Rare January tropical activity in Pacific, possible subtropical storm for Atlantic

You have no doubt heard plenty about the record-setting El Niño in the Pacific. It has been blamed for a litany of foul weather across the globe; whether all of those events are directly related to the El Niño remains to be seen.

Now we can add a rare January tropical storm to the list of El Niño-induced weather anomalies. The Central Pacific Hurricane Center (CPHC) is tracking tropical storm Pali, well to the southwest of Hawaii, not far from the Equator actually.

Check out the tracking map and you’ll see that the storm is located unusually far to the south and this is likely one of the reasons why the storm formed in the first place. Add the very warm El Niño water and a perfectly-timed westerly wind burst from the tropics and the result is a January tropical storm.

Tropical storm Pali tracking map from the CPHC

Tropical storm Pali tracking map from the CPHC

No worries about Pali – it is forecast to basically meander slowly well away from significant land masses and poses no threat to Hawaii. Still, it is yet another in a series of interesting, if not record setting, events that the current El Nino is at least indirectly associated with.

Meanwhile, the Atlantic, or more accurately, the subtropical Atlantic, has its own storm system worth watching.

Ocean storm in the vicinity of Bermuda that has a chance to become a subtropical storm over the next few days

Ocean storm in the vicinity of Bermuda that has a chance to become a subtropical storm over the next few days

The National Hurricane Center issued a special outlook product yesterday highlighting a strong ocean storm between the Bahamas and Bermuda. While currently non-tropical in nature, meaning that the storm has more or less the characteristics of a Nor’easter over warm water, there is a chance that environmental conditions, part of which also include warmer than usual water temps, could lead to the storm becoming more subtropical in the coming days. This basically means that the storm separates itself from any frontal boundaries in the vicinity and becomes more focused with deeper convection or thunderstorms closer to the center. This is typical of ocean storms that form out of the tropics or what we call the subtropics. Thus, it’s deemed a subtropical storm, kind of a first cousin to a classic warm-core tropical storm that we are more used to tracking during summer and fall.

Right now, the type of storm matters little for interests in Bermuda. The weather has been stormy for the past day or so with periods of heavy rain and gusty winds. The fresh water collected on the string of small islands is always appreciated but this unusual weather pattern is making for an unpleasant few days for the region.

Computer models indicate that the storm system will move generally east-southeast and make its way in to the open subtropical Atlantic. Water temperatures are not warm enough for a pure tropical storm to develop but it is possible that enough energy can be drawn from the Atlantic to allow the storm to acquire what I described before: more subtropical characteristics. If so, it would be named and would be Alex, subtropical storm Alex that is.

Once past Bermuda the storm poses no threat to land and is likely to be on the weather map for quite a few days since steering currents look to leave it hanging around out over the Atlantic in to next week.

So there you have it. The year is starting off with some interesting things to talk about even in the face of an obvious lack of cold and snow for most of the East. Will this change anytime soon? Probably. For now, the most interesting weather seems to be over the oceans with little sign of any big winter storms looming for the Lower 48. However, it’s still early January, as with hurricane season, we know how quickly things can change.

I’ll post more on the Pacific and Atlantic systems over the weekend.

M. Sudduth 8:40 AM January 8

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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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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

 

 

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Tropics busy but nothing set to impact land

Atlantic looking fairly busy considering the strong El Nino season

Atlantic looking fairly busy considering the strong El Nino season

We are closing in on the mid-point of the hurricane season in terms of climatology- September 10th marks the traditional peak of the season. Despite a fairly strong El Nino currently dominating the Pacific, the Atlantic Basin has managed to eek out enough activity to keep the maps active. Today is no exception with several areas to monitor in the coming days.

First, we have TS Grace which is likely to weaken and eventually dissipate somewhere in the Caribbean, if not before. It may bring additional rain to the region but it shouldn’t be too much and hopefully nothing like what Erika brought to Dominica recently.

Grace has little chance of making it to the United States as a tropical cyclone due to the persistent band of strong upper level winds and dry mid-level air situated over the deep tropics.

Next up is invest area 92L which is situated to the east-southeast of Bermuda this morning. The NHC says that it consists of a broad area of low pressure that is supposed to be nearly stationary over the next day or two. Water temps in the region are quite warm and most computer guidance suggests that this will become a tropical depression and perhaps a tropical storm before heading on out in to the far north Atlantic. No worries in Bermuda except for a possible increase in surf as the system organizes.

Elsewhere, a rather innocent looking tropical wave is moving through the southeast Caribbean Sea that could end up in a position where it could fester and try to develop down the road. The global models have been hinting at development somewhere in the western Gulf of Mexico within about a week. In fact, for what it’s worth, the often reliable ECMWF has been rather consistent with this scenario over the past few days. Right now, it’s just something to take note of but nothing more. I think that within 72 hours we’ll have a much clearer idea of what may or may not take shape in the Gulf of Mexico as we get in to next week.

Hurricane Linda satellite photo

Hurricane Linda satellite photo

In the east Pacific, hurricane Linda remains well offshore of Mexico and is expected to weaken as it moves to the northwest with time. However, this morning, it sure seems like it’s on a strengthening trend with a clearer eye showing up in satellite imagery. There is likely to be an increase in the wave action along portions of the Baja as the hurricane moves past but the heavy weather should remain far enough to the west to limit any additional impact. Some high-level moisture may get pulled northeast in to the Desert Southwest later in the week as the hurricane has a large circulation associated with it.

I’ll have a thorough video discussion posted later this afternoon that will take a closer look at all of the happenings in the tropics.

M. Sudduth 8:50 AM ET Sept 8

 

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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

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