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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Two storms in east Pacific – one forecast to become major hurricane

NHC map showing the positions of tropical storms Agatha (left) and Blas (right). Boh systems are forecast to remain well off the coast of Mexico.

NHC map showing the positions of tropical storms Agatha (left) and Blas (right). Boh systems are forecast to remain well off the coast of Mexico.

And just like that, we now have two tropical storms in the east Pacific. After a very quiet start to the season in that region, things have become quite busy as of late.

First up is tropical storm Agatha, situated about 1000 miles WSW of the Baja peninsula of Mexico. There’s not much to say about Agatha as it is forecast to weaken over cooler water during the next few days and obviously will not be a problem for land.

Next we have tropical storm Blas, also well offshore of the Mexican coastline. Top winds are 60 mph and Blas is forecast to reach hurricane intensity by tomorrow. After that time, conditions appear favorable for Blas to continue to grow in to a major hurricane with winds of at least 120 mph. Fortunately, the steering currents are such that no matter how strong it gets, it won’t affect land either. There could be some additional ocean swells generated by the hurricane, especially if it gets stronger than forecast. Outside of that, neither system will pose any threat to Mexico.

In the Atlantic Basin, sinking air and a fairly dominant Saharan Air Layer (SAL) are keeping things quiet for the time being. This is quite typical for July when surface pressures are generally high and these SAL outbreaks are common. I do not see anything in the global models to suggest development over the next five to seven days.

Enjoy the celebrations this weekend and tomorrow! Be safe out there – especially if traveling. I’ll have more here tomorrow afternoon.

M. Sudduth 12:30 PM July 3

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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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Bonnie leaving, now we turn attention to the Gulf of Mexico

Tropical depression Bonnie well off the NC coast this morning, finally moving away

Tropical depression Bonnie well off the NC coast this morning, finally moving away

After hanging around the Carolina coast for several days, the year’s second named storm is finally moving on. Tropical depression Bonnie is far enough off the North Carolina coast to finally have taken the rain with it. This trend will continue and eventually, the system will become absorbed within a larger weather pattern and that will be that – no more issues from Bonnie.

In the east Pacific, invest area 91-E is struggling a bit as of late with limited convection associated with it. As such, the NHC has lowered the chance for further development to 60% over the next five days. The system remains well to the southwest of Mexico and there are no indications that it will be turning back towards land even if it does manage to develop.

Now we turn our attention to the Gulf of Mexico where it is possible that we will have to deal with a broad low pressure area that is forecast to take shape over the coming days.

Computer models are in generally good agreement that energy arriving from the Caribbean Sea will gradually consolidate around the Yucatan peninsula this weekend, eventually making its way in to the southern Gulf of Mexico where it could become a tropical storm.

GFS computer model output showing weak low pressure in the Gulf of Mexico early next week. Notice how almost all of the "heavy weather" is located on the east side of the low, a sign of a generally disogranied, sheared system

GFS computer model output showing weak low pressure in the Gulf of Mexico early next week. Notice how almost all of the “heavy weather” is located on the east side of the low, a sign of a generally disorganized, sheared system

Before folks get too worried about this, let me say that this is not something that appears to be a big wind and surge issue, if it forms at all. What does concern me is the chance for heavy rain for parts of the Florida peninsula next week. As we have seen in Texas with the continued bombardment of rain there, freshwater flooding is a big deal, even coming from so-called “weak” or “lopsided” tropical storms. Even though nothing like that has affected Texas so far this year, rain is rain and the resulting flooding can be devastating and dangerous.

Taking a look at the latest GFS computer model, we can clearly see the overall disorganized look to this potential system at around the 96 hour mark. The low pressure center hangs back over the Gulf while most of the rain and any wind would be located on the east side. This is very typical of June tropical storms due to the fact that upper level winds are still strong across the region, pushing the system faster than it can line up vertically and become better organized, such as what we would see in a hurricane. In this case, even though water temperatures are warm enough for a hurricane, the pattern does not look anywhere near conducive enough for that to take place.

Right now, the NHC is giving the future disturbance a 50% chance of developing. We’ll see if this goes up over the coming days, which I suspect it might. However, what could end up happening is that we just see a broad, strung out low pressure area develop, almost like a frontal wave instead of a true tropical storm, and head towards Florida with plenty of rain.

Elsewhere in the tropics, nothing of concern brewing and I don’t see that changing anytime soon. I’ll have an in-depth look at everything I mentioned in this post during my daily video discussion which will be posted later this afternoon.

M. Sudduth 7:10 AM ET June 3

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Gulf Stream aiding in comeback for Bonnie? Also, southern Gulf area to watch in coming days

Tropical depression Bonnie as seen in early morning visible satellite very near the NC Outer Banks

Tropical depression Bonnie as seen in early morning visible satellite very near the NC Outer Banks

The NHC will begin issuing advisories again on what was once TS Bonnie, now a tropical depression again very near the North Carolina Outer Banks.

It seems that the close proximity of the warm Gulf Stream has helped to refuel enough organized convection to aid in the recovery of the system. The main threat will be continued heavy rain and some gusty winds, along with locally rough seas (ocean and sound). I do believe the Hurricane Hunters will be flying a mission in to the area later today and we’ll know more about the wind field at that point. Right now, I am not seeing anything to suggest rapid strengthening though it would not be unreasonable to suggest that Bonnie could attain tropical storm intensity before all is said and done.

Unfortunately, the steering currents are still quite weak across the region and thus Bonnie will be aggravatingly slow to move out. It looks like by later tomorrow, the pesky storm system will finally move on out to sea. Until then, if you have plans to visit the Outer Banks or are there now, just keep in mind the fact that occasional bands of heavy rain will impact the area.

Meanwhile, we will soon need to turn our attention to the southern Gulf of Mexico where it looks like we may see yet another system try to develop some time next week.

Almost all of the reliable computer models are suggesting a broad area of low pressure will develop from energy piling in to the western Caribbean over the next few days. Upper level winds won’t be ideal but water temps are certainly warm enough and there is a decent chance that a tropical depression or even a tropical storm could form and head generally towards Florida.

GFS 850mb map showing energy associated with a broad area of low pressure in the Gulf of Mexico in about 5 days

GFS 850mb map showing energy associated with a broad area of low pressure in the Gulf of Mexico in about 5 days

One thing to keep in mind, the models are not indicating a very strong system, at least not yet. As an example, I have posted a pic of the overnight GFS model which shows the winds and vorticity (spin in the atmosphere) at the 5,000 foot level or what we all the 850 millibar level. This gives me an idea of how well organized or compact a given storm might be. The more round and “bundled” the energy, the stronger it is likely to be in the real world. Notice in the image, the energy is spread out over a fairly large area, not concentrated and totally symmetrical. This tells me that what ever develops could be more spread out and thus weaker than say a hurricane would be. Obviously this can change but for now, it looks like a lopsided, sheared system with plenty of heavy rain potential, which should never be underrated. From the wind and surge perspective, so far, there is not much to indicate any major issues. I will obviously continue to monitor the situation and will post regular updates here and via my daily video discussions over the coming days.

Last but not least, a tropical depression is likely to form in the east Pacific well to the southwest of Mexico over the next few days. No matter how strong it becomes, the track will be away from land with no impact what so ever for Mexico.

I’ll have more here early this evening on Bonnie and an update on the potential Gulf system as well.

M. Sudduth 8:55 AM June 2

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