they were surprised at the amount of storm surge flooding from Isaac. Why? It was noted for more than 48 hours ahead of landfall that a dangerous storm surge was coming in association with Isaac. This was not kept secret, it was right there in the main headline of each Public Advisory from the NHC:

“…RECONNAISSANCE AIRCRAFT INDICATES ISAAC GETTING STRONGER… SIGNIFICANT STORM SURGE THREAT EXPECTED FOR THE NORTHERN GULF COAST…”

Not sure how much more direct the headline can be other than saying, “Hey, Bob at 101 Main Street, yeah, 10 feet of water is heading your way by 11am on the 30th, better get ready and make plans for evacuation, okay?” Maybe one day we’ll have something that detailed, perhaps not as sarcastic hopefully, but you get the idea. Some people, however, still do not. They do not understand what they’re up against with a looming tropical storm or hurricane. That must change, if it doesn’t, people will die needlessly and more property will be lost that could have been saved.

What is the answer? I feel that there are two angles to this: education before hand and the correct information getting out when a threat is bearing down.

As far as education, yes there needs to be more of it, starting in the schools, especially in hurricane prone areas. Teach the kids and they’ll teach mom and dad. It worked for seat belt usage and (to some extent) for drug use, so why not a natural hazard like hurricanes? Get your local NWS involved. Have them come out and talk to the kids. Invite your local TV weather guy or gal. Do something to educate these kids – they deserve it and will soak it up. I know because I have personally spoken to literally thousands of them in my career.

The other angle is critical too. When a storm or hurricane is headed for land, it is imperative that the hazards affecting land be emphasized over wind speed and category. The wind speeds reported in a hurricane are almost NEVER seen over land. Unless we get a truly intense hurricane like Andrew or Charley, the wind is not the worst enemy, it’s the surge and threat from fresh water flooding. Even tropical storms need more respect. No one would ever in their right mind say, “Well Ted, you’re going to be in a wreck today but don’t worry, it’s only a head-on collision at 40 mph instead of 60, so you’ll be less injured and the car less damaged, so don’t worry too much about it”.

We need to think of tropical cyclones as dangerous, period. No more downplaying the lower categories or tropical storms. Focus on “what can hurt me, my family and cause damage to my property?” Do that, and we can make huge strides at reducing fatalities and injuries – as well as mitigate damage.

The National Hurricane Conference that wrapped up last week in New Orleans really hit this point home for me. The director of the National Hurricane Center, Dr. Rick Knabb, spoke time and again about not focusing on the categories. It’s all about impact, pure and simple. When a tropical storm or hurricane affects land, someone is going to have a bad day, always. Who that someone is and where they live is impossible to know ahead of time, not down to street level. It may never get that good so we have to think of a tropical storm or a hurricane as a threat to our lives -every time. This does not mean panic and disarray every time a storm or hurricane heads your way. It does mean TAKE IT SERIOUSLY and do not downplay the threat based on category. Read the Hurricane Local Statements, follow people on Twitter who can provide you with quality info and intel. Know that you are facing a force of nature immensely larger than anything you can possibly fathom. Do that and you’re far more likely to survive and be in a position to recover faster.

I am very impressed at the path the NHC is taking this year and beyond. Their leadership is excellent and the staff is the best in the world at what they do. New products and enhancements to old ones will be coming out over the next few years. This will help in the understanding of what to expect but in the end, it is up to each individual who lives within the reach of tropical storms and hurricanes (this means people who live 500 miles inland) to know the enemy. As G.I. Joe says, “Knowing is half the battle!”.

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Complex situation as model duel plays out

It has been an exceptional year in terms of how two of the world’s best global models have performed. I am speaking of the American generated GFS or Global Forecast System versus the European generated/supported ECMWF or European Centre for Medium-Range Weather Forecasting. Both models are highly sophisticated and provide a vast array of products for forecasters around the globe. However, both have had their share of issues over the years when it comes to forecasting tropical cyclone events.

Let’s take a look at TS Debby back in late June. The GFS was forecasting a turn to the northeast as a trough of low pressure dug in to the eastern portion of the U.S. On the other hand, the ECWMF was forecasting a ridge to build and push Debby back to the west. Here is a paragraph from the NHC’s discussion regarding Debby on June 24:

“THE TRACK FORECAST IS EVEN MORE COMPLEX. THE GFS INSISTS ON A TRACK TOWARD THE NORTHEAST AS DEBBY BECOMES EMBEDDED WITHIN A LARGE MID-LATITUDE TROUGH. HOWEVER…THE ECMWF AND THE HWRF BUILD A RIDGE TO THE NORTH OF DEBBY AND FORECAST A WESTWARD TRACK. GIVEN THE WESTWARD TURN INHERITED FROM THE PREVIOUS FORECAST…AS WELL AS THE HISTORICAL STRONG RECORD OF THE ECMWF…THE NEW OFFICIAL FORECAST MOVES DEBBY INITIALLY A LITTLE BIT TO THE NORTHEAST TO REFLECT CURRENT TRENDS BUT THEN TURNS THE CYCLONE BACK TOWARD THE WEST OR WEST-NORTHWEST IN 24 TO 36 HOURS. A MAJORITY OF THE GFS ENSEMBLE MEMBERS NOW ARE CONSISTENT WITH THE DETERMINISTIC RUN…WHICH WAS NOT THE CASE YESTERDAY…MAKING A STRONGER CASE FOR THE EASTWARD SOLUTION. WE MUST BE READY TO MAKE A CHANGE OF THE FORECAST TRACK AT ANY TIME.”

Note the reference to the ECMWF and how it has a “historical strong record”. Well, as it turned out, the ECWMF was wrong and Debby ended up turning north in to the Florida panhandle.

Forecast for Debby showing west track towards Louisiana

Forecast for Debby showing west track towards Louisiana

Later that day, the new forecast, which was the correct forecast, shows Debby headed north in to Florida panhandle

Later that day, the new forecast, which was the correct forecast, shows Debby headed north in to Florida panhandle

Now let’s fast-forward two months to Isaac in late August. Here again we had two significant differences between the GFS and the ECMWF. The GFS wanted to take Isaac north and in to a trough after entering the Gulf of Mexico, putting a substantial threat to the Florida panhandle and even the west coast.

Meanwhile, the ECMWF showed a much farther west track towards Louisiana. Here again is a quote from the NHC discussion on Isaac from August 22:

“HOWEVER…THE ECMWF CONTINUES TO SHOW A STRONGER RIDGE…AND THUS SHOWS A MORE WESTERLY MOTION THAN THE OTHER MODELS.”

As it turned out, the ECMWF was correct in a stronger ridge and Isaac ultimately made landfall in southeast Louisiana.

So what does this have to do with the current situation with Sandy? For the first few days of the forecast period, not much. Right now, the GFS and ECMWF are pretty close to each other since the pattern is fairly straight-forward right now. Sandy is forecast to move slowly northward and bend east of north and pass over or very close to Jamaica. Both models “agree” on this.

Then, both models have Sandy passing over eastern Cuba and in to the central Bahamas by around 72 hours. It’s after this time frame that the two models part ways and have two vastly different outcomes.

The GFS basically moves Sandy slowly to the northeast and out of the Bahamas. While the ECMWF takes Sandy more north by day four but also fairly slowly.

At day five, the GFS has Sandy roughly half-way between Florida and Bermuda while the ECMWF is quite a bit back to west, near 30N and 75W.

It seems that the GFS wants to hand off Sandy in to the Atlantic due to lower heights in the middle layers of the atmosphere because of a large ocean storm, partly the remnants of Rafael. This provides and escape route for Sandy to take, like a rock gradually rolling down a slope, not too steep, but just enough to build momentum and begin rolling. Sandy is the rock heading down the gentle slope.

The ECMWF does not allow Sandy to feel the slope, so to speak, and keeps it farther back to the west, much closer to the Southeast U.S. coast. Then, all “you know what” breaks loose with that model.

By day six, a significant deep trough of low pressure digs in to the west of Sandy and causes the flow to turn more from the south out over the western Atlantic. Instead of pushing Sandy out like a broom sweeping across the floor, the trough instead scoops Sandy up and swings it back to the northwest and eventually in to New England as a powerful hybrid storm. Basically, the trough “captures” Sandy and pulls it in, not allowing it to turn east and out to sea like the GFS shows. The result is a remarkable storm for the mid-Atlantic and New England; the so-called “storm for the ages” that I alluded to yesterday.

Which solution will be right? I have no idea. I can see why both models show what they show but I also know that the GFS tends to have a bias in handing off tropical cyclones in to lower height fields more often than not. In other words, the GFS is taking the easy way out and sending Sandy in to the Atlantic. The ECMWF does not do this and instead keeps Sandy in the western Atlantic long enough for the big trough to dig in and capture it, creating a large ocean storm of epic size and strength.

Day seven of ECMWF showing powerful storm as Sandy gets drawn in to trough in the East

Day seven of ECMWF showing powerful storm as Sandy gets drawn in to trough in the East

There is a lot of talk about this situation in the weather blogosphere. Opinions about both scenarios abound and some folks simply refuse to believe such a wild scenario with the ECMWF. However, considering its track record in the long term, it has to be considered and thus, once Sandy is in the Bahamas, the story will begin to unfold as to what ultimately ends up being the true course that it will take.

In the end, one of these two powerhouse global models will end up being correct. Which one that is will have enormous implications on the weather for millions of people along the East Coast of the U.S. towards the very end of the month. Stay tuned, this has only just begun….

 

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Subtropics rule the season

Hurricane Chris set the tone for the remainder of the Atlantic hurricane season

Hurricane Chris set the tone for the remainder of the Atlantic hurricane season

It has been a rather odd hurricane season so far. I say this because most of the activity, the stronger activity anyway, has developed well outside of the usual breeding grounds of the deep tropics.

Hurricane Chris, which formed back in the latter half of June, did so at 41.1 N latitude! That is incredible for so far north so early in the season.

Next up was hurricane Ernesto, the only hurricane to form south of 20 N latitude this season out of eight total hurricanes so far. However, Ernesto struggled to become a hurricane until right before landfall, another common trait this season as we’ll see with Isaac.

Gordon became the season’s third hurricane and again, well outside of the deep tropics, attaining hurricane status at 34.0 N latitude while heading for the Azores Islands.

Then there was Isaac. Several times during Isaac’s life span it looked as though it could become a powerful hurricane. Instead, Isaac struggled with dry air and the lack of an inner core all the way in to the north-central Gulf of Mexico. One private weather firm loudly proclaimed that Isaac could be another Katrina or worse! And yet the fourth hurricane of the season only managed to reach 80 miles per hour before making landfall in Louisiana. While Isaac was a large hurricane and caused significant flooding from surge and fresh water flooding, it was not a very convectively active hurricane with a well defined inner core. This kept the winds at flight level that were being measured by recon from reaching the surface. Fortunately for residents of the central Gulf Coast, Isaac was only a fraction of the intensity that we all know it could have been had environmental conditions been more favorable.

It took all the way until hurricane Kirk on August 30 to finally get a category two hurricane. And of course, this happened while Kirk was well out of the deep tropics, affecting only shipping interests.

Leslie also had promise to become a large and intense Atlantic hurricane but it too fell far short of that potential and spared Bermuda with only passing tropical storm conditions. Stronger winds and more pronounced effects were felt in Newfoundland but even here conditions were not as bad as what could have been experienced had Leslie been a much stronger hurricane.

Michael is the season’s only category three hurricane so far and guess what? It made it to this intensity at 29.6 N latitude while out over the open central Atlantic over water temps of about 80 to 81 degrees. That’s it. Just enough to get the small hurricane to really ramp up – and it maintained a strong eye feature for several days. Luckily, Michael was far from land and only padded the ACE index score for the season.

We are still tracking Nadine which has been on the map since the 11th of this month. Nadine became the season’s eighth hurricane on the 14th at 30 N latitude. This is remarkable and a sign that something is definitely “wrong” in the deep tropics this year.

I have heard everything from El Nino to mid-level dry air being responsible for the lack of intense cyclones in the deep tropics. I am sure researchers such as Dr. Philip Klotzbach at Colorado State University will be looking in to the source of this unusual pattern and I look forward to learning more about it myself at next year’s National Hurricane Conference in New Orleans. The obvious benefit here has been a substantial reduction in damage resulting from less intense hurricanes impacting land. What if Ernesto had become a 140 mph cat-4 at landfall along the Yucatan? What if Isaac had become another Katrina and brought 30 feet of surge instead of 12? We know the answers….it would have been horrible. Been there, done that. I am sure no one is complaining about the feeble nature to this season’s hurricanes. I hope too that people are curious as to why? Why would conditions be so hostile in the deep tropics? What was the root cause if it can be pin-pointed down to something that simple? Will this pattern continue for the next several seasons? While we can be thankful for the lack-luster performance of this year’s hurricanes thus far, I think understanding the mechanics of such good fortune (it’s relative, I know, as plenty of people are still cleaning up after Isaac) is important in case we see the reverse take place next season or next month for that matter.

In any case, it all boils down to this: the tropics have been strange this season and strange has meant fairly benign events for us to deal with. So far, it looks to stay that way for the next week at least. Although, once again, we will be looking for possible storm development out in the open central Atlantic, well north of the deep tropics which seem to be closed for repairs….

I’ll have more tomorrow.

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As Bermuda readies for Leslie, it looks like weak development possible in the northern Gulf of Mexico

Latest ECMWF Model Showing Leslie Very Close to Bermuda

Latest ECMWF Model Showing Leslie Very Close to Bermuda

Leslie is gradually getting better organized and will be a hurricane sooner rather than later. I think it is then only a question of how strong it will become as it moves very close to, or right over, Bermuda this weekend.

I am sure folks there are preparing which is prudent since the wind field extends out so far with the storm. This means that tropical storm conditions will arrive on the island well ahead of the center. While Leslie is forecast to pick up its forward speed, it will not be racing past Bermuda, prolonging the effects.

As was the case with Isaac, the key to Leslie’s future intensity will more than likely be related to how well it develops an inner core structure. Large tropical cyclones typically take longer to tighten up produce a well defined inner core with a ring of convection surrounding the eye. The sooner Leslie is able to accomplish this, the stronger it is likely to become as it passes Bermuda.

This will also have a significant impact on me since I am going to Bermuda tomorrow.

My plan is to take one of my large hardened cases full of weather equipment and other gear that I will set up somewhere on Bermuda to (hopefully) stream live data and video back to our servers and our app.

I will also be working with KittyCode, LLC who is the developer of the hugely popular Hurricane and Hurricane HD set of apps for iOS devices. Both of our sets of apps will contain as many video blog updates as I can put out. Of course, Hurricane and Hurricane HD offer excellent tracking maps and other tools to keep up with the latest on Leslie and other goings on in the tropics. Get Hurricane from the App Store here.

HurricaneTrack for iPhone Tower 1 Screen Shot from Isaac

HurricaneTrack for iPhone Tower 1 Screen Shot from Isaac

As I mentioned, one of my objectives is to set up a complete “wind tower” on the island to capture wind and pressure data every 60 seconds, along with a web cam image, and send this data to our app, HurricaneTrack. I will ONLY be taking one set of gear, that is all that is feasible considering that I am flying it all out there on a passenger jet. The data will feed in to Tower 1 in our app, as seen on the screen shot example from our Isaac field work last week. If all goes well, users of our app will be able to monitor nearly real time weather conditions, along with a web cam image, as Leslie moves through the area.

I will post more about my plans, where I hope to set up, etc. in an update later this afternoon.

Besides Leslie, we are tracking TS Michael but it is of no concern to land areas and will never be.

In the Gulf of Mexico, there is a complex of disturbed weather, perhaps some remnant energy from Isaac that has drifted back south, that could develop some in the coming days. Fortunately, the conditions in the area are not too favorable right now so any development will be limited. However, another round of squally weather is possible for portions of the north and central Gulf Coast region as the disturbance moves southward.

I’ll have much more here later today and will post the daily video blog to our app this afternoon as well. We recently had an update to the app, so if you own it, update it now! We have some GREAT improvements that will prove very helpful going forward.

 

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Leslie heading towards Bermuda and so will I

The latest from the NHC is more of the same for Leslie. It is a large storm, expected to get larger and get stronger at the same time. It is also forecast to pass very close to Bermuda this weekend but the effects will be there much sooner. Waves, generated by the enormous wind field of Leslie, will pound the island, one set at a time. These waves will just get bigger in time as the storm grows in size and intensity over the warm Atlantic waters. Bermuda could be in for a very rough weekend.

As such, I am going to fly to Bermuda and be on site for what ever Leslie brings. I will have a full update as to my plans and how I intend to cover the effects from Bermuda in tomorrow morning’s update.

Elsewhere in the tropics, Michael is of no concern to land as we also watch some left-over energy from Isaac that is trying to work its way back in to the northern Gulf of Mexico. There is a chance that this piece of energy will in fact develop some but conditions do not seem very favorable there right now. Anything that does pop up over the Gulf will be fairly weak and should move back over land quickly. We’ll watch it in case something bizarre happens but honestly, it looks like more of a rain maker with some squalls than anything serious.

As I said, I’ll have more here in the morning regarding Leslie and my plans to cover its impact on Bermuda.

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