The next five days

GFS model output showing the position of what would likely be a hurricane at day five. Here we see it approaching eastern Cuba after passing east of Jamaica and very close to Haiti.

GFS model output showing the position of what would likely be a hurricane at day five. Here we see it approaching eastern Cuba after passing east of Jamaica and very close to Haiti.

The very latest from the NHC indicates that we still do not have a tropical depression or a tropical storm from invest area 97L. In other words it remains a very well organized tropical wave of low pressure. That being said, it is producing winds of 40-45 mph in some of the heavier squalls as the entire system moves off to the west at around 15 mph. The Hurricane Hunter crew is currently flying through the area to sample the wind field and we will know by later this morning whether or not this is officially a tropical storm.

On the current track, the organizing system will pass through the Windward Islands today and bring with it more squally weather which will mean tropical storm conditions in some locations. Fortunately the low did not intensify quickly and as such we are not too concerned with much more than moderate tropical storm conditions at worst. By tomorrow, winds and seas will subside across the region.

Once the wave moves in to the eastern Caribbean Sea it is almost certainly going to strengthen. Water temps are very warm and the upper levels of the atmosphere support development. Some models are more robust than others but the bottom line is that this will be on its way to becoming a hurricane with time.

The track over the next five days will be very important for several reasons. First, we could see impacts as far south as Aruba, Bonaire and Curacao as what will eventually be a tropical storm passes by. Just how close to the north coast of South America this tracks remains to be seen but it is possible that it will be close enough for an increase in wind and rain by the weekend.

By late in the weekend and in to Monday, we should see a turn to the north as the western portion of the ridge of high pressure over the Atlantic begins to erode some. This will allow the sharp turn to the north that we are seeing in the model guidance. Some people have asked me how this is possible and has it happened before? It is possible due to the fact that the high pressure area, which is more dense an air mass than the tropical cyclone, relaxes some and allows the would-be hurricane to move north with time. It’s like holding a helium balloon down with your hand – once you move your hand away, which is essentially a form of high pressure, the balloon drifts up and away.

This type of set up was seen a few times in history but perhaps the most infamous was Hazel in 1954. Its track looks similar to what the models are hinting at for this system.

Around the five day time frame, it is possible for Jamaica, Haiti and Cuba to begin feeling the effects of what is more than likely going to be a hurricane. The GFS model is slightly east of the ECWMF or Euro model. The GFS moves the system over eastern Cuba and misses Jamaica but just barely. On the other hand, the Euro takes the center across Jamaica and then in to eastern Cuba. Obviously this needs to be monitored very closely by interests all along the islands of the Caribbean.

What happens after five days is the subject of much debate. Since we can all see the long range models now thanks to access on the Internet I won’t pretend to ignore it. Yes, I see the landfall in eastern North Carolina in about nine days. I also see the Eruo model taking a much slower path with a turn back to the northwest towards Florida by days nine and ten. I caution that these are extreme time frames when it comes to any large scale weather feature let alone adding a hurricane to the mix.

I for one am glad to see people talking about the models and the potential for impacts. It shows that people are in fact aware – it has their attention. That is a positive thing. We are so distracted by everyday news of politics, local and national issues, etc. that sometimes a bull horn is what we need to get people to pay attention. Knowing that there is a possibility of a hurricane threat for your area 10 days out is enough to get people motivated to at least keep track of it. Most people do not adequately prepare as they should well ahead of a landfall. Maybe the age of social media and the ability to share long range forecasts is not such a bad thing simply because it raises much needed awareness. No one I know is actually scared of a map. If they are, they need to dig deeper and ask questions about what the map means and how it might change. Social media allows for that too; it gets people engaged and talking and that is an advantage that many people can use.

So for now, let’s see what the Hurricane Hunters find and hopefully we can begin calling this what it is destined to be: Matthew. From there, the next five days are fairly straight-forward with regards to what happens. After that, no one knows for sure but it is great to see people paying attention.

I’ll have more later today.

M. Sudduth 8:15 AM ET Sept 28

Hurricane threat growing for Caribbean as long range outlook very uncertain

Morning model plots showing a general west track for the next several days.

Morning model plots showing a general west track for the next several days.

It has been a strange year for Atlantic hurricane activity. So many sputtering, long-lived but relatively weak systems have formed with minimal impact overall to land areas. Luck has been kind to us for sure but I am not so sure it can hold out for much longer.

We should have a tropical depression or possibly even a tropical storm by later today just east of the Windward Islands. We will know a lot more once the Hurricane Hunters fly out late today for on-site info from the low pressure area. Right now, it certainly looks like it is well on its way to developing but it needs a defined low level center of circulation and the recon crew can confirm whether or not that exists.

Whether or not this becomes a tropical depression or a storm before reaching the Windward Islands will not change the outcome for that region very much. Squally weather will move in beginning later tomorrow with tropical storm conditions likely across a good deal of the Windwards, especially to the north of where the center passes. Expect heavy rain, gusty winds and building seas as the low pressure area moves in.

Once past the islands, what should be Matthew at that point will have an opportunity to strengthen and become a hurricane. The upper ocean heat content in the Caribbean Sea is ample and could support a very intense hurricane if upper level winds allow.

As far as where the system tracks over the next five to seven days? More than likely, we’ll see a westward movement in to the central Caribbean not too far north off the coast of South America. As such, the so-called ABC islands could feel some impacts from this system. We simply need to wait and see to know the depth of those impacts as the week progresses.

Obviously areas such as Hispaniola, Jamaica, Cuba and the Cayman Islands should all be watching the progress of this system very closely. Before any possible impacts along the U.S. coast would happen, the islands along the northern Caribbean could be hit first. There’s no question about it, the next few days will be full of anxious moments as we wait and see how the steering pattern evolves.

A lot of talk has been made of recent runs of the GFS model which takes the storm/hurricane north out of the Caribbean and along or just off the U.S. East Coast. With a huge area of high pressure building over Canada and the Northeast this could be a bad scenario for a large stretch of coastline. But will it happen this way? It is impossible to know right now. Other model guidance shows a slower moving system that tracks farther to the west with potential tracks in to the Gulf of Mexico. Split the difference and Florida becomes a target.

So what do we do? My advice: just keep up to date with the latest info and be ready to react if this comes your way. No one has the answer right now. I sure don’t. It’s just like last year at this same time ironically when Joaquin was a threat to the Mid-Atlantic according to the American generated models. You remember that duel right? The Euro was the outlier it seemed and yet it turned out to be correct and Joaquin missed the United States. Right now we simply don’t have enough to go on in terms of making a forecast of where this ends up in a week to ten days. As I often say, it’s hurricane season and people should be ready for anything no matter what.

M. Sudduth 12:45 PM ET Sept 27

New tropical storm likely to develop as 97L moves west towards eastern Caribbean

Invest area 97L poisted to become a tropical depression as it nears the eastern Caribbean this week.

Invest area 97L poised to become a tropical depression as it nears the eastern Caribbean this week.

It is remarkable how well the GFS model in particular has “advertised” what we are seeing now and will see in the coming days. I first mentioned the possibility of something emerging from Africa back on September 21 and ever since then, the GFS has been locked on. Now, several days later, we have invest area 97L with a 90% of becoming a tropical depression or stronger over the next five days.

Right now, the system is still gathering itself over the deep tropics. It has a large area of energy and plenty of moisture to work with. Water temps are warm and the upper level winds are favorable. All of the intensity guidance eventually strengthens this system in to a hurricane but not until the eastern Caribbean Sea.

First up will be impacts for the Windward Islands. While it’s impossible to know exactly where the center will track let’s not focus entirely on that right now. Instead, let’s look at the hazards that are likely headed towards areas such as Martinique, Saint Lucia, Barbados, Grenada and Trinidad and Tobago. At the very least, squally weather will build in by early Wednesday morning it looks like. Heavy rain with gusty winds along with rough surf and larger waves will accompany the system no matter how strong it is at that point. It would not surprise me at all to see tropical storm conditions for portions of the Windward Islands as it appears that the low pressure area will be strengthening as it passes by. This is what people need to be ready for and not focusing on the center of circulation once it develops. The effects will extend well beyond the center – I know most people should know this but a friendly reminder never hurts.

After entering the eastern Caribbean Sea, what should be TS Matthew at that point is likely to intensify and become a hurricane as the week progresses. Upper ocean heat content will increase dramatically for the system meaning that there is ample fuel for it to become a formidable hurricane.

So what happens next? Obviously a lot of people want to know the answer to that question. I simply don’t know at this point. We are faced with yet another challenging forecast period with all kinds of variables thrown in from the possible interaction with northern South America to upper level low pressure areas digging in like we saw last year with Joaquin and almost every other scenario in between.

The model guidance beyond five days has been interesting to say the least. I won’t pretend that people can’t see the output from various social media and other hurricane related websites. One run of a model will show a hurricane moving in to the Gulf of Mexico. Twelve hours later, that same model has it turning north near Hispaniola. Let me make this very clear: we are talking about predicting the movement of a very complex weather system that will be interacting with equally complex pieces of energy, land masses and other unknowns that will ultimately shape the outcome. To think that we will have the solution six to ten days out is not a good idea. The wild swings from the various global models will be very interesting to watch but beyond five days exceeds the grasp of most in the weather community, especially when talking about a potentially powerful hurricane.

For now, let’s see how things develop over the next 48-72 hours and for interests in the Windward Islands especially, it’s time to pay close attention and be ready for impacts by mid-week.

As for how the story ends? I guess we will all find out together.

I’ll have more here later today with my video discussion followed by another blog post late tonight.

M. Sudduth 6:30 AM ET Sept 26

Recon had to abort mission in to 97L but doesn’t change outcome for Jamaica and points west

The tropical wave known as 97L still does not have a well defined low level circulation and is thus not a tropical storm as of now. However, the deep thunderstorms associated with it will bring heavy rain to Jamaica tonight

The tropical wave known as 97L still does not have a well defined low level circulation and is thus not a tropical storm as of now. However, the deep thunderstorms associated with it will bring heavy rain to Jamaica tonight

Quick early evening update on 97L.

The Hurricane Hunter plane suffered some mechanical issues and had to return to Mississippi before sampling the tropical wave that is nearing Jamaica. However, just because we don’t know for sure what the winds at the surface are or that the system is or is not a tropical storm doesn’t matter much. The effects for Jamaica will be the same – named storm or not.

So that being said, what can people there expect tonight? The main impact will be periods of heavy rain and squalls as the wave of low pressure and developing surface low passes by. It looks as though the loose center of circulation, what little of it there is right now, will pass south of Jamaica. This means a bulk of the shower and thunderstorm activity will rotate over Jamaica, approaching from the north and east.

Fortunately, the wave is still moving briskly to the west at 20 mph or so. This will keep the time period of heavy rain to a minimum but expect some localized flooding – something that is impossible to predict ahead of time in terms of precisely where.

Winds will be nearing tropical storm strength in some of the squalls and at higher elevations. Otherwise, this is a rain event and at least the island will receive some much needed fresh water – just not too much at once hopefully.

After passing Jamaica tonight, the wave should finally strengthen and become a tropical storm. From there, it’s hard to say how strong it might get. Water temps are as warm as they can get really and so it will all come down to the upper environment.

I’ll have more on the system tomorrow morning with posts to Twitter as needed throughout the evening and tonight.

M. Sudduth 5:35 PM ET Aug 1

Tropical storm forming in the Caribbean Sea – will be named Earl, track towards Jamaica, Yucatan

Invest 97L well on its way to becoming a tropical storm later today as convection and overall organization increases

Invest 97L well on its way to becoming a tropical storm later today as convection and overall organization increases

The difference between yesterday and now with invest area 97L is impressive. Satellite images show a much better defined area of deep thunderstorms or convection and improving outflow in the upper levels of the atmosphere. The NHC is reporting that winds are already over tropical storm force and that a surface circulation is becoming better defined. It won’t be long now until we have a tropical storm to track – its name will be Earl.

As I have mentioned several times already, water temps in the Caribbean, especially the western portion, are exceedingly warm. Once this storm forms, there won’t be much to hold it back from strengthening up until land interaction in a few days.

As for today, squally weather will begin to impact Jamaica and the Cayman Islands with fringe effects continuing for portions of Hispaniola. By tonight, it is possible that tropical storm conditions will be felt in Jamaica coupled with very heavy rain. The island needs the rain, so as long as it won’t be too much in too short a time period, what would be Earl could bring beneficial moisture to the area.

Track forecast models showing a fairly tight overall path for what would be TS Earl - headed generally towards the Yucatan peninsula and southern Gulf of Mexico

Track forecast models showing a fairly tight overall path for what would be TS Earl – headed generally towards the Yucatan peninsula and southern Gulf of Mexico (click to enlarge)

Strong high pressure to the north of the developing storm will keep it moving generally westward over the coming days. This will not allow the would-be storm to track in to the Gulf of Mexico – at least not until after crossing the Yucatan peninsula. Interests along the east side of the Yucatan need to be monitoring the progress of this system closely. It is possible that this system will go on to become a hurricane, especially considering the very warm water and high amounts of upper ocean heat content in the western Caribbean.

After passing over the Yucatan, depending on how far north the system would be, it could enter the southern Gulf of Mexico and strengthen again before making landfall well south of Texas. We can wait and see how well organized it becomes between now and landfall along the Yucatan before worrying too much about these details. Obviously the more time over land it spends, the harder time it will have intensifying again later on.

Elsewhere in the tropics, the east Pacific refuses to shut down. We now have TS Howard well off the coast of Mexico. It is moving northwest and towards cooler water and a more stable background environment. Howard should not pose any threat to Hawaii and will eventually die out over the open Pacific.

It is now August and in about two weeks, the rapid rise towards the peak of the season begins. If 97L goes on to develop in to a tropical storm and then a hurricane, it would put the season well ahead of where we should be for this time of year. Water temps in the Main Development Region and elsewhere across the western Atlantic are very warm. I have seen several indications that the next 45 to 60 days or so will be very busy in the Atlantic Basin. It’s never a guarantee one way or another, but the signs are difficult to ignore. It’s not the kind of season to sluff off and hope that nothing happens. With no El Nino and its associated strong shear machine cutting across the Atlantic, I feel as though we are in for a busy time going forward. If ever there was a season to be prepared compared to the last few, this is it in my opinion. If I am wrong, everybody on the coast comes out a winner. If I am right, and it’s not like I see this and no one else does, then hurricanes will be making headlines once again for the United States and elsewhere across the western Atlantic Basin.

I will have continuing coverage of 97L with frequent updates posted to Twitter (@hurricanetrack) throughout the day. I will also post a video discussion early this afternoon as well. Follow along in our app too, it’s on the App Store, search Hurricane Impact – all of my Tweets, blog posts and video discussions are posted to the app instantly. Get it and have everything all in one place!

M. Sudduth 10:30 AM ET Aug 1