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

Share

More going on in the tropics than we’ve seen in quite some time

It’s the end of August and the tropics are busy. We have a pair of hurricanes that are headed towards Hawaii, one in the Atlantic that poses no threat to land, two disorganized depressions and one significant tropical wave that has just emerged off of Africa. Did I miss anything? I think that’s it. So let’s look at each area beginning in the central Pacific…

Hurricane Madeline

Hurricane Madeline track forecast from the Central Pacific Hurricane Center

Hurricane Madeline track forecast from the Central Pacific Hurricane Center. Click for full size.

Just a couple of days ago the forecast for Madeline did not indicate it would even reach hurricane strength. My how that changed – it is now a category four with winds of 130 mph. It is currently moving west but is expected to track a little south of west over the next day or so and this just might keep the core of the worst weather south of Hawaii where a hurricane watch is currently in effect for the Big Island.

The official forecast brings the center fairly close and the Big Island would be within the right-front quadrant of the hurricane as it passes by. This is usually the stronger side of a hurricane relative to its forward movement and as such, it is possible that hurricane conditions could be experienced throughout portions the region. In addition, dangerously high waves along with very heavy rain could cause localized damage. Hawaii is a unique geographic location for hurricanes to impact and so pinpointing the effects is hard to do; so much depends on the eventual track and intensity. Needless to say, residents and visitors on the Big Island need to be preparing for a hurricane today and tomorrow in anticipation of Madeline’s arrival or close passage sometime on Thursday.

Hurricane Lester

Meanwhile, off to the east of Madeline is hurricane Lester with winds of 125 mph, down from a peak of 140 yesterday.

The good news here is that Lester is currently forecast to track to the north of the islands over the next few days and should also weaken considerably while doing so. As such, I am not nearly as concerned about impacts from Lester as I am about Madeline for Hawaii.

There will be another increase in the swells and local high surf due to the intensity of Lester in recent days. While the surfers in Hawaii can take advantage of this, novice swimmers should avoid tangling with the big waves headed to the area.

Satellite photo showing hurricane Gaston, TD8 and TD9

Satellite photo showing hurricane Gaston, TD8 and TD9

Hurricane Gaston

Moving along in to the Atlantic where hurricane Gaston has weakened some overnight. Top winds here are 100 mph but there is a large eye apparent on satellite imagery. It is possible that the hurricane could strengthen again over the fairly warm waters of the subtropical Atlantic. Gaston is only an issue for shipping lanes as it will likely turn northeast out over the open water with an increase in forward speed.

TD8

Tropical depression 8, just off the North Carolina coast, is trying to wrap deep thunderstorms around its well defined center of circulation this morning. It won’t take much for it to strengthen over the very warm water and become a tropical storm. If it does so before TD9 does, it would be named Hermine.

The effects overall will be minimal with a few passing rain bands and locally gusty winds at times for the Outer Banks of North Carolina. Even the waves will not be too much of an issue since the wind is not very strong right now but locally higher surf is possible within any squalls that happen to make it to the coast.

The forecast is for the depression to possibly become a tropical storm and then turn north and eventually northeast and away from land.

TD9

The forecast for TD9 remains very complex which seems to have been the case ever since it was just an area of interest or tropical wave several days ago.

During the overnight hours, deep thunderstorms have managed to expand and possibly cover the low level center. If this is the case, it might be that we finally have a tropical storm out of this system. The Hurricane Hunters will be investigating the depression off and on today and we’ll know more later if it’s not obvious based on satellite that it has in fact strengthened.

Overall the idea of a Florida Big Bend area landfall on Thursday seems intact. The question is really more about how strong it manages to get before that time. Upper level winds are not particularly favorable but could be just enough so that the depression makes it to tropical storm intensity plus perhaps a little more strengthening after that.

I see two main impacts from this system that concern me. First, storm surge flooding along the immediate coast. The area of Florida that the system is forecast to move in to is very vulnerable to storm surge from tropical storms and hurricanes. The onshore flow, combined with the fact that the would-be storm will be pushing water in the direction that it is moving means several feet of inundation is possible. We won’t know how much is being predicted until later on and especially so when and if it becomes a tropical storm. Areas in the Big Bend region down to the Nature Coast should be prepared for some coastal storm surge issues on Thursday – this includes an increase in wave action as well along what is normally a very placid Gulf of Mexico.

Rainfall forecast over the next few days highlighting the chance for excessive rain totals in parts of Florida.

Rainfall forecast over the next few days highlighting the chance for excessive rain totals in parts of Florida.

The other significant impact will be the heavy rain. Several inches is likely to fall across portions of Florida and this will lead to areas of localized flooding. It’s impossible to pinpoint which areas will receive the most rain and when but it’s a good bet that north-central Florida will see rainfall totals exceeding 5 inches with isolated higher amounts.

I am not as concerned about the wind since the model guidance does not suggest a very high chance of this becoming a hurricane. However, the official forecast calls for 65 mph near landfall which is enough to knock down some trees and cause minor damage to property. Scattered power outages will also occur but it all depends on the final intensity near the time of landfall.

Once inland, the threat of heavy rain will spread in to southeast Georgia and northern Florida as the storm system moves towards the Atlantic. From there, things get very interesting. It is possible that we will see quite a ramping up of intensity once it gets out over the very warm water and begins moving off to the north and east. It is possible at that point that it could become a hurricane.

We will have to watch closely how the pattern evolves over the coming days as there is some hint in the models that the system could track fairly close to the coast as high pressure tries to build in across the western Atlantic again. If it gets blocked enough, it is not out of the question that another landfall or very close approach to the coast could take place farther north. This is something we can worry about later on but it is beginning to show up in some of the models so keep that in mind along the Mid-Atlantic states and points north. I’m not too concerned just yet but the trend has my attention.

I am planning to head down to Florida tomorrow to set up a couple of our unmanned cameras along the immediate coast. I will also have the ability to provide live wind and pressure data from the on-board weather station atop my Chevy Tahoe. I will not set out any additional weather stations for this event but will have a live stream coming from the vehicle so that I can relay instant wind readings as I record them on the anemometer.

I will outline not only the goings on in the tropics but also my plans for setting up the cameras along the Gulf Coast of Florida in anticipation of the landfall on Thursday during my video discussion which I will post early this afternoon. This will be followed by another blog post early this evening.

M. Sudduth 8:30 AM ET Aug 30

Share

Mixed signals mean low confidence forecast for TD9

I am going to address TD9 in this blog post and will cover the other activity around the Atlantic and what is going on in the Pacific in my video discussion to be posted early this afternoon. With all of the interest in what happens with TD9 and its potential impact to Florida, I figure I would tackle that first.

Some deep convection has developed with TD9 in the region around wetern Cuba and just south of the island. Whether or not this is the start of a strengthening trend remains to be seen. Click for full size image.

Some deep convection has developed with TD9 in the region around wetern Cuba and just south of the island. Whether or not this is the start of a strengthening trend remains to be seen. Click for full size image.

During the overnight hours, deep thunderstorms began to develop in association with the depression in the vicinity of western Cuba and even to the south of the island. It is not clear just yet if this convection is near the low level circulation center or if perhaps that center has reformed closer to the thunderstorm activity. We will know more as morning visible satellite images come in and recon flies in to the system later today.

For now, the NHC is classifying it as a tropical depression with winds of 35 mph. The forecast is very uncertain due to a variety of mixed signals in the overall pattern for the days ahead.

Normally, a tropical depression over the Gulf of Mexico this time of year would be concerning. While it is somewhat concerning this time around, the limiting factors are fairly substantial.

First of all, strong winds blowing across the top of the depression from north to south are likely keeping the convection removed from the low level center. This is extremely important to the health of the depression and until the shear relaxes, assuming it ever does, we won’t see much strengthening.

Most of the models that do develop the depression in to a tropical storm or a hurricane do so in a couple of days – not in the immediate future. So we have some time to watch and see how the upper level pattern evolves over the eastern Gulf of Mexico. With water temps in the upper 80s in most areas of the Gulf, it won’t take much to allow the system to ramp up quickly.

The other issue is dry mid level air that would need to be mixed out in order for more efficient convection to take place. Dry air is a stable environment and tends to limit the amount of thunderstorms a tropical cyclone can produce. It is not clear whether or not the dry air will remain a limiting factor. Here too, if it abates and the low can generate deep thunderstorms, it’s only a matter of time before it starts intensifying.

Track forecast model plots showing a fairly tight clustering of the models in the Big Bend area of Florida. This could change over the next few days.

Track forecast model plots showing a fairly tight clustering of the models in the Big Bend area of Florida. This could change over the next few days. Click for full size image.

The track forecast is also tricky since we are talking about several days out for one and secondly, Florida’s western coastline is shaped that changes in the course of the would-be storm will have potentially huge impacts on who feels what effects.

For now, the official forecast calls for the center to pass in to the Big Bend area of Florida, in the northeast Gulf of Mexico. This is concerning to me because the region is very prone to storm surge, even from “weak storms”. Obviously a hurricane would be worse but even moderate tropical storm winds can push several feet of water onshore within portions of the Big Bend region.

The next area of concern is Tampa Bay. While most of the model guidance suggests a track farther north, we need to watch this closely since this area is also very susceptible to storm surge from even minor tropical storms.

It appears that it will all come down to the mid level trough that is forecast to come in and erode the strong high pressure area that steered the depression in to the Gulf in the first place. At some point, it will round the western edge of the high and begin turning more north then northeast. When and where this happens will determine what part of Florida receives the most substantial impacts. Obviously the intensity will come in to play at that point as well. It’s still just too soon to know with any degree of confidence – something we have grown accustom to dealing with concerning this system.

For now, I think that the biggest impact will be heavy rain and the possibility of storm surge flooding along the coast. It goes without saying that if the depression becomes a hurricane, those impacts are elevated quite a bit. We’re going to have to wait it out and see what happens with the upper environment over the next few days. The NHC makes it very clear in their forecast that the intensity portion especially is of low confidence. Sometimes that’s just the way it goes.

As I said, I will have a full video discussion posted here by early this afternoon. I will go over the very latest on TD9 plus what to expect as we watch TD8 off the North Carolina coast. Meanwhile, Hawaii is watching TS Madeline and hurricane Lester very closely as both could bring impacts to the region later this week. I will also discuss the coming week to 10 days and what to look for as we head in to September.

M. Sudduth 8:20 AM ET Aug 29

 

Share

Tropics getting very busy as we close out August

There is a lot going on, no doubt about that. It’s the end of August and the hurricane season is kicking in to high gear. Let’s start in the Pacific actually then move east from there…

TS Madeline/Hurricane Lester

TS Madeline is forecast to strengthen in to a hurricane as it tracks generally towards Hawaii in the coming days. It should weaken upon approach and perhaps turn more south with time.

TS Madeline is forecast to strengthen in to a hurricane as it tracks generally towards Hawaii in the coming days. It should weaken upon approach and perhaps turn more south with time.

We have a pair of tropical cyclones to watch closely in the east and central Pacific over the coming days. First up is tropical storm Madeline which is currently situated well to the east-southeast of Hawaii. The forecast calls for the storm to reach hurricane intensity as heads generally westward early next week. While the track suggests a threat to Hawaii, it seems as though less favorable conditions will set in and Madeline will weaken and probably push more south with time, avoiding a direct impact to the islands. However, as we know, this can change so it’s obviously a good idea to keep tabs on the progress of this storm.

Much farther to the east over the eastern Pacific we have hurricane Lester with 100 mph winds. It too is tracking almost due west and could reach the vicinity of Hawaii in about a week. It is something to monitor but remember, it is very difficult for hurricanes to make landfall in Hawaii from the east. We usually see hurricane threats from the south as they turn from lower latitudes and track northward across the region, such as Iniki did back in 1992. While Lester is a strong hurricane, I would not worry too much about it right now – plenty of time to watch.

99L

Morning track plots showing the spread of the various computer models. Most of the more reliable models suggest a landfall, if it were to develop, somewhere along NE Gulf of Mexico coast.

Morning track plots showing the spread of the various computer models. Most of the more reliable models suggest a landfall, if it were to develop, somewhere along NE Gulf of Mexico coast.

Next we have good ole 99L. Seems like it has been with us forever. The area of interest that just can’t seem to develop. So far, it still hasn’t and doesn’t look like it will anytime soon. Upper level winds continue to plague the would-be storm, pushing any deep thunderstorms that try to develop away from the low level center which is currently moving through the Florida straits and Keys area.

It has been a frustrating week tracking 99L with all of the computer model flip-flopping that we’ve had to deal with. About the only one that has been consistent with intensity is the hurricane specific HWRF model which goes bonkers with development on almost every run. So far, none of that has come to pass. The GFS has done fairly well indicating little development thus far and not much more to speak of in the days ahead. The Euro or ECMWF on the other hand has gone back to suggesting a hurricane threat for Florida and possibly the Southeast coast once the system moves back out over the Atlantic.

My feeling is that so far the system has under-performed and until the shear relaxes and we see deep convection wrapping around the low level center and maintaining for 24 hours or more, it won’t pose much of a threat as far as being a strong hurricane. That being said, it is possible that 99L could reach hurricane intensity somewhere in the Gulf of Mexico next week. Water temps are very warm and all it takes is a period of favorable upper level winds for the lid to come off.

I believe the next 24-48 hours is the key here. If we see it develop by Tuesday then folks in Florida could be in for some significant impacts from this system. Unfortunately we will just have to wait and see how things pan out. For now, it remains only a strong tropical wave of low pressure, nothing more.

91L

Invest area 91L with some deep thunderstorm activity near the center. It is moving towards the NC coast but should turn north and back out to sea before reaching Cape Hatteras and vicinity.

Invest area 91L with some deep thunderstorm activity near the center. It is moving towards the NC coast but should turn north and back out to sea before reaching Cape Hatteras and vicinity. (click to view animation)

Next we have invest area 91L between Bermuda and Cape Hatteras and moving westward with a turn more to the west-northwest expected soon.

Right now, strong upper level winds coming from the east are keeping the convection that has managed to develop just west of the well defined low level center. You can clearly see this on the satellite image I have posted here. In fact, this looks to me like it would be classified as a tropical depression but without recon in there to verify right now, it’s not officially anything but an area of interest. We should know later today once the recon crew gets in there – perhaps this becomes TS Hermine? We shall see.

The models are in pretty good agreement that this will turn more to the north and then curve back out over the Atlantic over the next couple of days. The key to any appreciable impacts to the North Carolina coast will be how close the system tracks before doing so. Most of the guidance keeps it just east of Cape Hatteras and vicinity but close enough to warrant concern, especially for off-shore boating interests.

I’ll keep a close eye on this one since recon is planning to investigate later today. Once we get their reports we will know if this has in fact become a next named storm or at least a tropical depression.

Hurricane Gaston

Hurricane Gaston track forecast showing it staying out over the open Atlantic.

Hurricane Gaston track forecast showing it staying out over the open Atlantic.

Gaston has become the strongest hurricane in the Atlantic Basin for 2016. Top winds are near 90 mph and are forecast to go up from there. The hurricane has developed an eye and is moving away from all of the hostile conditions that were hindering significant development over the past day or so.

The NHC is forecasting Gaston to reach peak intensity of 110 mph before reaching cooler water later this week. I won’t be at all surprised to see the hurricane reach 120 mph or more over the warm water of the sub-tropics. This seems to be the norm in recent years – hurricanes reaching peak intensity well outside of the deep tropics. Fortunately for land areas, Gaston will only be tracking over open ocean.

Future 92L in the far eastern Atlantic

Large tropical wave over Africa that will almost certainly be a named storm in the far eastern Atlantic in the coming days.

Large tropical wave over Africa that will almost certainly be a named storm in the far eastern Atlantic in the coming days.

A well developed tropical wave over interior Africa is forecast by all of the global computer models to move in to the eastern Atlantic and develop over the next five days. Conditions appear to be favorable across the entire swath of ocean this time around and we just might have something to track for days on end.

There is no doubt going to be a lot of talk about this system because the steering pattern looks to be one that could allow it track all the way to the United States. While this is a possibility, it is so far out in time that worrying about a specific location is pointless. Conditions appear to be favorable so let’s just watch and see what happens over the course of the week ahead and go from there. We have plenty of other issues to deal with on the west side of the Atlantic to keep us busy for a while longer.

I’ll post an update here later this afternoon or early evening once we get more info from the recon crew concerning 91L. I don’t think much will change with 99L today but if there is, I’ll certainly update that as well.

M. Sudduth 10:10 AM ET Aug 28

Share

When 80% is not enough

Wednesday, August 17 at 2pm ET the National Hurricane Center issued the first outlook on what would become probably the most talked about area of interest (invest) in the history of mankind. That outlook began a process that kept scores of weather geeks, emergency managers, TV meteorologists, weather forecasting firms and the general public glued to their Internet-connected devices. From the get go it looked like this could be “the one”. It had potential to make it all the way across the Atlantic and possibly affect the United States after roaring through the Caribbean. And so here we are at the other side of that long journey and what became known as “99L” to millions of people will long be remembered for what it didn’t do: failed to develop.

As the process of tracking the tropical wave got underway, computer models were generally in agreement that the system would move westward at a fairly low latitude. However, it was clear early on that mid-level dry air, somewhat associated with the Saharan Air Layer (SAL), would be an inhibiting factor for development. Never the less, by early Saturday morning the 20th, it looked as though a tropical depression would form. Chances went from virtually nothing to 50% in just three days.

By Monday evening the 22nd, the probability increased to 60% and it looked as though a hurricane was possible for the southwest Atlantic Basin, maybe even close enough to Florida or the Carolinas to warrant concern. The social media hurricane machine was in full throttle mode with every expert (and non-expert) opinion you could imagine being thrown in to the mix. It was “invest 99L” overload and it would only get worse.

Leading the charge for development at first was the dynamic duo of the GFS and the ECMWF. Both seemed to latch on to 99L and make something of it. At first, it looked like a track towards Florida and then a turn north was likely. At times, the GFS had an enormous hurricane sitting not too far off the North Carolina coast, moving harmlessly out to sea in the longer term. It looked like this would be a close call but no guarantees yet for a landfall.

As the days went by, seemingly very slow considering we can watch the computer models come and go virtually 24 hours a day, things began to change. The GFS dropped the development almost completely while the ECMWF put memories of Katrina, Andrew and Betsy in our collective minds. It wasn’t just the Euro, the new and improved HWRF model, which is specifically designed to forecast tropical cyclones, showed similar forecasts of a hurricane headed towards south Florida and then turning west as it tracked south of a strong high pressure area over the mid-Atlantic. The hurricane world went in to full meltdown mode. It had been since before Twitter, Facebook as we know it, the iPhone and even the birth of One Direction that Florida had been hit by a hurricane. It was Tuesday, August 23 and 99L had a 70% chance of developing in to at least a tropical depression. The “H” word was bound for Florida.

To make matters worse, the ECMWF ramped up 99L to beast mode and sent it towards Louisiana, the LAST PLACE that needs a hurricane this season. Meanwhile, the GFS showed almost nothing at all. Just weak energy coming across and never really doing much. People were scoffing that if the Euro was right, congressional hearings needed to take place immediately to “fix the GFS!”. It was pure madness because, you know, the ECMWF nailed Sandy’s forecast from 8 days out. People were hung up on a hurricane from four years ago, forgetting the failures of even recent events like Erika last season and Fiona in 2010. Oh yeah, let me tell you about that one.

In 2010, we had Earl, headed for a possible landfall up the East Coast. Meanwhile, the ECMWF was advertising Fiona to be “the next Katrina”. A few in the weather business bit off on this and ran with it like the end times were coming. Earl was going to be a dud while Fiona would be a disaster of epic proportions. All the while, the GFS showed Earl doing exactly what it ended up doing: coming close to the NC Outer Banks then turning out to sea as a strong hurricane. As for Fiona, the GFS showed it as nothing more than a nuisance and that’s how it all turned out. GFS right, Euro wrong. Funny how few people remember that. I remember, trust me, I was on the Outer Banks where Earl brought 85 mph wind gusts to our anemometer that was set up next to Oregon Inlet.

By Wednesday morning, just 48 hours ago, the chance for 99L to develop made it to 80%. It looked like a sure thing now. I mean 80% is pretty good, right? In basketball an 80% free throw shooter is considered to be almost lethal from the line. You foul that player and you might as well put two points on the board. Eight times out of ten the shots go down.

But what happens when that player is in the title game and his team is down 1 with .90 seconds on the clock and he is fouled driving to the hoop? Everyone holds their breath as he lofts the first shot to tie the game. He misses. It’s stunning. The announcers balk about his percentage and how they can’t believe he missed. Must be the immense pressure. Time for try number two. He misses. No one gets the rebound and the clock expires. His team loses the National Championship for one simple reason: 80% is not enough. It’s not 100%. There was a 20% chance he missed either of those two shots. Now this is purely hypothetical but it makes my point. Sometimes high probability is mistaken for certainty.

In the case of 99L, it looks dead and gone now. The GFS, in its past few days of runs, turned out to be correct, for the most part. No hurricane coming for south Florida this weekend like the Euro showed. To be fair, the HWRF did as well and it busted big time. Instead, the Euro now has weak energy bringing possible heavy rain to portions of Florida. No hurricane in to Louisiana or elsewhere, just a strung out mess.

Odds of development over the next five days are down to 60%. Strong wind has all but beat the system in to oblivion. There is virtually no convection or thunderstorm activity with it and the USAF Hurricane Hunter crew has been grounded since there’s nothing there to investigate.

Sixty percent. Hmmmm. That’s not too high nor is it very low either. What is the reason behind this number? It’s because there is still a chance, apparently a 60% chance as of this writing, that 99L will develop some in the Gulf of Mexico. How could this be? The Euro “dropped it”. Well, the ever-excited HWRF sure didn’t and the GFS now shows limited development in a few days with some rather wacky tracks thrown in for good measure. To be honest, it’s giving me a headache to watch this day in and day out and all we have is an area of interest, even if fading to an area of blue skies.

I caution that while the gist of my post is aimed at pointing out the obvious, that anything short of 100% probability has a chance of falling short, it is also true that unless it’s zero, there’s still a chance. Even the 60% free throw shooter is sometimes the hero.

There is still some energy down in the region near the southeast Bahamas that might be able to survive long enough to warrant keeping an eye on. None of the computer models that show any development potential do so until later in the weekend – so let’s see what happens. Perhaps 80% was too high early on but 60% will be just enough for now.

We want to be able to trust the computer guidance to give us time to prepare if in fact something is going to develop. However, the public should understand probability and know the limitations of forecasts even in the relative short term. Most people don’t have time or interest to fully invest their energy in to making sense out of it all. I do my best and could not for the life of me understand why the GFS gave up on this system while the Euro did not. Sometimes you need to look out the window, so to speak, and view the actual weather and not just the predictions. The satellite presentation of 99L never really looked promising for development. It came close a couple of days ago but the reality was it didn’t have that “look”. So logic should have dictated that if it looks poor and one of the major global models insists on non-development, then maybe that’s why: because it won’t. It’s a simple concept and for now, it turned out to be right. Shear and lack of convection and overall organization has kept 99L from developing but it’s not necessarily over.

I think the next 48 hours will be all we need to know how this ends. If nothing happens by then and the wave of energy basically spreads out or dissipates completely, then we’re golden. Until that happens, it’s obviously prudent to keep an eye on things – just in case 60% is just enough to do what 80% could not.

I’ll have more in my daily video discussion posted here, to our app and on YouTube later this afternoon.

M. Sudduth 9AM ET Aug 26

Share