One ingredient is in place: very warm ocean temps

As we all know by now, it takes a very specific set of ingredients coming together at the right time to produce tropical cyclones – and in our case, hurricanes. Sometimes all of the pieces are seemingly there, yet nothing happens. One key element of the whole process is warm water, there is no doubt about that. Warm water, usually around 80F or higher, is what fuels hurricanes and the warmer it is, the stronger they can become.

Sea surface temperature anomalies (departure from normal) showing a very warm western Atlantic, Gulf and Caribbean Sea. Contrast this to the cooling tropical Pacific and it could make for a busy August-October for hurricanes in the Atlantic.

Sea surface temperature anomalies (departure from normal) showing a very warm western Atlantic, Gulf and Caribbean Sea. Contrast this to the cooling tropical Pacific and it could make for a busy August-October for hurricanes in the Atlantic.

This year, water temps in the western portion of the Atlantic Basin are warmer than normal in most locations. Check out the very latest anomaly map which shows the departures from normal across the region. Clearly, the Gulf of Mexico sticks out as does the western Atlantic just off the Southeast coast. Also of note, the Caribbean Sea has several areas of positive anomalies – meaning that water temperatures are above normal.

Obviously, none of this will matter unless there is a hurricane to tap in to the vast energy stored in this warmer than normal water. Right now, I see nothing in the global models to indicate that anything will be developing in the near future – all of the action is in the east Pacific right now. In fact, I have a theory that with all of the constant hurricane activity between Hawaii and Mexico, perhaps the sea surface temps will be cooled enough to create a stark contrast between the Pacific and the Gulf of Mexico/Western Caribbean. This could create more favorable conditions later in the season for that region – we will just have to wait and see about that.

For now, the warm water is in place, there’s no doubt about that. Whether or not it becomes a factor during the heart of the season, still a month away from beginning, remains to be seen. It will be something to keep an eye on for sure.

I will have more later in the week.

M. Sudduth 1:40 PM ET July 18

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It’s July – tropics are supposed to be quiet

Hurricane season climatology graph showing the slow progression towards the peak in September. The green arrow is where we are today - still a long way to go.

Hurricane season climatology graph showing the slow progression towards the peak in September. The green arrow is where we are today – still a long way to go.

I have seen a bit of an uptick in chatter on message boards and social media about how dead the Atlantic Basin is right now. In fact, there has been some talk suggesting that things are abnormally slow and that the season is destined to be quiet like the last few. While I won’t pretend to know the future, I do know the past and that can help us to understand why things are so quiet now – and why it probably won’t last.

First of all, it’s early July, not mid-September. Climatology speaks volumes and from that perspective, it is supposed to be tranquil across the Atlantic Basin right now. Take a look at the graph – it shows the season spread out over time with the peak being in September. The green arrow that I added shows where we are today. This is one of the least active periods of the hurricane season and for good reason: it has always been this way (with the exception of a few outlier years).

During this time of the year, surface pressures typically run higher than normal across the Atlantic as large outbreaks of Saharan dust and dry, stable air move off of Africa. Again, nothing unusual about this at all. It takes time for the season to evolve and get things in to alignment for the peak months ahead. Once in a while we will get a storm or hurricane to develop during what is normally an inactive period, but on average, this period of time during the season is usually tranquil.

One huge difference between this season and last is the change in SST anomalies in the Atlantic and the Pacific - very easy to spot those changes here.

One huge difference between this season and last is the change in SST anomalies in the Atlantic and the Pacific – very easy to spot those changes here.

Another aspect of this season that is different from last season is the absence of El Nino. In fact, much of the tropical Pacific, along the equatorial region, has water temps that are below normal now. While we are not quite in to La Nina conditions, the contrast between this year and last year is astounding. You can see this very clearly on the graphic I have posted here.

Notice the very warm Pacific this time last year and compare that with the Atlantic at the same time. Now we see how things have dramatically changed in just a year’s time. The result is a more favorable Atlantic Basin but it’s not ready yet. Climatology tells us that it takes time. While no one is eager to have a hurricane headed in their direction, some may be wondering why we aren’t seeing any just yet. I believe it is all a matter of time and once the pattern shifts and the pressures begin to fall across the Atlantic, we will see less dust, more convection, more active tropical wave and eventually, the hurricanes will come. Where they go is an entirely different story – I have no idea! We’ll just have to be prepared, won’t we?

Enjoy the weekend, stay cool out there and I’ll have more here on Monday.

M. Sudduth 10:40 AM ET July 8

 

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East Pacific stays busy, Atlantic quiet for now

East Pacific satellite photo showing dying tropical storm Agatha (small convective blob) along with strengthening tropical storm Blas which is forecast to become a powerful hurricane over the open Pacific

East Pacific satellite photo showing dying tropical storm Agatha (small convective blob) along with strengthening tropical storm Blas which is forecast to become a powerful hurricane over the open Pacific

It looks like we will see a parade of storms and hurricanes in the eastern Pacific over the coming days. Right now, we have TS Agatha which is weakening over cooler water and TS Blas which is about to become a hurricane. Both systems continue to remain well off the Mexican coastline and will have virtually no impact on land.

The recent burst of activity in the east Pacific can be partially attributed to a more favorable pattern overall that has allowed convection to develop and thrive. This phenomenon is called a convectively coupled Kelvin wave or CCKW. What is that you ask? It is difficult to explain but essentially it is an eastward moving wave of energy, bound by the equator to its south, that seems to enhance convection and vorticity (spin) in the atmosphere. Another way to look at it – the spark that lights the fire. Often times the passage of a CCKW will trigger the development of tropical waves as they progress across the ocean. In this case, the east Pacific took advantage of the passage and now we have two tropical cyclones and a third likely later this week. The good news is that none of the systems seem bound to affect land areas.

Will the CCKW make its way in to the western Caribbean and/or Atlantic and thus set up potential development there? So far, I am not seeing much evidence to support that. The global models all indicate generally quiet conditions over the Atlantic, Caribbean and Gulf for the next several days. This is not surprising considering that when the east Pacific is active, the Atlantic is usually not. It’s also early July and from a climatology perspective, we are not supposed to see much activity right now anyway.

Radar image showing the eye of hurricane Arthur and my location over the Oregon Inlet early in the morning of July 4, 2014

Radar image showing the eye of hurricane Arthur and my location over the Oregon Inlet early in the morning of July 4, 2014

In other news, it’s now been two years since a hurricane of any strength made landfall along the U.S. coastline. That hurricane was Arthur in the very early morning hours of July 4, 2014.

I was in the eye of the category two hurricane over the Oregon Inlet in fact where the wind was about as calm as could be for about 20 minutes. Arthur produced moderate storm surge flooding, in some cases 4 to 5 feet of it, along portions of the Outer Banks, mainly south of Oregon Inlet. The disruption to tourist season was a major issue but the area rebounded quickly and fortunately, no other hurricanes had direct influence on the Outer Banks that season.

I will cover Arthur’s anniversary and more in my video discussion which will be posted later this afternoon.

M. Sudduth 10:15 AM ET July 4

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East Pacific hurricane season about to spring to life; Atlantic remains quiet

NHC outlook map showing what is now invest area 94-E (red area) well off the coast of Mexico. The other area in yellow is not forecast to develop.

NHC outlook map showing what is now invest area 94-E (red area) well off the coast of Mexico. The other area in yellow is not forecast to develop.

It’s been a long time coming but the east Pacific is about to get its first named storm and eventually, very likely, a hurricane.

The NHC mentions an area of low pressure that is currently situated well to the south and west of Mexico. It is currently not very well organized but a combination of overall favorable atmospheric conditions should allow it to become a tropical depression over the weekend.

Current computer guidance suggests that it will continue to strengthen and become a tropical storm and eventually a hurricane over the open water of the east Pacific.

Fortunately, no matter how strong it manages to get, there are no indications from the global models that it will affect Mexico directly. There could be some impact from ocean swells generated if the system becomes a hurricane. We can worry about that later if need be. The bottom line is that the east Pacific has been very quiet up until now but this system poses no threat to land.

Meanwhile, the Atlantic Basin remains quiet although the tropical waves are getting a little more pronounced as they cross the MDR (Main Development Region). They are not likely to develop due to generally unfavorable conditions across the region which is typical for this time of year.

None of the global models are showing any significant development across the Atlantic, Caribbean or Gulf of Mexico over the coming week or so. This means the July 4th time period will be problem-free along the coast as far the tropics are concerned.

And as an FYI – Dr. Phil Klotzbach from Colorado State University issued an update to the 2016 seasonal outlook this morning. So far, no changes appear in order for his forecast of an average season overall. Conditions appear reasonably favorable for perhaps 5 more hurricanes to form with two of them becoming category three or higher. It is interesting to note that between the four named storms that already occurred this year (Alex, Bonnie, Colin and Danielle), the total ACE points generated is only 6 units. The ACE index is a way to gauge the quality, if you will, if a storm or hurricane. The stronger and longer lasting it is, the higher the ACE units generated. So while much has been made of having four named storms already, the energy output has been meek to say the least.

All in all, it looks like a run of the mill season shaping up which means we probably won’t see much until later in August and in to September and beyond. This is typical of an average season but does not preclude the chance of something developing later this month. Right now, I see nothing to worry about.

I’ll have more on the east Pacific system throughout the long weekend ahead. Stay safe if traveling – it’s a busy weekend coming up!

M. Sudduth 11:30 AM ET July 1

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No major issues in the tropics right now – just one area to monitor in NW Caribbean

Map showing location of invest area 95L over the NW Caribbean Sea

Map showing location of invest area 95L over the NW Caribbean Sea

The tropics remain quiet for the most part as we begin to approach the end of June. Only one area, tucked away in the NW Caribbean Sea, is of any concern and even it has a low chance of development.

This morning’s update from the NHC indicates that a tropical wave and a weak area of low pressure is present just off the coast from the Yucatan peninsula, over the northwest Caribbean Sea. It is rather disorganized with limited convection associated with it.

As with the precursor to what became TS Danielle, the main threat here will be periods of heavy rain for portions of Central America as the wave/low moves across over the next few days. And, as was the case with Danielle, if the low has enough warm water to work with once over the southern Bay of Campeche, there is potential for some additional development. Right now, nothing indicates any major issues arising from this system but it is something to monitor.

Computer models indicate that a track similar to Danielle would be likely which means more rain possible for eastern Mexico over the weekend. I see no reason to believe that this system would be of any concern to Texas or elsewhere along the U.S. Gulf Coast.

Meanwhile, the Pacific remains virtually shut down, quite a stark contrast to last year when several hurricanes had formed by now. This is truly remarkable and I do not see the trend ending anytime soon. Perhaps within the next 10 days something will try to get going as a strong upward motion (MJO) pulse is forecast to move through the region, helping to promote tropical convection and thus increasing the chances for development.

I will have more here tomorrow.

M. Sudduth 10:50 AM ET June 23

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