Recon crew finds 99L not organized enough to be TD or TS yet

Visible satellite image showing a fairly disorganized tropical wave moving through the NE Caribbean Sea

Visible satellite image showing a fairly disorganized tropical wave moving through the NE Caribbean Sea

The value of the Hurricane Hunters is priceless. Their work and dedication is without equal in the weather world. Today, they proved it again with the flight in to invest area 99L. The data indicates that while the overall structure of the tropical wave has improved some, it’s not quite enough to name it a depression or a tropical storm.

Instead, we have a broad area of lower air pressure and plenty of general turning in the cloud motion. However, there is some fairly strong wind blowing over the top of the system and this is injecting dry mid-level air while also pushing any deep thunderstorms away from the weak low level center.

We can see this in the satellite image I have included here. Notice that the clouds are not symmetric in appearance but rather pushed off to the south and southeast. While there is clearly a weak circulation nearing Puerto Rico, it has yet to completely close off and become well defined. It may take another day before that happens which is generally what the models that develop this system indicate.

So for now, we still have a tropical wave but it is bringing with it strong winds and periods of heavy rain for portions of the islands of the NE Caribbean Sea. This will continue to spread WNW towards the Turks and Caicos and eventually the southeast Bahamas.

For what it’s worth, the latest GFS model run indicates once again that 99L will remain a weak system and never really impacts Florida. I do not understand why this is the solution the model is coming up with but it cannot be dismissed completely. We just don’t know – despite the insistence of the very reliable ECMWF or Euro model that this will become a hurricane and enter the Gulf of Mexico. Once I get a look at the latest output from this morning’s ECMWF run, I will post an update here, followed by a thorough discussion in my afternoon video blog. If you have our app, Hurricane Impact, be sure to check the video section later today for that update.

M. Sudduth 1pm ET Aug 24


Gonzalo likely to become a hurricane within next 24 hours as it passes through NE Caribbean

Track forecast for Gonzalo showing it passing east of Puerto Rico tonight

Track forecast for Gonzalo showing it passing east of Puerto Rico tonight

The overnight model runs and latest forecast track from the National Hurricane Center dictate that I not go to Puerto Rico today for Gonzalo. This does not mean I think the island will have zero impact but I don’t believe it will be significant enough to warrant me traveling there. Sometimes the weather makes the call and this is one of those cases I do believe.

So far, Gonzalo is managing to steadily increase in strength. Winds are now 60 mph with a falling pressure. The storm is quite small in size compared to something like Irene which passed through this region three years ago in August. This should serve to keep the strongest winds confined to a rather small radius around the storm. It also means that, if an inner core can become established, Gonzalo has a chance to increase in intensity quickly.

For the Caribbean islands today and tonight, it’s all a matter of where the bands of convection set up, rotate through and how that impacts the various islands in the path of the storm. Computer models cannot possibly resolve this to any degree of accuracy and thus local radar is the best tool for watching in real time.

Right now, the movement is steady at around 12 mph. The heading is 280 degrees which would bring the storm through the northeast Caribbean, probably passing 60 miles or more to the east of Puerto Rico but directly over the U.S. and British Virgin Islands. Almost all of the computer model guidance suggests this path as being quite likely over the next 18 to 24 hours. This would keep Puerto Rico on the west side of the small circulation and unless a more westward motion ensues, I see little wind impact for the island. Rain, on the other hand, could be problematic as and bands that move through could drop a quick inch or more, adding up to over 4 inches in places, especially at higher elevations.

Obviously, boating interests throughout the region need to simply stay in port until the storm passes by later tonight. Winds and seas will be highest between now and the next 24 hours or so with much better conditions setting up for mid-week and beyond.

Once Gonzalo gets out of the Caribbean and in to the Atlantic, the set up is quite ripe for substantial strengthening. Model data suggests that Gonzalo could reach near category three intensity over the very warm water of the Atlantic. This will send swells back towards the northern Caribbean islands as well as the Bahamas and parts of the Southeast coast later this week. Surfers will love this but swimmers should be on the lookout for potential dangerous surf conditions. I will address this more in tomorrow’s post.

The track forecast after the Caribbean is extremely important for one small area: Bermuda. The odds of the center passing directly over Bermuda are quite small yet Fay did it just the other night. It is possible that Bermuda will have to deal with a direct impact from Gonzalo but it’s too soon to know for sure right now. We’re talking about 5 days out, maybe less. Needless to say, interests in Bermuda should be watching Gonzalo very closely over the next couple of days.

This is where I will be focusing my attention now as well. If it looks like a close enough pass of Gonzalo will take place in Bermuda, then I will head out there as soon as Thursday to be ready. It’s a tough, tough call since the island is quite expensive to travel to on many levels. Yet, an October hurricane hit from the southwest is something that rarely happens there, so the chance to gather data and document the event with video is something I don’t take lightly. I think that even passing within 50 miles of Bermuda would bring hurricane conditions and so it is something I will be monitoring quite closely today and tomorrow.

Elsewhere in the Atlantic, Fay is moving quickly across the northern reaches and will soon transition in to a more typical large ocean storm than a concentrated tropical cyclone. Only shipping interests will be concerned with its progress.

In the Pacific, a low pressure area, labeled as invest 95C (for Central Pacific) is likely to become a tropical storm and eventually a hurricane to the east-southeast of Hawaii. As rare as it is, there is at least a chance that it will move in that direction over the next several days. For now, it’s just something for folks in Hawaii to monitor but after a quite tumultuous season in the Pacific, it would not surprise me in the least to see one more impact for the String of Pearls. I’ll talk more about this in tomorrow’s update as well.

The MJO or Madden-Julian Oscillation is likely to be quite favorable for development over the next couple of weeks

The MJO or Madden-Julian Oscillation is likely to be quite favorable for development over the next couple of weeks

Things are quite busy for mid-October and we’re likely not done yet. Long range guidance suggests that the Gulf of Mexico or western Caribbean Sea could become more active as we move through the next week to 10 days. It is part of a quite favorable period called the Madden-Julian Oscillation moving through the Western Hemisphere over the next couple of weeks. This means that the overall upward motion of the atmosphere is enhanced and allows for more tropical convection to flourish. There will be quite a bit to keep track of I believe before the month is over. For now, we’ll see what Gonzalo does but do not be shocked if we’re talking about a potential storm brewing somewhere in the western Caribbean of southern Gulf of Mexico next week.

I will have another update on Gonzalo here tonight and a full run down of the tropics tomorrow morning.

M. Sudduth 8:47 AM ET Oct 13


Tropics going to be news maker this week

It seems more like mid-September than approaching mid-October in terms of activity in the Atlantic Basin. We have a hurricane, Fay, and newly designated TS Gonazlo, forecast to become a hurricane and move through portions of the northeast Caribbean Sea. It is going to be a busy week ahead.

First up, Fay. After lashing Bermuda with 80+ mph winds last night, the storm strengthened in to a hurricane and is now moving quickly out in to the north Atlantic. There’s not much else to say about Fay except that it just goes to show that intensity and track forecasts are not exact sciences. No one thought that Fay would bring hurricane conditions to Bermuda several days ago when it was a mere “subtropical storm”. Fay will track out in to the open Atlantic and only be an issue for shipping interests.

Now we turn our attention to Gonzalo. The NHC upgraded 90L to tropical storm Gonzalo this afternoon. The forecast is aggressive and makes the storm a hurricane as it passes by Puerto Rico on Tuesday. As noted in the 5pm NHC discussion, there is a chance that Gonzalo undergoes rapid intensification if it develops a well defined eye. If this happens before cross in to the Caribbean, then numerous islands in the path will have to deal with a potentially powerful hurricane.

Right now, the forecast calls for strengthening and a track that would cut across the northeast Caribbean, passing very close or over eastern Puerto Rico. This would put the U.S. and British Virgin Islands right in the middle of the core of the potential hurricane – not a good place to be obviously!

The next 24 hours will be extremely important as Gonzalo fights off dry air that occasionally tries to disrupt the intensification process. Water temps are very warm and only the dry air is an inhibiting factor right now. Interests across the northeast Caribbean need to be making preparations for a strengthening hurricane. Remember too this is not just about wind but also rain. The mountainous terrain of Puerto Rico is susceptible to flash flooding and mudslides as Gonzalo passes by.

With all of this going on, I am preparing to head to Puerto Rico tomorrow morning. I will be working with The Weather Channel to provide (hopefully) exceptional live video and weather data from the area. This is my first time leaving the Lower 48 to intercept a hurricane. I arrive mid-afternoon and will have to quickly get things set up and running. Along the way, I will post video blogs and updates via our app, Hurricane Impact, and through Instagram (follow @hurricanetrack). The weather data will stream to the app and update every minute with wind, pressure and a live image from the station’s location in Puerto Rico. A lot will depend on the exact track and intensity of Gonzalo but odds are that hurricane conditions will be felt in parts of Puerto Rico and surrounding areas. It is going to be an interesting mission to say the least. I am ready and look forward to capturing what ever Gonzalo dishes out.

I will do my best to update the blog throughout the next few days. I am going to ask colleague Mike Watkins to fill in while I am out, so look for posts from him starting tomorrow.

I leave North Carolina at 7:30 AM – I’ll have more from Puerto Rico tomorrow afternoon.

M. Sudduth 8:45 PM ET Oct 12


Watch 96L closely this weekend

Current radar from San Juan, Puerto Rico

Current radar from San Juan, Puerto Rico

As of this writing, the convection associated with 96L is beginning to burst and is likely bringing heavy rain and gusty winds to portions of the northeast Caribbean Sea. Areas such as Puerto Rico and the Dominican Republic could see quite a bit of rain as the tropical wave and its weak low pressure area move through today.

So far, 96L has not become all that better organized but this has been expected per most of the reliable intensity models. Even the NHC makes mention of this in their outlook and we shouldn’t expect to see much strengthening until later in the weekend.

Once the system passes Hispaniola and vicinity today and tonight, it will begin affecting the southeast Bahamas with periods of heavy rain and general squally weather. It’s this point in time that we could see it begin to organize more and eventually become a tropical depression followed by a tropical storm. In fact, the NHC says this scenario is “likely” over the weekend.

Beyond the next couple of days, the forecast is very complicated for both track and intensity.

Right now, 96L is still a loosely organized, weak tropical low. Some of the intensity forecasts do increase the winds to hurricane force over the next few days. Other models do not see it that way. Water temps are plenty warm and vertical instability should become more favorable in the coming days. This means that we should see a steady increase in strength over time. Also, going by what we’ve seen so far this season, I would expect an increase in strength once the system gets north of about 24 degrees of latitude. It seems that we’re seeing tropical cyclones in the Atlantic (both of them this season anyway) reaching their peak intensity once clear of the dry, sinking air of the deep tropics. Do not be surprised if 96L eventually becomes the 3rd hurricane of the Atlantic season.

The track forecast is about as muddled as I’ve seen in quite some time. There’s been a lot of talk about this system reaching the Gulf of Mexico – at least earlier this week. Now, we have a lot of chatter about it simply turning out to sea, possibly impacting Bermuda. What people fail to realize is that the pattern is always changing and computer models are not as reliable as we would like to think. And in this situation, it’s even more complex due to the pattern that we happen to be in.

Basically it’s like trying to catch a bus. Let’s say for the sake of this discussion that 96L becomes a named storm which it is likely to do – the name will be Cristobal. It wants to catch the bus by virtue of finding a weakness in the Bermuda High or western Atlantic ridge, which ever term you like to use. That escape route is there now but seems likely to close and block the exit, forcing Cristobal to wait for another bus. This is becoming more and more plausible with each passing model cycle. Case in point – the ECMWF, highly regarded as the top global model on the planet, now gets the would-be storm much closer to the North Carolina coast than any other run of that model. And just this morning, the GFDL, for what it’s worth, looks eerily similar to the track of Sandy in 2012, bending what ever 96L does in fact strengthen in to back towards the Mid-Atlantic coast.

Yes, there are plenty of other model solutions that send the system off to the northeast, passing by or close to Bermuda and out to sea. My point is that we are starting to see more and more evidence that a possible threat to the Carolinas and points north from this system is not out of the question as we get in to next week.

It’s all a matter of timing – seems like it’s always that way, doesn’t it? Sometimes the forecast is fairly cut and dry and it’s a matter of who gets the impacts instead of if they get the impacts. In this case, we know that the Caribbean islands and eventually the Bahamas will feel some effects as the low moves through. After that – no one knows for sure but I’m here to tell you, I’ve seen it enough in the past to know not to write off something that is only a few days away from the U.S. coastline. School is starting back for many kids along the East Coast and families will be very busy with that (I know I will starting Monday morning). It is important, in my professional opinion, that people along the Southeast coast up to the Mid-Atlantic watch this system very closely. As I have said before, we can hope it heads out to sea but rest assured, hope is not a planning tool.

I’ll post more here tonight.

M. Sudduth 9:36 AM ET Aug 22


Bertha bringing beneficial rains to parts of northeast Caribbean

Recent radar out of San Juan, PR showing much needed rains moving across the region

Recent radar out of San Juan, PR showing much needed rains moving across the region

There is one positive about tropical cyclones – they often bring much needed rain to areas and as long as it’s not too much, too soon, it really can be a good thing.

Such is the case today with TS Bertha. Puerto Rico and surrounding islands have been very dry in recent months. Bertha is helping just a little with some much needed rain. While there is the risk of flash flooding, especially in the mountainous terrain, Bertha’s quick movement and disorganized structure will help to limit this impact. It looks like another 12 to 24 hours at the most and the rains will move on, passing over parts of the Dominican Republic and in to the extreme southeast Bahamas tomorrow and Monday.

Bertha has probably lost its well defined low level center and may not technically be a tropical cyclone – more of a strong tropical wave. This was not unexpected and while it might not ever recover, the computer models are actually in pretty good agreement that Bertha will eventually become a hurricane.

Once the storm moves out of the Caribbean, the environment in the atmosphere is forecast to be much more suited for development. Fortunately, Bertha will be well east of the United States and sufficiently west of Bermuda to avoid any direct impacts.

I do see the potential for increased swells and rip currents along parts of the East Coast later next week. I’ll have more on this once we see how strong Bertha does in fact get over the western Atlantic. Anyone with plans to head to the beach will want to just make sure you’re aware of the local surf conditions ahead of time. While it could be a nice few days for surfers, rip currents and rougher than normal breaking waves are a danger, especially to children who may think big waves are exciting while not understanding the risk.

Latest GFS model showing two potential impacts for Hawaii in the coming days

Latest GFS model showing two potential impacts for Hawaii in the coming days

Meanwhile, in the Pacific, we will need to watch hurricane Iselle closely in the coming days. It is likely to track far enough west as a tropical storm that it may bring rain and wind to Hawaii later next week.

As if this were not enough, global models are indicating the formation of another tropical cyclone to the east of Iselle which could also track west enough to impact Hawaii. The next 10 days are going to be quite interesting for the region as the Pacific has really come to life with a lot of tropical activity.

I will post more on all of these systems tomorrow morning.

M. Sudduth 12:38 PM ET Aug 2