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


X marks the spot as tropics stay busy

NHC's Graphical Tropical Weather Outlook map showing several areas worth monitoring over the coming days

NHC’s Graphical Tropical Weather Outlook map showing several areas worth monitoring over the coming days

We are in prime time of the hurricane season and with the Atlantic Basin as warm as it is, it comes as no surprise really that there is plenty to talk about.

The NHC has several areas outlined this morning, including the remnants of TS Grace, that bear watching over the coming days.

First up, TS Henri is weak and is moving quickly now to the north. The forecast calls for a turn to the northeast as it transitions from a tropical storm in to a more spread out extra-tropical system over the far reaches of the North Atlantic. Seas will begin to subside in and around Bermuda where some beach erosion took place over the past couple of days due to the constant easterly swell that Henri was generating.

Henri could bring a period of heavy rain to parts of extreme southeast Newfoundland but the fast movement will limit the impact and its duration.

Next we have the remnants of tropical storm Grace moving towards the northern Leeward Islands. There has been a significant increase in deep convection with the system which could lead to periods of heavy rain and gusty winds as the low pressure area moves through. While there is little chance for it to become a tropical storm again, we know by now that rain alone is enough to cause major issues if too much falls at once. The forecast indicates that the remnants will track westward towards Puerto Rico over the weekend. We’ll have to watch and see what happens once the energy gets in to the southwest Atlantic or possibly the southeast Gulf of Mexico some time next week.

Off the coast of Africa is where the next large tropical wave is making its debut. The NHC is giving it a medium chance of development over the next five days and if it does in fact do so, it would be the 5th such development in the MDR or Main Development Region since late August. This is almost unheard of during strong El Nino seasons yet here we are, Danny, Erika, Fred and Grace all developed between Africa and the Lesser Antilles. This next system shows promise to become a hurricane over the open waters of the Atlantic in the coming days. As long as it remains away from land, so be it.

Finally, a small low pressure area has developed well to the southwest of the Azores Islands in the northeast Atlantic. It has only a small opportunity for development and of course wouldn’t be an issue for any land areas; something to watch but nothing to be concerned with.

To sum things up, there is plenty to keep track of but no major issues brewing in the tropics as of now. Enjoy the weekend, nice fall-like weather will be in store for much of the eastern part of the nation but then we return to the summer look and feel to things shortly, so take advantage of the cooler temps while you can! I’ll have a video discussion posted later this afternoon.

M. Sudduth 9:40 AM ET Sept 11




After Fred, probably going to be quiet for a little while

Fred was an amazing event- bringing hurricane conditions to a small portion of the Cape Verde Islands yesterday; something not seen in well over 100 years in that region.

Now Fred is weakening as it encounters cooler water and more stable environment overall. The short-lived hurricane added a few ACE points to the season total which is now near 20 for those keeping score. ACE is the seasonal accumulation of actual energy that is output by tropical storms and hurricanes. Normally we see an ACE “score” of around 104 – most predicted 40 or less for this season. We are half way there and it’s only September 1.

Wind shear map from Univ of Wisconsin showing very strong winds (blue-ish color) blasting through the tropics

Wind shear map from Univ of Wisconsin showing very strong winds (blue-ish color) blasting through the tropics

So what’s happening now that Fred is on the way out? In short, not much. Take a look at the upper level winds on the graphic. I have highlighted the strongest band of upper level winds which are literally tearing across the deep tropics right now. We are talking about several thousand miles of ocean and the atmosphere above it that is essentially shut down from a tropical development stand point. Any westward moving tropical wave will be met with strong eastward moving wind that will literally tear the system apart.

There are some signs that this could change in the coming week to ten days but don’t look for anything drastic, maybe a slight relaxation of the shear. This would come as a more favorable MJO or Madden-Julion Oscillation migrates through the Western Hemisphere as indicated by the GFS and the ECMWF models. However, it doesn’t look to be very strong and as such, I don’t see much chance for any development over the next five to seven days.

Meanwhile, the Pacific continues to put on quite a show. Hurricanes Kilo, Ignacio and Jimena all remain out over open water, far from land. The record pace of the Pacific season is not just due to the El Nino but a warm north Pacific as a whole, something we have not seen in quite a while.

TD 14-E track map from the NHC

TD 14-E track map from the NHC

In the east Pacific, TD 14-E is forecast to strengthen in to a tropical storm as it tracks generally northward. However, conditions do not appear to favor a hurricane forming out of it and even if it did, weakening is indicated later in the forecast period. I see no reason for this to be an issue for the Baja or elsewhere along the Pacific coast of Mexico.

That’s it for now. Enjoy the fairly quiet start to September. This is typically the busiest month of the season, even in El Nino years. Will we end the month without a hurricane strike along the U.S. coast? Only one way to find out!

I’ll have more tomorrow.

M. Sudduth 11:30 AM ET Sept 1


It’s mid-August, do you know where your hurricanes are?

Sea surface temperature anomalies showing the El Niño in the Pacific. Notice how much warmer the Pacific is than the Atlantic

Sea surface temperature anomalies showing the El Niño in the Pacific. Notice how much warmer the Pacific is than the Atlantic

Normally we would have had a hurricane by now in the Atlantic Basin. Normally.

This year is far from normal.

First of all, El Niño is in full swing along a vast stretch of the tropical Pacific. This abnormal warming of both the surface and subsurface waters has created all kinds of weather havoc with more to come. Luckily for those of us in the Atlantic, El Niño is typically a big bully to developing hurricanes.

Second up – wind shear and lots of it. Strong upper level winds blowing across the deep tropics, especially coming through the Caribbean, has done its job of keeping fledgling hurricanes from taking flight. This too is a common occurrence during El Niño years.

Saharan Air Layer still holding on in the tropical Atlantic

Saharan Air Layer still holding on in the tropical Atlantic

Third culprit – dry, sinking air. A lot is often made of African dust and the Saharan Air Layer but I think it sometimes gets more attention than it deserves. There have been quite a few impressive outbreaks of dry, warm air spewing off the Sahara in recent weeks and months but it is the overall pattern of dry, sinking air that has really put a lid, literally, on tropical development in the Atlantic. Any why not? With all of the warm water in the Pacific, the upward motion has been focused there while the Atlantic, though warmer than perhaps some had expected, is still out of balance and thus the non-rising nature to the atmosphere. This lack of general upward motion has been a serious impediment to development this season.

Now enter 96L in to the picture. What about its chances?

NHC 5-day Graphical Tropical Weather Outlook showing 96L and its potential development/track area

NHC 5-day Graphical Tropical Weather Outlook showing 96L and its potential development/track area

The National Hurricane Center is giving it a high chance of becoming a tropical depression sometime this week. After all, it’s mid-August, water temps are plenty warm and we have a well developed tropical wave and surface low moving across the deep tropics. It seems like it would be all systems go, right? Maybe but probably not – at least not this time.

Conditions for development are marginal right now though the water is warm, there’s no doubt about that. But warm water alone is not enough. The environmental conditions needed to produce deep, tropical convection just seems to be lacking once again in the tropical Atlantic. This was predicted very well in advance of the season by models such as the ECMWF seasonal forecast. In other words, it’s no surprise that we’re seeing such little activity. That being said, there is at least a chance that 96L makes it to become a tropical storm over the open Atlantic. If so, its name will be Danny.

Recent intensity plots for 96L

Recent intensity plots for 96L

Some of the intensity models indicate that 96L will become a tropical storm and eventually a hurricane. I just have a hard time seeing this considering the hostile environment ahead of the system. Never the less, we have something to watch now and as August comes to a close in a couple of weeks, we may have even more to watch. For now, the hurricanes have been shut out completely this season in the Atlantic and it looks to remain that way for the time being. We shall see.

Check out my video blog which will cover all of these topics and more – I’ll have it posted later this afternoon.

M. Sudduth 6:00 AM ET August 17


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