#Ian Sunday (25 Sept) Morning Update

Summary: Ian is still forecast to rapidly intensify today. Western Cuba is bracing for a Cat 3 landfall, and Ian could be a Cat 4 by Tuesday Evening. The Florida Keys are on alert but likely to be on the fringes, no actions at the moment. The models then start to diverge, but landfall in the Big Bend or panhandle of Florida on Thursday or Friday is likely. Here’s the details …

For the latest as always check the National Hurricane Center’s Key Messages regarding Tropical Storm Ian (en Español: Mensajes Claves). Based on the 5am forecast, here is what the impact/damage swath looks like as of the 5am forecast:

click to embiggen.

The track through 60-72 hours (late Tuesday) seems pretty clear. The Cayman Islands are under a hurricane warning but should only see the fringes of the storm – how bad depends on the exact timing of the explosive intensity growth of the storm. Impacts to Cuba are likely to be in excess of $1 Billion USD based on this forecast, with over a million people in the tropical storm wind swath, with the worst of the impacts staying west of Havana. Conditions are ripe for rapid intensification: by Tuesday Ian could well be a strong Category Four (120 knots, 138 mph) hurricane.

After that things get fuzzier. Ian is expected to sneak around the edge of a decaying frontal system and start to turn northeast (as well as encounter an unfavorable environment, which should knock the intensity down). As NHC says in their 5am discussion:

With the cross-track spreading remaining between 200-220 n mi at days 4 and 5, it cannot be overstated that significant uncertainty remains in Ian's long-range prediction.

Here is what that looks like graphically using the TAOS/TC model dispersion analysis tool. Notice how the nice neat circles suddenly turn into an elongated ellipse and the range for the 120 hour forecast is from near Mobile Bay to off of Cape Canaveral:

click any image to enlarge.

As you can see NHC split the difference between the models, with GFS being on the left edge and the European models (UK, ECM) on the right. While a landfall in the panhandle seems most likely, we probably won’t have a good handle on this until late today or tomorrow. The exact track will make a lot of difference for evacuations, as the “target rich” environment of the Sarasota-Tampa-Clearwater region is or is not in play. Being that close to a Cat 4 storm, a small wobble will make a huge difference in impacts. Those on the west coast of Florida and panhandle need to pay close attention and be ready to implement your hurricane plans – probably starting tomorrow (Monday). So you should check this afternoon to see what’s going on, and certainly listen out regularly starting in the morning.

As for Coastal GA/SC, The Cone of Shame Cometh(*)! In other words, Coastal GA is within the NHC uncertainty cone, the zone where there is a 2/3 chance the center of the storm will pass. It hasn’t crept in to South Carolina yet but should do so today. The media often makes a lot of this, but what does it mean? in terms of impacts not a lot – you can be in the cone and not feel much, you can be out of the cone and get high winds that cause a tree fall on your house. So the cone says nothing about impacts, which is what we care about.

It’s still hard to tell what the impacts will be in this region. It’s likely that the coast, from Jacksonville to Charleston, will see high onshore winds for a day or two with conditions deteriorating Wednesday and tropical storm conditions offshore with the appropriate marine advisories. On the barrier islands that means gusty winds, rain, and a likelihood of some shallow coastal flooding at high tides. Nothing terribly dangerous is expected, but as we all know even a foot or two of extra water causes a lot of damage. How bad depends on how close and slow the storm moves by. Again, we won’t know more about that until Monday.

It wouldn’t surprise me to see school closures and other impacts for Thursday or Friday spreading across the region. Depending on the exact track, conditions inland will likely be rain and gusty winds, depending again on how far inland and how rapidly the storm decays. Right now, Thursday looks to be the worst day in the Savannah/Beaufort area, with winds 20mph gusting to 30mph and some rain squalls. Inconvenient, hazardous if you lack common sense, but not dangerous. Further south, in Brunswick conditions might flirt with tropical storm conditions, starting late Wednesday. So inconvenient (especially if power outages!), but not at this point looking at much in the way of actual damage. Again, this is all pretty uncertain; we’ll have a better picture in the morning (Monday), but that is to give you an idea of what to expect. It will be worth paying attention to local advisories for later this week to see what actions local emergency managers recommend. No need to wear out your refresh key at this point, check back in Monday morning, and Tuesday for sure start checking for what your local community is doing.

(*) Those of you with animals are probably familiar with the Elizabethan collar, aka the “Cone of Shame,” that has to be put on critters sometimes to prevent them from tearing off a bandage or licking/chewing on an injury.

Tropical Storm #Ian; #Fiona makes landfall

The forecast picture for Tropical Storm (and likely Hurricane) Ian and the extent of risk to Florida and, more importantly, Coastal GA/SC 😛 is becoming clearer. Fiona isn’t really a hurricane any more even though it has hurricane force winds, and has made landfall in Canada. We’ll start with a quick look at Fiona, then move on to the latest on Ian and what it means for the Southeastern US.

Click any image to embiggen

This is Fiona at 6:30am this morning, shortly after crossing Cape Breton Island. Winds across northern Nova Scotia and southern Vinland (Newfoundland) are probably still in the 125-145 kph (80-90mph) range, so that’s power outages, trees down, roof and minor structural damage, that level of damage. Weaker structures (which are more rare up there, due to the nor’easters and snow loads) and those unlucky enough to be hit by trees and debris would be more heavily damaged. Definitely a mess, economic impacts probably on the order of $1 Billion USD. And speaking of Fiona, let’s not forget Puerto Rico, which took heavy damage and tends to drop out of the news cycle, and will (once again) probably be ignored if a major storm hits the US next week, as looks likely. The Dominican Republic was hit hard as well and needs help.

Of course in the US, Tropical Storm Ian is moving through the central Caribbean and is still forecast to enter the Gulf of Mexico and probably curve in to Florida. Here are NHC’s latest Key Messages regarding Tropical Storm Ian (en Español: Mensajes Claves), and the damage swath based on the 5am ET Saturday forecast:

Jamaica may get heavy rain (which means flash floods and landslides) from Ian, as will Cuba and the Cayman Islands, who will get wind/waves/storm surge as well. But the fear is once the storm passes the Caymans, conditions are ripe for rapid intensification. For Florida, this track does bear some resemblances to that of Hurricane Charley in 2004. That storm hit the Sarasota area hard, and caused over $25 Billion in adjusted damage. For what it’s worth (nothing, really) the models are showing Ian to have the potential to cause up to $15 Billion in damage to Florida on this track and intensity. So Florida should be watching, and be ready to start taking action Monday if needed, especially areas like the Keys that take longer to prepare.

The later part (days 3-5) of NHC forecast has been drifting westward the last couple of cycles, and will probably continue to be adjusted in that direction. Here are the computer models that NHC was looking at. A bit of a rant point here, and why I keep harping on the fact you really shouldn’t be obsessing over the model tracks, is that forecaster judgement also goes in to their analysis. If you want to understand their forecasts, great, look at the models! But don’t think you can do a forecast on your own just based on models (and for sure don’t trust anyone who spends more time discussing models than the NHC forecast, unless it is used to help understand the NHC forecast!). Here is what the major global models look like, along with a dispersion analysis (a measure of how much they have changed over the last 12 hours):

The blue marker labeled “XX Global Model Dispersion” is the average position of the models would say the storm would be in XX hours. The yellow/golden ellipse is a measure of where you would expect the storm to be given how scattered the models are (in other words, we expect the storm to be somewhere in that yellow area at each time) As you can see, the NHC track is to the right of the guidance for most of the track. In the early part of the track, this is because the storm isn’t very organized, and the models are probably starting the storm offset somewhat, and NHC probably wants to make sure Jamaica and the Caymans aren’t duped into thinking the storm will be farther from them than it is likely to be. By the time the storm is expected to reach Florida, on Wednesday evening, only the European Model is to the right of the NHC track (in red, with orange markers at each time). Another consideration by NHC is they want to avoid what they call the “windshield wiper” effect – they don’t want to shift the track left, then have to shift it right six hours later. That risks confusing people and reducing confidence in the forecast, as well as causing shifting watch and warning areas. So they do the sensible thing and watch for trends, not jump on every wobble of every model. That’s what you should do, too – watch for trends, and not freak our over any one forecast (or any model).

Folks in coastal Georgia and the Lowcountry of South Caroina have been freaking out because some of the long range tracks show the storm moving our way. Is that justified? How about no, if you have a hurricane plan (and if you don’t after slapping yourself go here, get a checklist, and figure out what you’re going to do). On the current track and forecast, we are increasingly likely to get some impact from the storm, most likely gusty winds and rain next weekend. But it’s WAY too early to speculate. It will probably be Monday morning before there is anything solid to say about impacts to anything north of Jacksonville. So enjoy the beautiful weekend!

TD 9 (new storm) forecast: Is Florida Doomed?

Well, yes, it is Florida after all. But what about the new storm that formed in the Caribbean? Will it hit the US? How bad will it be? Lets take a closer look.

11am update: nothing much changed. Will probably be tomorrow before we have anything substantive to talk about, although it’s likely TD9 will be upgraded to a Tropical Storm this afternoon or evening. It’s a race between TD 9 and TD10 (off of Africa) who gets named as Hermine and who gets stuck with Ian.

Here are the Key Messages regarding Tropical Depression Nine (en Español: Mensajes Claves) and the TAOS/TC impact estimate based on first official forecast, issued at 5am this morning (Friday 23 Sept):

click to embiggen.

NHC is expecting TD9 to slowly become a tropical storm over the next day or two, then a hurricane before potentially exploding in to a Category 2 or even 3 storm before approaching Florida by next Wednesday.

So how likely is this scenario, and what happens next? The short answer is we don’t know yet – the storm is really just organizing, and while the model spread is rather tight at this stage, there is a reason the NHC only goes out to five days in their forecasts. Although some of the models go beyond that (up to 10 days in fact), due to the complexities of tropical cyclones they just aren’t that reliable beyond the five day forecast. And unless you have some specialized needs, five days is plenty of time to get organized and do what you need to do. To give you an idea of the complexity of this, here is the official track (pink line with markers) and the major computer models.

So you can see that the trajectory threatens Jamaica, Cuba and Florida, but then, even with this rather close grouping, the possible storm paths are from The Bahamas (European model) to into the Gulf of Mexico, with South Florida being in the track of most of the models. Just yesterday several models (including GFS at one point) had landfalls as far west as Texas. Just because the models “converge”, while that’s a good sign, they can all be wrong for the same reason (usually a misrepresentation of the initial conditions). We’ll have better simulations later today or tomorrow, as the shear lessens and the environmental setup becomes a bit clearer.

For those in Coastal Georgia, there will probably be freaking out since GFS shows the storm going offshore from Florida then curving back into the coast late next week. I’m sure someone will create very scary and impressive graphics for that. That is classic profiting from “Fear Uncertainty and Doubt” (FUD). Yes, that is one scenario, but there are lots of others that are just as likely. If you have a hurricane plan, you’re fine. It is time to start watching this storm – especially in Florida, where some precautions will start to be taken late this weekend in places like the Keys that have long lead times. But for coastal GA/SC, it’s worth watching, but nothing to panic over.

A reminder for those who use Facebook: FB is a terrible way to get storm hazard information. For one thing, it doesn’t show you posts chronologically, but by popularity. Another big factor, especially for this blog, is that I don’t pay for either advertising or “boosting”. So FB limits the distribution of these posts. If you want to see these posts the best way is to subscribe to get the blog by email (at the bottom of this page).

Atlantic Update 22 Sept 2022

Fiona will pass by Bermuda tonight, bringing winds up to 90mph, power outages, and some damage. After that it looks to hit northern Nova Scotia Saturday on the current track, and if the NHC intensity is right, winds upwards of 100 MPH across Cape Breton Island. This is a track shift south a bit from yesterday. Here’s the forecast damage swath with “plain language” impacts:

click any image to embiggen.

So Atlantic Canada should expect a big blow this weekend.

The tropical wave that has the weather doomers excited (invest AL98) has passed the windward islands and has entered the far south-east Caribbean. Conditions there are not too favorable, but by the time it reaches the central Caribbean conditions are likely to be better and a tropical depression or storm should form this weekend if not sooner. The global models still bring the storm over the Yucatan straits or western Cuba, but after that there is some dispersion. Some (such as the 00z European model) take the storm across Florida, but GFS keeps creeping west. I again warn that model forecasts for a storm that doesn’t even exist yet are notoriously unreliable, especially at the 5-10 day outlook range. So while it provides endless fodder for people who desperately need you to click and watch, it’s not really productive for you. Here is the current dispersion map (a measure of forecast position uncertainty) … as can be seen, even at 5 days (120 hours) it’s pretty broad:

Bottom line: AL98 is going to cause rain and maybe some gusty winds across northern Central America (Venezuela, Columbia) and the ABC islands (Aruba, Bonaire, Curacao). Beyond that, we’ll just have to wait and see.

Invest AL98

There are two active storms in the Atlantic, Hurricane Fiona (NHC Key Messages regarding Hurricane Fiona) should pass close enough to cause moderate impacts to Bermuda before making landfall in the Canadian Maritime provinces Saturday Night/Sunday. The US East Coast will see dangerous rip currents from its waves this week. Gaston may be best, and the rest all drips, but Belle knows that as a tropical cyclone he’s never going to be much of a hurricane, limited to annoying the shipping industry and perhaps some minor impacts to the Azores. Here are the swaths …

click to embiggen.

But there is an invest area that has those who profit from weather paranoia most excited, so let’s take a closer look at AL98, a disturbance approaching the southern Caribbean. NHC’s five day outlook has it tagged with a 70% chance of becoming a depression in the next two days, and a 90% chance by this weekend. Here is what some of the models are showing as a track this morning:

raw spaghetti, cook before consumption.

For the Windward Islands, most likely it will just bring some gusty winds and rain. After that, conditions in the central and western Caribbean as well as Gulf of Mexico are forecast to be pretty favorable (if #1) so if it follows a track that takes it into the Gulf (if #2) it could develop into a significant hurricane. The models have been showing a fairly wide spread as shown in the above track map, but recently they have converged a bit. Here is a snapshot of the GFS (orange), ECM (European, cyan), and CMC (Canadian,green) models for a week from Tuesday Evening (28 Sept 2022). All show a hurricane near the Yucatan Straits.

click if you dare.

Both the GFS and ECM show a significant storm hitting Florida in about a week – ECM south Florida (south of Sarasota), GFS on the panhandle. BUT THE MODELS ARE NOT RELIABLE THAT FAR OUT! There is a reason that NHC doesn’t do seven to ten day forecasts, especially for storms that don’t exist yet! Yes, it is a little concerning the model runs have become more consistent, but we have seen that before and then nothing happens. If you have a hurricane plan, (you DO have one, right?) there is nothing to get excited about. Assuming something spins up there is plenty of time to see if those two big ifs materialize, and the storm does track towards the US, to then do something about it. In the Caribbean definitely need to be watching, but for the US, will be a couple of days before anything solid can be said.

Watching #Fiona notes

Since we have a storm that might look like it’s going to impact the mainland US, just a reminder that I don’t normally do rapid-fire, ZOMG THERE’S A NEW MODEL RUN OR FORECAST! LOOK AT ME! kinds of posts. Usually I do a big post in the mornings, and only post updates during the day if there is a significant change. Seriously, it’s just not worth the stress, these things usually don’t change that fast.

click to embiggen the 11am satellite image and NHC storm overlay.

But since I’m here, nothing much changed with the 11am NHC forecast. Slight track shift, maybe some potential for a stronger storm after it exits Hispaniola (Dominican Republic), but no significant change in the guidance this morning. If you’re not in the northern Caribbean or (as of this morning) southern Bahamas/Turks and Caicos, no need to do anything or freak out just yet unless you need the exercise. If you are in those places, follow the NHC and local guidance for tropical storm warnings. Tropical storm conditions will hit the Leeward Islands this afternoon, and spread across the Virgin Islands (US and British) and should reach Puerto Rico tomorrow afternoon or evening.

I just heard on the radio news again that Fiona “may threaten the US.” Well, if you mean pass by hundreds of miles offshore, then sure, that’s the current scenario (as noted this morning). It will probably brush the southern Bahamas then head towards Bermuda. Worth checking in Saturday, Sunday morning at the latest to see if that’s changed, but otherwise be chill 😛 (can’t believe I wrote that).

Those of you who watch the NHC Tropical Weather Outlook will note a couple of disturbances in addition to Fiona, but they both are currently of low chance of formation (20% or less). No need to worry about them right now.

#Fiona Friday

Although NHC found stronger winds, Fiona is still a very sheared system this morning. Here’s the TAFB analysis, notice the center of circulation (the tropical storm symbol) is still on the edge of the dense clouds, and there is a lot of dry (orange) air in the storm:

Click for detailed view.

Other than a stronger storm, nothing much has changed since yesterday except the longer range model guidance is more consistent. Here is this morning’s model dispersion analysis, which shows where we would expect the storm to end up based on the major global models:

So the NHC forecast is for a bit stronger storm, and shifted a bit south and west, but not terribly different from yesterday. Here are the Key Messages regarding Tropical Storm Fiona. And here is the latest damage swath using my TAOS/TC model, based on the 5am ET official forecast:

click any image to embiggen.

On this track the storm will likely cause a fair amount of impacts across the leeward islands, Puerto Rico. Power outages, roof damage, and in steeper terrain mudslides and flash flooding are all likely. There are over 12 million people in the damage swath, mostly in Puerto Rico and the Dominican Republic. Damage could approach $1 Billion if the storm maintains intensity, as the official forecast (supported by the models) shows.

Beyond the NHC forecast (which, I again remind everyone, the NHC forecast is the only thing you should be using for decision making unless you have very specialized needs and expert, site specific advice) it looks like the storm will turn out to sea and parallel the US East Coast. Unlike yesterday, the modeling is pretty consistent showing that. Of course since the track is pointed towards the US, it will give the chattering class something to talk about, and the infamous Cone of Shame might fall close to or even touch the coast next week. While the southern Bahamas are within the potential threat area, as noted yesterday at the moment the mainland US isn’t under direct threat, given the meteorological setup. So if in the Caribbean, definitely move forward with taking protective measures and monitor the NHC site (updates every three hours at this point) and check local news updates regularly. For the mainland US, still no need to get excited, check back in tomorrow or the next day.

Tropical Storm #Fiona: Where, How Bad?

As expected the tropical depression approaching the northern Caribbean got organized enough last night to be designated as Tropical Storm Fiona. Given it’s somewhat pointed towards the US, there is much rending of garments and gnashing of teeth, so let’s take a closer look at what we know (and more importantly don’t know and should probably just shut up about 😛 ).

We start of course with the NHC’s Key Messages regarding Tropical Storm Fiona (no Spanish version up at the moment). Here’s my TAOS/TC model impact swath based on that forecast:

click to embiggen.

Tropical storm watches are up for the northern Leeward Islands including Antigua, Barbuda, St. Kitts, Nevis, Montserrat, and Anguilla, Sint Maartin, Saba and St. Eustatius. On this track it will bring tropical storm conditions to the Virgin Islands and Puerto Rico late this weekend, with the biggest risks being flash flooding and mudslides. NHC will probably start raising watches later today. In the current forecast Fiona isn’t expected to become a hurricane, and should remain a moderate tropical storm at worst. Still, there are nearly six million people in the damage path, and some of the infrastructure is vulnerable so a couple hundred million dollars in economic impact is expected. I would call this hazardous, but not dangerous if proper precautions are taken.

Conditions are not great for this storm. Here is the surface analysis from the Tropical Analysis and Forecast Branch (TAFB):

TAFB analysis over GOES Water Vapor image

In this map, orange is dry air. Notice that the center of Fiona (lower right) isn’t embedded within the wet (gray/blue/green/red) air. This is due to wind shear, and the dry air is being “entrained” into the circulation. This inhibits development. Something else to look at in the longer term is the front draped across Florida and running offshore of the southeastern US (and note over Georgia South Carolina the very welcome cooler, dry air to give us a break from the recent extended rains). That is important as the storm approaches and passes Puerto Rico/Hispaniola. Notice on the NHC track forecast (and TAOS swath above based on their forecast) has a northward bend in it. This is due to a change in the steering currents (mid level winds) associated with that front and the dome of high pressure over the mid Atlantic. So, what does all that mean for the track and intensity? Here is a map that can help with that first part …

This map shows a few of the major objective (computer) track models, with ellipses showing the dispersion or scatter at various time frames. Out to 96 hours the forecasts are pretty good – in fact, when compared to historical forecasts, it’s even “Excellent” at 72 hours (three days, when the storm should be approaching Puerto Rico. But look what happens at five days: the ellipse is yuge and dispersion is “Poor”. That’s because at that point the storm will be encountering that front and associated winds. Some of the models (like GFS) show the storm stronger and sneaking through the front, others like the Canadian Meteorological Center model show the storm remaining sheared and persisting as a weak system across Cuba. For intensity, here is a plot showing the intensity forecasts for the next five days. Only one model shows Fiona becoming a hurricane – and it’s almost always on the high side the last few years.

The NHC forecast splits the difference between the GFS and European Met Center model. For planning purposes of course you should use the official NHC track, and not worry too much what happens after that because of the uncertainty. At this point any speculation about impacts on the US are just that: pointless speculation at best, spreading FUD for fun and profit at worst. While it’s too early to say for sure, impacts to the US aren’t terribly likely given the meteorological setup but if the expected turn to the north doesn’t materialize there is plenty of time to see it and do something about it. Unless you live in the northeastern Caribbean or Greater Antilles, there’s no need to wear out your refresh key, check back tomorrow morning …

Atlantic clear, West Pacific busy

TLDR: Nothing threatening in the Atlantic. Tropical Storm Kay recreated a famous song from the 1970’s. Typhoon Muifa may disrupt shipping off of Shanghai and cause some damage in China. Details if you are bored, have interests in the West Pacific, or buy stuff from China …

Tropical Analysis, Sunday Morning 11 Sept. Earl in upper left, remnants of Kay middle left. vast expanse of boring in the tropical Atlantic. Click to embiggen.

Earl has transitioned into an extratropical cyclone, and is causing some gusty winds across both Bermuda before brushing Vinland (aka Newfoundland).

Yes, it never rains in Southern California, but girl don’t they warn ya: it pours. Tropical Storm Fay set a few records (link to NBC 7 San Diego). So that catchy old 1970’s song makes a lot more sense …

On a more serious note, Typhoon Muifa is moving towards the coast of China and disrupting the major shipping routes through the East China Sea. While it is currently a Category 3 storm, it looks to decay to a Category 1 storm as it brushes Ningbo and Shanghai. Given the vast quantity of containers shipped through that port comples alone (3 million TEUs in May), losing another few days after the loss of a few days from Hinnanmor is extremely disruptive. To put that volume in perspective, the Port of Savannah has been handling around 500 thousand TEU/month this year, pre-covid Los Angeles/Long Beach were about 1.5 million TEUs. (A TEU is a twenty foot equivalent unit – click for Wikipedia explanation). China moves about 24 million TEU/month out of the global total of around 66 Million. So when shipping traffic around China is disrupted, it’s a big deal …

Storm Updates

Lots going on, but at the moment the only significant threat to land is Hurricane Kay, off the coast of Mexico. it looks to brush Baja before turning out to sea. That might bring some gusty winds and rain to the San Diego area … here’s what NHC has to say: Key Messages regarding Hurricane Kay and here’s my TAOS/TC model showing possible conditions …

In the Atlantic, it looks busier than it is. The only storm of any concern at the moment is Hurricane Earl, which has turned northward and may brush Bermuda. Key Messages regarding Hurricane Earl (en Español: Mensajes Claves). Danielle is still a Hurricane, still pretty far north, and looks to do a loop before heading to Spain and Portugal, where they can certainly use the rain. The invest area AL95 is nothing to worry about. Assuming it develops it should hit an unfavorable area and decay before bothering anybody …

Click any image to embiggen.

In the West Pacific, a new typhoon is developing that may threaten Taiwan, China, Korea and Japan in a few days. It’s just a depression at the moment (WP14) but conditions are favorable for another strong storm …