Pre-June development more of an interesting feature than anything serious

Latest sea surface temps off the Southeast coast. The red circle indicates the area of likely development of the low pressure area this week. Note that SSTs are just warm enough, 26C, in a narrow area north of the Bahamas

Latest sea surface temps off the Southeast coast. The red circle indicates the area of likely development of the low pressure area this week. Note that SSTs are just warm enough, 26C, in a narrow area north of the Bahamas

Here we are again just a few weeks out from the Atlantic hurricane season beginning and we have something to watch in the waters off the Southeast coast.

The National Hurricane Center has outlined an area of interest associated with a remnant frontal system that has managed to park itself over fairly warm water (for this time of year). The atmosphere and ocean could work together to spawn a semi-tropical storm system later this week. Before anyone gets too worked up about it, let’s look at some facts.

First of all, it is May. We typically don’t see much tropical or sub-tropical activity during the month of May. However, of all the off-season months that we do get development, May is the most active. In fact, it is active enough, around two dozen or so developments over the past 100+ years, that I am not sure why the hurricane season doesn’t officially begin in May. That’s a story for another day perhaps.

This time of year, water temperatures are warming but are not typically warm enough to allow for the deep moisture content needed to support a tropical storm or hurricane. On the other hand, the southwest Atlantic is running a bit above normal right now with the 26C line (79.5F) extending northward out of the Bahamas just off the Southeast coast. This region of marginal water temp threshold is narrow and limited. It is surrounded by much cooler water temps, mid-70s or so. This gives us reason to believe that what ever tries to develop will have very limited conditions to work with.

The other aspect of this potential development, as noted in the NHC’s Tropical Weather Outlook (actually they issued a special version of it since it’s not officially hurricane season yet), is that the low pressure area that is forecast to develop is non-tropical in origin. This means it lacks the true deep warm-core structure that we see in say a tropical wave origin storm or hurricane. Take Gonzalo last October, its birth can be traced back to a tropical wave, full of heat and moisture, that emerged from Africa. The low pressure that is likely to spin up off the Southeast coast will come from a non-tropical environment off of an old frontal boundary. While this is often an excellent genesis point for tropical storms and hurricanes to grow from, it usually takes longer for them to acquire full tropical characteristics. This simply means that we are likely going to see a very shallow, limited convection based storm system develop by mid-week.

As far as impacts go, a storm over the ocean is always a concern for boaters and beach interests. An increase in swells, rough surf and winds along the coast from northern Florida up through the Carolinas is likely later in the week. Think of it as a kind of hybrid storm, not fully what we would look for during the height of the hurricane season. Thus, the bottom line here is that while it’s possible we’ll have something interesting to talk about this week, the effects will be confined to the coast and just inland and shouldn’t amount to more than passing rain showers, breezy conditions and rough surf.

One note about this: the North Carolina Outer Banks took quite a beating from a departing ocean storm late last week. Some beaches sustained heavy erosion and can ill-afford any additional aggravation right now. Hopefully this potential storm system will not meander far enough north to rough up the area any more than has already taken place. That being said, interests along the Outer Banks in the usual flood prone areas should pay close attention to what happens with this low pressure area. It’s been a rough few years, dating back to Irene in 2011. Since then, storm after storm has lashed the region and even weak systems add more to the problem.

I’ll have more here on this developing system throughout the week ahead. I’ll also be posting a video blog to our app, Hurricane Impact, as well as to our partner app, Hurricane Pro and HD, later today. It’s that time of year again, well, almost anyway…

M. Sudduth 9:10 AM ET May 4



El Niño not likely to be a factor for 2015 Atlantic hurricane season

Even though it is January, there are clues that we can look for when trying to figure out how busy the upcoming Atlantic hurricane season may be. One of those clues is the state of the El Niño.

As we know, El Niño or the abnormal warming of the tropical Pacific, tends to suppress Atlantic hurricane activity due to a number of factors. For a good deal of 2014, it looked as though a rather substantial El Niño event was going to unfold – it failed to do so. However, the tropical Pacific did warm quite a bit and in fact, most of the warmest water on the globe was found in the Pacific during last year’s hurricane season. This is a big reason why the east Pacific was so very busy and the Atlantic was not.

As of early January, the tropical Pacific was only slightly warmer than usual with a noticeable decline in sea surface temperatures in the east Pacific, just west of Central America. In fact, as far as I can tell, we are not even in an official El Niño right now as the thresholds have not been met. This is not surprising if we look at some other aspects of a traditional El Niño event.

One of those aspects is the SOI or Southern Oscillation Index. Typically the more negative it is, the more likely we are to see El Niño conditions prevail in the atmosphere AND in the oceans. What’s the trend over the past 90 days been? A slow and steady rise in the SOI. As the chart shows, October was -8.2, November was -8.0 and December was -7.6 with the current daily value showing +4.4. What does this mean? In short, it means that the pressure pattern is such that the trade winds are not all that weak across the tropical Pacific and thus the El Niño is being held back if not stopped completely.

Latest SOI chart from the Australian BOM

Latest SOI chart from the Australian BOM (click to view full size)

More evidence of the collapse of the El Niño can be seen via the temperature depth anomaly chart from the Climate Prediction Center. This shows us what the temperature profile is of the tropical Pacific from the surface down several hundred meters. Clearly you can see the loss of the warm pool as the animation progresses over the past several weeks. In fact, cooler anomalies are showing up in the eastern Pacific at a depth of around 110-150 meters. Unless more warm water begins to migrate eastward (from left to right on the chart) then the warming of the tropical Pacific will be very slow if not stopped entirely.

Equatorial Pacific Temperature Depth Anomaly Animation

Equatorial Pacific Temperature Depth Anomaly Animation (click to view full size)

So what does this all mean as far as impact on the 2015 hurricane season? While it’s too early to be confident about the demise of the El Niño, the most recent forecasts indicate that the odds of neutral conditions are beginning to outweigh El Niño as we get in to the Atlantic hurricane season which begins in June. This is very important because a cooler tropical Pacific would likely mean less upward motion in that region compared to what we saw in 2014 and this could lead to a better chance for Atlantic development, even if only a little. Remember, 2014 was not too far off from being an average season and so any increase in activity this year would seem to most people as being quite busy, especially considering how slack things have appeared to be since 2012.

Early January 2015 forecast for ENSO state - notice how the green (neutral) outweighs the red (El Nino) beginning as soon as the Feb/Mar/April time frame

Early January 2015 forecast for ENSO state – notice how the green (neutral) outweighs the red (El Nino) beginning as soon as the Feb/Mar/April time frame (click for full size image)

There are many other factors to consider as we enter the 2015 Atlantic hurricane season but the state of the ENSO is a big one and thus far, it appears that it will not be much of a negative influence. Obviously, the climate models can and do make gross miscalculations and we could end up with a raging warm episode by late summer. However, with other signals leaning in the direction of a non-El Nino event shaping up, I tend to think that the forecast will be pretty accurate and that we will not have an El Nino during the 2015 hurricane season. We shall see…

I will post an update to this information in early April, right before the National Tropical Weather Conference which is being held in South Padre Island again this year. By then, we’ll be within 90 days of the hurricane season getting started. I’ll have other topics posted before April of course but that’s the next logical time to take a look at the ENSO state again. Until next time, stay warm!

M. Sudduth 9:26 AM ET Jan 14


How’s that El Niño coming along?

Remember back in the spring when it looked like we might have a super-jacked-up El Niño? Well, that didn’t work out as some had thought, or hoped, but it does finally look as though El Niño is upon us.

Warm tropical Pacific, as seen by the orange and red plume spreading west from South America, indicates El Nino is all but here.

Warm tropical Pacific, as seen by the orange and red plume spreading west from South America, indicates El Nino is all but here.

First of all, what exactly is an El Niño? In short, it is an abnormal warming of the tropical Pacific, roughly near the Equator. As trade winds weaken, or sometimes even reverse, warmer water is able to establish itself in a band stretching from South America westward for more than two thousand miles in to the tropical Pacific. The result is often a tumultuous set of weather patterns that are thrown in to disarray due to the warmer than normal area of water.

For the Atlantic Basin hurricane season, El Niño usually equates to fewer and less intense hurricanes. It looks as though the growing warm event did not have much impact on the 2014 season directly although some of the atmospheric conditions that were present can be linked to El Niño-like patterns. An example would be the abnormally high upper level wind shear across the Caribbean and most of the tropical Atlantic this season. That is typical of El Niño despite the fact that we were not technically experiencing El Niño conditions for most of the season. In any case, it looks as though the real deal is coming on now and will be with us for the next several months at least.

Current ENSO forecast from CPC/IRI - 11/20/14

Current ENSO forecast from CPC/IRI – 11/20/14

According to the latest updates coming out of various meteorological agencies around the world, we are very close to officially having an El Niño event take place. Typically sea surface temperatures across a certain region of the Pacific need to exceed .50 degrees Celsius above the norm for an El Niño to be declared. This also needs to span a specific amount of time, not just a few days or weeks. The latest calculation from the Climate Prediction Center indicates a sea surface temperature anomaly of .80 degrees Celsius, .30 above the minimal threshold. It won’t be long now and the 2014/15 El Niño will be official.

Aside from the usual fun and games that come with El Niño for winter and spring in the Northern Hemisphere, I like to look and see what the outlook is for the coming hurricane season. It is not typical for an El Niño to last for more than a year, it usually peaks in the early spring once the onset is official and slowly fades out during the summer and fall.

So far, it looks like we will see El Niño conditions prevail through at least the next three to six months. Computer model forecasts for El Niño are notoriously bad for long lead times. After all, many were calling for anomalies exceeding 2.0 degrees Celsius by now which would be an exceptionally strong event. Obviously we are nowhere near that mark and the models that were predicting such drastic increases in ocean temperatures were flat out wrong.

One aspect of this El Niño event that I am watching closely is how well it performs at seeding the tropics with more moisture. I believe that the cooler than average Pacific over the past several years, until this year really, has helped to dry out the tropics somewhat. This might explain to some degree why the Atlantic Basin has been fairly inactive hurricane-wise after the busy 2012 season. Now that El Niño is coming on, more moisture will be fed in to the tropical atmosphere over thousands of miles which should, in turn, spread around the globe, increasing moisture and thus vertical instability in the tropics. We saw this already with the very busy east Pacific hurricane season. It is my theory that El Niño may help to jump-start tropical cyclone activity world-wide starting in 2015. This may be especially true if in fact the warm event fades as it should do starting in the spring and early summer. We will be left with added moisture in the deep tropics combined with gradually cooling tropical Pacific waters. The result, in my opinion, should be an increase in Atlantic hurricanes beginning in 2015, probably spanning a few years after. We shall see. Even if 2015’s hurricane season is more busy than the past two, it won’t necessarily mean that I was correct. I just think that the simple fact that cool water does not lead to as much evaporation and thus moisture in the atmosphere helps to explain, even if only a little, why the global numbers of tropical cyclones have been down in recent years.

For now, El Niño seems almost a certainty. How strong the event is and how long it lasts will certainly shape not only the winter and spring weather patterns but also next year’s Atlantic hurricane season. It is just one piece of the puzzle and it’s a fairly large one at that.

For more in-depth information on the latest thinking from the International Research Institute, check out this link: IRI Technical ENSO Update Published: November 20, 2014


A look back at the 2014 Atlantic hurricane season

2014 Atlantic hurricane season map

2014 Atlantic hurricane season map

Now that Arctic air has made its way in to a good deal of the Lower 48, the Atlantic hurricane season is effectively over – at least from the threat of landfall along the U.S. coastline. Technically we have two weeks left in the season but at this point, it won’t matter, the United States has escaped another season without even the threat of a major hurricane hitting.

The season was forecast to be below the long-term average and that is exactly what happened, for the most part.

We will likely end up with a total of eight named storms, six of which became hurricanes. Two out of the six hurricanes made it to category three or higher with one of those, Gonzalo, making it to category four.

While we fell short of the average number of named storms (usually we see 10 in a year) the numbers of hurricanes and major hurricanes is pretty much on par with what is expected in a typical season. All in all, the 2014 Atlantic hurricane season was fairly close to average in terms of hurricanes but the best measurement, in my opinion, the ACE index, fell short once again.

ACE or Accumulated Cyclone Energy is a better way to quantify a hurricane season. Sure, we could have 15 named storms with 8 hurricanes forming. Many people would say that was a busy season. If we look deeper, how strong were those named storms? How long did they last? Were the hurricanes short-lived too? All of this matters in what we call the ACE index which measures the energy that is output from tropical cyclones. An average season typically sees an ACE score of around 100 or so. This year, it was roughly 65 which is considerably below the average. So, looking at the season from the ACE perspective, it was quite a bit below normal and this is what was forecast by most reliable agencies who produce seasonal hurricane forecasts.

As far as impact goes, which is what really matters when all is said and done, there was very little overall for the United States.

Early in the season, hurricane Arthur made landfall in extreme eastern North Carolina, mainly affecting the Outer Banks. Arthur attained category two intensity and passed over the Pamlico Sound before heading out in to the Atlantic. Storm surge related damage south of Oregon Inlet was moderate in some places, especially around Rodanthe where at least 4 feet of water accumulated on the back side of Arthur. The loss of holiday income over the traditionally busy 4th of July period was certainly a problem but the area rebounded quickly, allowing vacationers back in within a couple of days.

Arthur went on to bring flash flooding and widespread power outages to parts of New England before making landfall again in Nova Scotia as an extra-tropical storm. It is interesting to note that Arthur was regarded by many to be the worst storm since Juan in 2003. More than 300,000 people were without power and for some, it took more than 10 days to restore the grid. This just goes to show that it only takes one event, one storm, to make a season memorable.

No other Atlantic hurricanes threatened the United States this season. However, there were indirect effects such as high surf, rip currents, etc. from Bertha and Cristobal which passed between Cape Hatteras and Bermuda. Other than that, no other hurricanes passed anywhere near the coast of the United States and none were observed in the Gulf of Mexico. Overall, the impact to the U.S. was extremely low in 2014 bringing the extended period between major hurricane landfalls to well over nine years. It is also worth noting that Florida alone has not had a hurricane of any intensity strike the state since October of 2005. This is simply an incredible statistic and one that may well have its own issues down the road when the time comes that hurricanes once again impact the Sunshine State.

Bermuda was the unlikely recipient of two direct hits from tropical cyclones this season. Fay and Gonzalo both passed right over the island causing power outages and some damage to buildings. The disruption to the economy due to loss of tourism dollars will take some time to tally up but for the most part, Bermuda fared very well considering the impact from two systems less than a week apart.

I had two Atlantic hurricane field missions this season: Arthur and Gonzalo. Both resulted in excellent ground data and the deployment of special camera systems that were placed out in each hurricane to record the effects. I will have a separate blog post about Arthur and Gonzalo on November 30 and will have plenty of data, pictures and video to share then.

The east Pacific hurricane season was exceptionally busy and produced a few hurricanes that impacted the Baja peninsula and Mexico with either direct hits or left over moisture. Two of these events, Norbert and Odile, provided an opportunity for me to travel to the Southwest where flooding was a big concern due to the remnants of these two hurricanes making their way north in to the region. I have always wanted to study the impacts of tropical cyclones on the Desert Southwest and this year, I had that chance. I will go over what I learned on my November 30 blog post. Needless to say, it was quite interesting to see the interaction between tropical moisture from a dying hurricane on the landscape of the Southwest.

Unless something develops over the next two weeks, the 2014 Atlantic hurricane season is done. While it was not a busy season, it was markedly more busy than 2013. In fact, the ACE index was almost twice as high as that of 2013. These two years of low overall activity have been great for coastal dwellers but we know that it cannot last. While I have no idea what 2015 will bring, I do think that there are signs that it will be busier than these past two seasons were. I will leave it to the seasonal forecast experts to make the call when the time comes but do not be surprised if this time next year, I am writing about a memorable 2015 season.

I will have another blog post on November 30 that will review the field missions that I undertook this past season. I will also have an exciting announcement regarding a special project that I am working on. Until then, travel safe if you’re headed somewhere special for Thanksgiving. I’ll have more here on November 30.

M. Sudduth 9:20 AM ET Nov 14


When there used to be hurricanes

Radar image of hurricane Wilma at landfall in SW Florida nine years ago tomorrow

Radar image of hurricane Wilma at landfall in SW Florida nine years ago tomorrow

Nine years ago right now, hurricane Wilma was on the move, headed for the southwest coast of Florida after pummeling the northeast Yucatan peninsula.

I was working with my team to finish up the placement of three unmanned camera systems, the first year of that project. We were ready, Wilma came, Wilma went. Millions lost power, stood in long lines waiting for ice, food, water, gasoline. It was as if the lessons from 2004 and the deadly hurricanes of 2005 hadn’t sunk in for people in south Florida. Some were prepared, most were not. Wilma ended up on the top five costliest hurricanes list and earned its place in hurricane history.

That was the last time any hurricane, no matter the category, made landfall in south Florida or anywhere else in Florida. Not a single one since 2005.

Let’s put it in to terms that most people these days can easily understand, especially considering the state of the Internet and social media.

When Wilma made landfall on October 24, 2005, Facebook was not yet open to the public (ages 13 or older with a valid email address). If there was Facebook for everyone, as there is now, you would not have been able to post a status update about your Wilma experience using an iPhone – it had not been invented yet.

What about posting 140 characters to Twitter about your harrowing encounter? You’d have to wait until late March, 2006 to do that.

When Wilma struck, there was no social network like we have today, not even close.

Children who were in 5th grade that day are now juniors if they chose to go to college.

Children who were born in Florida and have remained in Florida since Wilma have no experience with hurricanes what so ever. An entire generation is growing up without the fear, anxiety or any sense of what it is like to endure the greatest storm on earth. I worry, is this good?

We know that hurricanes are not extinct, they’re just not hitting the United States and in particular, Florida, with any regularity right now. We’ve had busy seasons – lest we forget two short years ago the legendary Sandy had its humble beginnings down in the Caribbean Sea. The hurricanes are there, they’re just not here.

I am not going to spend a lot of time on the “why” part of this issue. A lot of it is pure luck with the steering patterns that we’ve had. It also has to do with the overall numbers of hurricanes that have formed in recent years. The less of them there are, the less we have to worry – generally speaking.

This is not just a Florida issue. The lack of major hurricanes hitting the United States also stands at nine years now. We can certainly make the argument about what classifies as major. Look at Ike in 2008 or Sandy two years ago. Those were top five hurricanes in terms of dollar amounts, major events from an economic perspective. Therein lies the problem. If Ike and Sandy were not meteorological major hurricanes and caused that much damage, then we are going to be in for a world of hurt when a truly intense, large hurricane crosses the coast at the wrong location.

I know, you’ve heard all of this before. One day….blah, blah, blah. I assure you, the problem will be so big that it will overwhelm the state that it happens to and possibly tax the nation’s ability to deal with it on many levels. Why such a bold statement?

Consider this…

No major hurricanes anywhere in the United States in over nine years. That’s a long time for real estate to grow, both residential and commercial. Even with the slow-down during the recession/real estate bubble burst, there is still plenty of construction going on along the coast. People love the coast, always have, always will. The bait is out there, waiting for a hurricane to bite.

Coastal population has grown as well. I’ve read that some estimates indicate over 1 million people have moved to Florida since 2005. I wonder, how many of those folks have any idea of what it’s like to be on your own for two weeks? No food, no water, no services of any kind. It’s not pleasant.

I worry about emergency management and the ability of a community all the way up to the state level having the ability to respond to a major hurricane disaster. You can write up the best plans and attend countless conferences but until the experience hits you in the face and it’s real life, you cannot fathom what it’s like. I have friends in emergency management and even on the best of days, it is an utter nightmare to deal with the process of prepping for and then surviving a major hurricane. Add to the mix the fun and games of politics and you have a recipe for what amounts to leaving the people to fend for themselves. For the sake of the American people, local and state governments need to be ready to buckle down, work together, throw political gain out the window and get the job done. We’ll see, experience tells me that it won’t be that easy.

I worry most about the people. For the most part, people as a whole are not good at dealing with a sudden and catastrophic shock to the system. They eventually bounce back but the onset is often ugly and makes for interesting cover pictures on Time magazine.

There is nothing that I can do or say that can adequately prepare anyone for the nightmare of dealing with a devastating hurricane. Even a run of the mill hurricane can cause grief even if it’s just your house that was impacted by a falling tree of flooding from a nearby stream.

I have been in at least 25 hurricanes myself, most of them on purpose. Many of those experiences were not severe, more of a nuisance than an epic disaster. If every hurricane that hit was on the caliber of Katrina, no one would dare live at the coast. The fact is, most seasons go by without even a bother from the tropics, let alone a life-changing hurricane experience. It is difficult to convince people to take precautions against something that seems more like legendary stories than a real threat. It’s a tough balance between enjoying the lull and and at least keeping an open mind about what could happen.

I don’t want to scare people when it comes to hurricanes. They are to be respected, not feared. We fear what we don’t understand and it’s up to everyone who lives along the coast to develop at least some understanding of what hurricanes are all about. We’ve been given a gift of sorts these past nine years, especially in Florida. I just hope that gift was not Pandora’s Box.

M. Sudduth 1:00 PM ET Oct 23