Hurricane season nears: El Nino not likely to be a factor but warm Atlantic could be

We are closing in on the 2017 Atlantic hurricane season and thus far, it look as though El Nino will not do much to limit activity. On the other hand, the tropical Atlantic has warmed up quite a bit since early spring and this might be the tipping point that gets us in to an active season once again. I cover this and more in my latest video discussion posted below:

M. Sudduth May 22, 2017

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If El Niño is coming, it will likely be too little, too late

Mid-March ENSO forecast showing a high probability of El Nino conditions setting in by the summer months.

Mid-March ENSO forecast showing a high probability of El Nino conditions setting in by the summer months. Click for full size image.

There was a lot of talk about the resurgence of El Niño just a couple of months ago and it looked as though we were in fact heading in that direction. This would have been unusual to see since we just had a substantial El Niño or warm ENSO event back in 2015.

The presence of El Niño is also a known detriment to Atlantic hurricane activity, especially in the deep tropics. As such, most of the reliable seasonal forecast agencies were calling for less activity than we saw in 2016.

So where do we stand now? As we approach mid-May, the odds of El Niño are going down. There are some mechanisms in place to get it started but so far, it’s stalling out of the gate.

Latest subsruface anomaly chart showing only limited warming overall and nothing significant at the surface of the tropical Pacific

Latest subsurface anomaly chart showing only limited warming overall and nothing significant at the surface of the tropical Pacific. Click for full size image.

Take a look at the latest subsurface anomaly chart and you’ll see what I mean. The top of the chart is the surface of the tropical Pacific while the bottom represents more than 400 meters of depth. While there is a large “blob” of positive anomalies showing up, it is no where near as substantial as what we saw in 2015. Furthermore, it is not strengthening and being reinforced by more warm water from the western Pacific. Instead, the tropical Pacific as a whole is in a neutral state – neither too warm nor too cold right now.

The latest climate models have backed off quite a bit in recent weeks with regards to warming of the tropical Pacific. Just a month ago, it appeared that we had a near 70% chance of seeing El Niño conditions by August/Sept/Oct – now that probability has dropped to 46% according to the latest update from the Climate Prediction Center. What happened? The easy answer is that spring is usually a difficult time for the climate models to resolve what will happen with the ocean/atmosphere state several months down the road. A more complicated answer lies in the fact that there are still many mysteries surrounding the evolution of ENSO or El Niño-Southern Oscillation as it is often referred to. Sometimes we get El Niño and sometimes we don’t and the reasons why are still unclear.

Mid-May climate models have backed off the chances of El Nino quite a bit.

May climate models have backed off the chances of El Nino quite a bit.

What is becoming increasingly clear, however, is the fact that for the 2017 Atlantic hurricane season, El Niño isn’t likely to be a factor. This puts a check mark in the enhancing column for seasonal activity but the absence of El Niño alone is no guarantee of a busy season. That being said, there are recent developments in the climate models for the summer months that suggest the Atlantic Basin could be more favorable than we have seen in quite some time.

As of today, much of the deep tropics between Africa and the Lesser Antilles are warmer than normal while the subtropical Atlantic has cooled dramatically. This would tend to focus lower pressures and more favorable conditions right where we’d expect it to be – the deep tropics. While this can change, it appears that we will begin the 2017 season with no El Niño and a warmer than normal tropical Atlantic. I think it is a safe bet that for those who issue seasonal forecasts, their numbers will go up in the coming weeks.

SST anomalies have gone up in the deep tropics in recent weeks, a sign of possible higher hurricane activity during the season ahead.

SST anomalies have gone up in the deep tropics in recent weeks, a sign of possible higher hurricane activity during the season ahead.

Numbers aside, it is important to note that no one can predict where whatever does form will end up, if anywhere at all. A season like 2010 had plenty of hurricane activity but not a single one crossed the U.S. coastline. On the other hand, a season like 1992 had one significant hurricane – just one. And as they say, that’s all it took. We live in very different times than we did 10-12 years ago and that is not just hyperbole, it’s true. The advent of social media, the rise of so-called “fake news” and other political distractions mean that it is literally up to you, on a very personal level, to learn all you can about your local vulnerability to hurricane impacts. We could have 2 hurricanes form this season or 12, no one knows for sure. What really matters is where they end up and if that is your backyard, you will be doing yourself and your family a favor by being ready.

I will have much more on the coming season during a special live broadcast via YouTube Live on Thursday, June 1 at 7pm ET. Until then, get ready, hurricane season is coming – just like it does every year around this time. No reason to ignore it or act like the sky is falling, we should be prepare the same year in and year out.

M. Sudduth 8:50 AM ET May 12

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Consensus growing for active hurricane season

We are now less than three weeks away from the start of the 2016 Atlantic hurricane season and already it looks to be a busy one. Before we jump to the “sky is falling” conclusion, let’s look at things objectively and put it in to some perspective that most can understand.

Subsurface anomaly chart showing the growing area of cooler than normal water mounting in the tropical Pacific

Subsurface anomaly chart showing the growing area of cooler than normal water mounting in the tropical Pacific

What we know is that the great El Nino of 2015/16 is almost certainly dying out. We can see this by looking at various data from a variety of sources. One of those is the subsurface anomaly chart that I have included here. Clearly the warm surface water is being eroded away with a vast expanse of cooler than normal water lurking across most of the tropical Pacific. This will very likely herald the arrival of La Nina conditions or an abnormal cooling of the Pacific along the equatorial region. In short, this is typically seen as a favorable sign for the development of Atlantic hurricanes. The sooner we see La Nina set in, and the stronger it is, the more influence it will have on enhancing the chances for Atlantic hurricane development once the season gets going.

In addition, we also know, again by looking at actual data, not computer model projections, that the Atlantic Basin is warming in the area between Africa and the Lesser Antilles. This is also called the MDR or Main Development Region. The irony here is that there were some indications in previous weeks that this region would actually cool abnormally; so far, it has done the opposite.

Check out the very latest NOAA/NESDIS SST anomaly map for the region. Water temps are running above normal across the entire MDR and in to the Caribbean Sea. This is a stark difference from what we saw last season although the MDR did warm some as the season progressed. Right now, the region is warmer than we have seen it since the 2013 season and this, coupled with the loss of the El Nino, should give another check mark in the column of enhanced hurricane Activity for the Atlantic.

Latest NOAA/NESDIS SST anomaly map showing a very warm tropical Atlantic

Latest NOAA/NESDIS SST anomaly map showing a very warm tropical Atlantic

Warm water alone does not make hurricanes. The atmosphere needs to cooperate as well with aspects such as moisture level and wind shear being take in to account. Right now, those parameters don’t matter too much since it’s just May. However, conditions do seem to be a little less dry in the mid levels of the atmosphere in parts of the tropical Atlantic which is yet another indication that things may be busier than we’ve seen for quite some time. Shear will drop as the summer approaches and the westerlies retreat to the north. Once we get to August, the beginning of prime time for the season, it looks like all systems go for a busy time ahead.

With all of this mounting evidence for a busy season, it comes as no surprise that several respected agencies are forecasting either an average season or slightly above average. So many different entities are making forecasts now that it’s hard to keep up. The trend however is what is interesting to me. All of them see a busier Atlantic than the past few seasons and that will seem very busy considering how relatively quiet things have been since 2012. We will get a new forecast from Dr. Phil Klotzbach and his team at CSU in early June. NOAA will release their seasonal outlook soon as well. I think it is safe to say that, at least for now, the scale has tipped in favor of the Atlantic.

None of this matters as far as who would be impacted. I need to make that very clear. Knowing that the general large scale environment favors more hurricanes is helpful, I think anyone would agree with that. You’d rather know than not, right? Just don’t get caught up in the headlines and lose sight of the fact that even a 40 mph tropical storm can ruin your entire life – or even end it. It’s all about the impact (hence why our app is called Hurricane Impact) and no forecast can tell you with any degree of certainty what impact you will face this season.

The bottom line here is that you’re going to hear a lot about the “busy hurricane season” coming up. What you won’t hear as much about is how you can process that information and make use of it. My advice is to use that info to beef up your knowledge of hurricanes and what to do if one comes your way. A busy season does not necessarily equate to one with many (or any) landfalls. It does up the chances but no one really knows by how much. That part of the equation comes down to timing and placement of the would-be hurricane within the Basin.

It’s almost time. We are ready and hope to help you to be as well.

I’ll have more here on the 15th when the east Pacific hurricane season begins.

 

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Signs of change for 2016?

After a couple of false starts in recent years, a strong El Niño finally developed and is now firmly entrenched across a good portion of the equatorial tropical Pacific.

El Nino at its peak in the tropical Pacific

El Nino at its peak in the tropical Pacific

This El Niño event has led to a substantial increase in Northern Hemisphere tropical cyclone activity, mainly in the Pacific (obviously), increased storms for parts of western North America with more to come in the weeks ahead and a fairly wet pattern overall for much of the South and Southeast U.S.

The outlook from the various groups who monitor El Niño calls for a gradual weakening of this warm event  as we move in to 2016. In fact, there is some evidence in the long range climate models that perhaps a cooling phase of what is called ENSO (El Niño Southern Ocscillation) is in store by 2017, if not sooner.

Once past the winter and the influence of the current El Niño, things begin to look very interesting for next hurricane season for the Atlantic.

One glaring consequence of this year’s El Niño was the record level of wind shear across much of the Caribbean Sea. Strong upward motion in the tropical Pacific resulted in strong wind between about 5,000 feet and 40,000 feet across the western Caribbean and extending as far east as the Lesser Antilles at times. This is what caused would-be hurricanes such as Erika to weaken and ultimately dissipate. Only a narrow band of favorable conditions existed in the deep tropics where we saw hurricanes Danny and Fred form, far away from land areas.

Outside of the extreme upper level winds, in the southwest Atlantic, there was another area of favorable conditions and the resulting hurricanes Joaquin and Kate owe their existence to that fact. Otherwise, El Niño really did help kill off the Atlantic season as far as direct impact on the United States was concerned.

2016 might not have that protection and in fact, there is a good chance of that happening, according to the latest projections from a suite of computer models.

CPC/IRI Consensus Probabilistic ENSO Forecast

CPC/IRI Consensus Probabilistic ENSO Forecast

As of the December 10th update from the CPC/IRI (Climate Prediction Center/International Research Institute), the probability of El Niño conditions holding on through March 2016 are near 100%. After that time, things change quickly.

Once we get to spring, El Niño begins to fade as cooler water moves in from the subsurface and stronger trade winds resume across the tropical Pacific. This is reflected in the projections with the probability of El Niño conditions dropping to 60% by late spring.

Moving further out in time, the various models suggest only a 20% probability of El Niño holding on by mid to late summer 2016. This has huge implications on the Atlantic hurricane season since the absence of El Niño by itself is typically a positive signal for Atlantic tropical cyclone activity.

As we know all too well, there are many other factors at play and the Atlantic Basin seems to have the most year to year variability and is subject to large errors in forecasts for seasonal activity – 2013 being a prime example. There was no El Niño that year and it appeared that conditions would be favorable for one of the busiest seasons since 2005. Other unforeseen factors set in by summer and the season was one of the most tranquil in recent memory.

SST anomaly forecast going out to July 2016. Notice the blue showing up in the tropical Pacific - that is the beginning of La Nina conditions there

SST anomaly forecast going out to July 2016. Notice the blue showing up in the tropical Pacific – that is the beginning of La Nina conditions there

While the El Niño fades, another interesting phenomenon may begin to take shape. Some of the climate models are developing a very warm tropical Atlantic next year. If this comes to pass, especially if the far northern Atlantic is cool compared to average, then it would signal yet another reason to believe that changes are ahead for Atlantic activity next season.

Much of this was reflected in Dr. Phil Klotzbach’s first outlook for the 2016 hurricane season which was released last week. The December discussion indicates a 25% chance of seeing a hyper-active season in 2016 which would be a significant change in what we’ve seen in recent years. A lot will depend on exactly how much the El Niño weakens and how warm the tropical Atlantic manages to get before August-September-October rolls around.

Trying to put this all in to perspective, it is kind of like having a the #1 recruiting class in college basketball. Your team is loaded with incoming talent, maybe a couple of seniors with terrific skills to round things out. It appears that the next basketball season is going to be spectacular for your team. They might even have a chance to win it all and be National Champions. Along the way, things can happen: a torn ACL for your star forward. Coach gets sick during tournament play. Another player goes down with a broken hand. All of a sudden, your #1 team is now losing game after game and what looked like a sure-thing season turns out to be anything but. You just never know.

Hurricane season is much the same. It really is. There can be a plethora of signals for the Atlantic Basin to be very active and yet, when all is said and done, it wasn’t and no one really knows why until after the fact. Right now we are in the equivalent of the signing period of college basketball – when the top recruits begin to choose their college. We won’t know how things pan out until much later – maybe even during the season itself. Yet, much like college ball, I see potential building for a busy 2016 in the Atlantic. However, just because something might happen, doesn’t mean that it has to happen.

I’ll post an update to this blog in mid-January. By then, we will have even more data from the various climate models and the picture of what lies ahead will become just a little bit clearer.

M. Sudduth 10:15 AM ET Dec 14

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Tropical wave in cental Atlantic a sign of what’s ahead

Tropical Weather Outlook map from the NHC showing area of interest in the central Atlantic

Tropical Weather Outlook map from the NHC showing area of interest in the central Atlantic

Not much going on in the tropics since Arthur earlier this month. This is typical for July which is usually a very quiet month in the Atlantic Basin.

In fact, we did not have any tropical waves to flare up worth mentioning until yesterday when the NHC issued an outlook for one in the central Atlantic. It rolled off of Africa a few days ago and has a low pressure area associated with it at the surface. Water temps are warm and overall, environmental conditions are generally favorable for development right now. However, this is likely only temporary as it looks as though conditions will not be so great for development as the week wears on. It’s just too early in the season yet for robust Cape Verde tropical waves to get going this far east. We’re still looking at another month or so before that happens.

The presence of this system does remind us of what could lie ahead. As I mentioned, July is usually not very active, especially in the deep tropics. Once we get in to mid to late August, conditions change and we begin to see more and more active tropical waves moving west from Africa. At that point, it will come down to upper level winds and, perhaps more importantly, instability in the atmosphere. If the mid-levels of the atmosphere are too dry with lower humidity value than usual, then the tropical waves will struggle to develop deep convection and will remain weak. On the other hand, if moisture levels are where they should be or are above average, then we would likely see a very busy August and September.

I believe that much will depend on the situation with the El Nino which was forecast to be coming on quite strong by August. As it turns out, there is barely any El Nino to talk about, especially in the central regions of the tropical Pacific. It just never made it and what warming there was has all but vanished. However, the water just west of South America, extending westward for several hundred miles, is still quite warm compared to normal. This could have just enough negative influence on the Atlantic side to help keep the peak months of August-October quieter than normal.

One thing I will be watching for is how much, if any, cooling takes place in this region of the Pacific. There are indications that we could see a considerable drop off in the surface temperatures of this area and if this happens, I suppose it could remove at least a portion of the negative influence for the Atlantic Basin. It’s just so complicated and hard to tell if one puzzle piece really makes that big of a difference considering how the other pieces fit together and interact with each other.

For me, the tropical wave that the NHC is talking about this morning is a sign that we are approaching the peak months of August-October. Thus it is a good time to remind you to be aware and prepared. Arthur was an interesting event in that it was so early in the season and it did not fall apart at landfall – instead, it continued to strengthen despite its close proximity to the North Carolina coast. If that is the way things will go this season, it won’t matter much if tropical waves develop far out in the Atlantic. What matters are the ones that would do so close to land, leaving little time to react. We’ll see how things shape up over the coming weeks but August is just around the corner and from there on, at least from a climatological perspective, the season should become more active. Time will tell just how active, that is the only certainty at this point.

I’ll have another blog post here tomorrow morning.

M. Sudduth 10:24 AM ET July 21

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