Field mission to Florida about to begin

I am prepping to leave for Florida and the Big Bend region in anticipation of TD9 strengthening to near hurricane intensity as it moves towards the NE Gulf later tomorrow.

There is so much to cover that I figure a video discussion is a good way to get it done. I will post video updates throughout the mission, especially later today and tomorrow. Follow along in our app, Hurricane Impact

I will be setting out two live unmanned camera systems along the Gulf Coast late tonight or early tomorrow morning to show the storm surge as it comes in to the area. I plan to have one in Cedar Key and one in Suwannee and will post the links to view them once they are up and running.

I will not be taking the mobile weather stations with me since I will need to turn around and get back to North Carolina in short order to perhaps set one up along the Outer Banks Friday. It’s going to be a long and grueling few days but the reporting I can do from the ground will be worth it. I hope you will follow along.

M. Sudduth 8:50 AM ET Aug 31

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Conflicting signals in the computer models for 99L

Visibile satellite image showing 99L (left) and TS Gaston (right). Click to view full size.

Visibile satellite image showing 99L (left) and TS Gaston (right). Click to view full size.

It has been a very interesting few days when it comes to what may or may not happen with invest area 99L. As of this morning, there are still no easy answers despite the apparent better organization of the tropical wave.

The NHC is indicating a 60% chance of further development over the next five days. As of this writing, there is currently a Hurricane Hunter crew heading out to investigate the system and that will help tremendously with a better understanding of the structure and local atmospheric conditions.

What has changed somewhat in the past day is the fact that one of the best performing global models, the ECMWF, has begun developing 99L in the vicinity of the Bahamas and sends it in to Florida. Other models have followed such as the U.S. generated HWRF which did very well last season with Joaquin – once it formed. I will not worry too much about the intensity indicated by the various computer guidance but it goes without saying that the very warm water temps that lie in the path of 99L make for a concerning few days ahead.

As I mentioned, the organization of the tropical wave appears to be improving. Deep thunderstorms or convection has blossomed and managed to stick around and even expand in size as of late. This could be a sign that it will finally begin to form a low level circulation and slowly start its ramp up in intensity. The Hurricane Hunter crew will be able to observe that and relay that information to the NHC almost immediately.

Recent computer model projections for invest area 99L. The track could potentially bring heavy rain and gusty winds to portions of the NE Caribbean and the southeast Bahamas

Recent computer model projections for invest area 99L. The track could potentially bring heavy rain and gusty winds to portions of the NE Caribbean and the southeast Bahamas

With all of this being said, let’s talk about short-term impacts. As it looks now, 99L will move towards the extreme northeast Caribbean Sea later today and tomorrow. This will result in periods of squally weather for portions of the northern Leeward Islands, spreading west towards Puerto Rico and maybe Hispaniola. Heavy rain and gusty winds are to be expected with some areas receiving more than others depending on the actual track and how well organized it becomes. Flash flooding is a concern for any mountainous terrain of the Caribbean islands that the tropical wave interacts with.

Next up will be the southeast Bahamas. The same scenario holds true here – periods of heavy rain, possibly bands of it if the system goes on to develop. Winds could increase more so than we will see in the Caribbean, it all depends on how quickly 99L can form a low level center – if at all. Needless to say, interests in the Bahamas should be paying close attention to the progress of this developing weather system.

It’s what happens later in the forecast period that has a lot of people quite interested, and rightfully so. The overnight models have shown a marked trend towards the west with time once the system reaches the northern Bahamas in about 4 to 5 days.

We all know by now what tends to happen with tropical cyclones when they turn west under a strong area of high pressure anchored over the Southeast U.S. It usually does not end well. Now, there is a fine line between being informative and discussing the pattern and trying to just get people anxious over potentially nothing. With social media, it is easy to spread graphics showing cat-4 and 5 hurricanes hitting some specific locale. I will not do that unless it is part of the official forecast. Right now, we don’t even have a tropical depression and there is no guarantee that we ever will.

If I live in Florida along the east coast especially, I am just going to pay closer attention to this system and be ready to act if need be. The one major downside to this NOT being named yet is that it might not command the attention and respect that it would if it were a tropical storm, for example. On the other hand, I think enough people are aware who would normally be that they won’t be caught off guard.

It’s been a long time, over 10 years, since a hurricane of any strength has made landfall in Florida. While there is a chance that streak ends sometime within the next 10 days, it is impossible to say for certain whether or not that comes to pass. It’s the heart of hurricane season. You live in Florida. You should be prepared every year as if it’s the year for your area to be hit. Beyond that, we will have to wait and see and let nature literally take its course. The data will be plentiful with recon missions planned from here on out. That will help to get a better handle on current conditions. From there, we can plan based on what happens as things evolve. It’s usually not easy and this situation seems to be no exception.

In the mean time, if you like watching harmless hurricanes roam the ocean, then Gaston is tailor-made for you. Right now, it is a tropical storm but is forecast to become a hurricane and last for days and days out over the open Atlantic. This will add to the seasonal ACE score in a big way, likely leading the way in making 2016 the busiest season in four years – pretty much as predicted by most groups that issue such forecasts.

In the eastern Pacific, the are two well organized disturbances that are both likely to go on to become tropical storms and eventually hurricanes. The good news: both are well away from Mexico and moving generally west with no impacts to land.

I will post my daily video discussion here later this afternoon followed by another blog post late tonight. Follow along as well in our app, Hurricane Impact, for blog updates, social media and video info right on your iOS device. Search Hurricane Impact in the App Store.

M. Sudduth 10:15 AM ET Aug 23

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Complicated forecast for 99L, easy one for 90L

Convection or thunderstorm activity has increased substantially over night with 99L. You can also see here that invest area 90L is well on its way to becoming a tropical depression.

Convection or thunderstorm activity has increased substantially over night with 99L. You can also see here that invest area 90L is well on its way to becoming a tropical depression.

As I mentioned yesterday in my blog post, it looks as though invest area 99L will continue to struggle and not be much of an issue for land areas anytime soon. However, the recent development of convection or deep thunderstorms suggests that perhaps things are changing, even if only a little bit right now.

The very latest info from the NHC indicates that development chances are going up slightly – now up to 50% in the five day time frame. It appears the warmer sea surface temperatures and a better overall environment are slowly playing in to favor of this system developing.

One aspect that I cannot get over is the large size of the overall envelope of energy with 99L. It is not a small, weak and fragile tropical wave. It’s quite the opposite in fact with a large area of circulation and deep precipitable water profile. What this means is that this feature is not just going away despite the marginal conditions in the atmosphere. As we have seen in the over night hours, convection actually began to increase and persist with 99L and this morning, the satellite shot indicates continued slow organization. If this continues, we may have something to deal with in the coming days as it moves generally WNW towards the Caribbean Sea. Interests in the northern Leeward Islands, Puerto Rico and Hispaniola need to monitor 99L closely. At the very least, it could bring periods of heavy rain and gusty winds as the week progresses.

5 day tropical weather outlook grpahic showing the likely development areas and tracks for 99L (orange) and 90L (red)

5 day tropical weather outlook grpahic showing the likely development areas and tracks for 99L (orange) and 90L (red)

The longer term outlook for 99L is tough to call right now. So much is based on whether or not it goes on to fully develop in to a tropical depression or a storm. Generally speaking, the weaker and shallower in the atmosphere a system is, the farther west it tracks under the low level flow pattern. For now, the NHC is showing a potential track area extending up in to the Bahamas by later this week. There are some indications that the track could be farther south but we will have to wait and see about that. Very warm water temps await this system and if conditions improve aloft, it could be an interesting week ahead with not much time to prepare should this threaten land areas from Florida northward to the Carolinas. While this is not indicated by any particular solid forecast right now, it goes without saying that the closer this gets to the U.S. the shorter the time frame for reacting will be.

As for the short term, I want to emphasize again that this large wave energy should bring heavy rain and squalls to portions of the Caribbean Sea over the next few days. Do not count 99L out just yet. It’s late August, water temps are very warm and we have a large system heading westward. Let’s not get caught off guard.

Meanwhile, what should become the season’s next hurricane, and a strong one at that, is developing in to a tropical depression right now far out in the eastern Atlantic.

The NHC should begin advisories on TD7 later today. The model guidance is in excellent agreement that it will strengthen quickly in to TS Gaston and eventually become a hurricane. I see nothing to suggest that this will ever affect land but it will add to the seasonal ACE score, something that is tracked to help size up the quality of the storms/hurricanes that form.

In the eastern Pacific, a pair of disturbances well off the coast of Mexico both have a shot to develop as they move west to west-northwest out in to the open Pacific. No other areas of concern are seen over the next several days for Pacific Mexico or the Baja peninsula.

I’ll have more here in my daily video discussion. Also, you can follow all of my updates using our app, Hurricane Impact, available in the App Store. This blog, social media posts, video updates and field mission reports/data all goes in to the app. We’ve had it since 2012 as a great way to keep up with HurricaneTrack.com info while on the go. Search “Hurricane Impact” on the App Store.

M. Sudduth 8:15 AM ET Aug 22

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Slower development means more of a chance for impact later

Recent satellite shot showing invest 99L and the limited convection associateed with it currently. This will allow the tropical wave to move farther to west since it will not be influenced by any weakness in the subtropical ridge, allowing it to turn out to sea.

Recent satellite shot showing invest 99L and the limited convection associated with it currently. This will allow the tropical wave to move farther to the west since it will not be influenced by any weakness in the subtropical ridge.

It looks as though the Main Development Region or MDR is still struggling in terms of the ability for tropical cyclones to take shape. The area between Africa and the Lesser Antilles is usually fertile grounds for development this time of year but it seems that for the past several years, dry air has been the rule. The result is we see vigorous tropical waves move off of Africa, various computer models over-develop them and then nothing much happens. It’s like the models (some, not all) are simply not “aware” of the dry, more stable environment that has become a semi-permanent feature of the deep tropics.

However, this is not necessarily a good thing in the end. I’ll explain why…

It is actually quite simple. The longer a tropical wave takes to develop, the farther west it will track. The low level easterly flow which is dominant in the tropics this time of year pushes the tropical waves generally westward. If they don’t develop at all, they often end up in the southeast Pacific and try to develop there. It’s when they don’t develop until they get past about 60 degrees west longitude that is problematic for land areas.

Think about it, a larger storm or hurricane in the atmosphere will more than likely feel the effects of the mid-ocean trough that is usually waiting to allow systems to turn north and eventually northeast and away from land. Sometimes, like 2008, the subtropical ridge of high pressure is so well established that even hurricanes such as Ike can make it from Africa to Texas. Obviously this is rare – otherwise no one would want to live on the coast of Texas or anywhere else for that matter – the hurricanes would be too numerous year after year.

On the other hand, a shallow tropical wave, void of deep convection or thunderstorms, can sail along with the easterly trades and gain longitude day after day. Eventually, conditions improve and a tropical depression forms. By now, the system is nearing the eastern Caribbean and it will most certainly bring squalls, heavy rain and brief high seas to the region.

Hurricane Earl is an example of this scenario. The parent tropical wave struggled as it raced westward across the tropical Atlantic and in to the Caribbean Sea. It was not until it reached the western Caribbean that it developed and became a hurricane. It made landfall in Belize instead of developing early, way out in the MDR, and turning out to sea.

So what does this have to do with anything currently going on in the tropics? Perhaps it has huge relevance. This is because as we watch the recent trends with 99L, we have seen some of the models delaying development until it is only a day or so away from the Caribbean Sea. This ends up sending a slowly strengthening tropical system in to the region, bringing heavy rain and other hazards to the region. Beyond that time frame, anything seems possible, including threats to the United States.

Even though we expect development out in the open Atlantic, just because it doesn’t happen there doesn’t mean it won’t happen at all. The farther west these tropical waves track, the warmer the sea surface temps get. It’s only a matter of time, I believe, until we see something strengthen quickly and close to home. I just don’t know whose home yet.

Bottom line – over the coming days we will see a lot of variations of the “end result” for 99L and perhaps even Fiona and soon-to-be 90L coming off Africa now. The down side to delayed development is that more people take notice when a hurricane is coming from seven to ten days out. It makes sense, the hurricane is there longer and it gets more attention and more people know about it. If it blossoms later, like Katrina did in 2005 (5 days from tropical storm to landfall) then it gives us all less time to react.

The next few weeks will likely be very busy with one named storm after another forming in the Atlantic Basin. Some will be possible impact threats, others will not. It will be important to keep up with what’s going on at least daily if not more. The advantage of seeing a hurricane coming from a week out might not be there and as such, being ready in case one pops up with only 72 hours to prepare will be more important than ever.

I will go over this topic in greater detail on today’s video discussion which I will post here. You can also follow along in our app, Hurricane Impact, available on the App Store. All of our blog posts and video discussions are posted to the app for easy access on the go. Plus, the app has incredible landfall features which I will talk about more when and if the time comes.

M. Sudduth 12:20 PM ET Aug 20

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Consensus growing for active hurricane season

We are now less than three weeks away from the start of the 2016 Atlantic hurricane season and already it looks to be a busy one. Before we jump to the “sky is falling” conclusion, let’s look at things objectively and put it in to some perspective that most can understand.

Subsurface anomaly chart showing the growing area of cooler than normal water mounting in the tropical Pacific

Subsurface anomaly chart showing the growing area of cooler than normal water mounting in the tropical Pacific

What we know is that the great El Nino of 2015/16 is almost certainly dying out. We can see this by looking at various data from a variety of sources. One of those is the subsurface anomaly chart that I have included here. Clearly the warm surface water is being eroded away with a vast expanse of cooler than normal water lurking across most of the tropical Pacific. This will very likely herald the arrival of La Nina conditions or an abnormal cooling of the Pacific along the equatorial region. In short, this is typically seen as a favorable sign for the development of Atlantic hurricanes. The sooner we see La Nina set in, and the stronger it is, the more influence it will have on enhancing the chances for Atlantic hurricane development once the season gets going.

In addition, we also know, again by looking at actual data, not computer model projections, that the Atlantic Basin is warming in the area between Africa and the Lesser Antilles. This is also called the MDR or Main Development Region. The irony here is that there were some indications in previous weeks that this region would actually cool abnormally; so far, it has done the opposite.

Check out the very latest NOAA/NESDIS SST anomaly map for the region. Water temps are running above normal across the entire MDR and in to the Caribbean Sea. This is a stark difference from what we saw last season although the MDR did warm some as the season progressed. Right now, the region is warmer than we have seen it since the 2013 season and this, coupled with the loss of the El Nino, should give another check mark in the column of enhanced hurricane Activity for the Atlantic.

Latest NOAA/NESDIS SST anomaly map showing a very warm tropical Atlantic

Latest NOAA/NESDIS SST anomaly map showing a very warm tropical Atlantic

Warm water alone does not make hurricanes. The atmosphere needs to cooperate as well with aspects such as moisture level and wind shear being take in to account. Right now, those parameters don’t matter too much since it’s just May. However, conditions do seem to be a little less dry in the mid levels of the atmosphere in parts of the tropical Atlantic which is yet another indication that things may be busier than we’ve seen for quite some time. Shear will drop as the summer approaches and the westerlies retreat to the north. Once we get to August, the beginning of prime time for the season, it looks like all systems go for a busy time ahead.

With all of this mounting evidence for a busy season, it comes as no surprise that several respected agencies are forecasting either an average season or slightly above average. So many different entities are making forecasts now that it’s hard to keep up. The trend however is what is interesting to me. All of them see a busier Atlantic than the past few seasons and that will seem very busy considering how relatively quiet things have been since 2012. We will get a new forecast from Dr. Phil Klotzbach and his team at CSU in early June. NOAA will release their seasonal outlook soon as well. I think it is safe to say that, at least for now, the scale has tipped in favor of the Atlantic.

None of this matters as far as who would be impacted. I need to make that very clear. Knowing that the general large scale environment favors more hurricanes is helpful, I think anyone would agree with that. You’d rather know than not, right? Just don’t get caught up in the headlines and lose sight of the fact that even a 40 mph tropical storm can ruin your entire life – or even end it. It’s all about the impact (hence why our app is called Hurricane Impact) and no forecast can tell you with any degree of certainty what impact you will face this season.

The bottom line here is that you’re going to hear a lot about the “busy hurricane season” coming up. What you won’t hear as much about is how you can process that information and make use of it. My advice is to use that info to beef up your knowledge of hurricanes and what to do if one comes your way. A busy season does not necessarily equate to one with many (or any) landfalls. It does up the chances but no one really knows by how much. That part of the equation comes down to timing and placement of the would-be hurricane within the Basin.

It’s almost time. We are ready and hope to help you to be as well.

I’ll have more here on the 15th when the east Pacific hurricane season begins.

 

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