#Mexico Earthquake, #AL91, #Larry

There has been a large earthquake on the Pacific coast of Mexico, a magnitude 7 just inland of Acapulco. The initial model estimates are for damages approaching $4 Billion USD, but damage reports from the region are not extensive so far, with only one death reported.

click to embiggen.

In the Atlantic, Hurricane Larry continues to be a major hurricane, but is expected to remain well east of Bermuda. Despite that, given the large size, Bermuda should expect tropical storm conditions: Key Messages regarding Hurricane Larry. After passing Bermuda it is expected that Larry will begin to transition to an extratropical system as it passes near or over Vinland (Newfoundland), with blustery conditions and rain for the Canadian Marintines. Larry is also causing impacts along the US coast in the form of swells and rip currents, so if near the beach be careful.

The hurricane center is also watching a disorganized low in the Gulf of Mexico. It is encountering the remains of a front that has stalled over the southeast, and is expected to move over the big bend of Florida then exit off the coast of Georgia by Thursday evening. Aside from some heavy rain and thunderstorms, if you weren’t told it was a tropical system you probably wouldn’t think it unusual for a summer storm. NHC gives it a 50% chance of organizing enough to start advisories. Even if they do, nothing much to worry about – even though close to the coast NHC doesn’t bother with “interests should monitor.”

There are now some storms in the Pacific as well – a weak tropical storm is over the Philippines, and a small but powerful typhoon is headed for the South China Sea between the Philippines and Taiwan:

Impacts are estimated at 1.1 Billion, mostly due to the landfall in China, but a wobble either way bringing the small storm over either Taiwan on the PI could greatly increase that estimate, as well as the number of people at risk …

#Larry, disturbance in the Gulf (#AL91) is still a thing (Mon 6 Sept)

Hurricane Larry continues to be a huge storm moving through the central Atlantic. Larry has an eye diameter of over 50 miles – far larger than the typical size of 20 to 25 miles for a Category Three hurricane. Here is a visual band view from about 7am this morning, the storm just finished an eyewall replacement cycle so it isn’t as clear as yesterday:

click to embiggen

The overall picture hasn’t changed much since yesterday. Here is the morning analysis from TAFB, over the GOES East IR image

Hurricane Larry is on the right, being steered by high pressure to the north. It should continue a broad turn to the north, then to the northeast, passing off to the east of Bermuda. The question is how close the large storm will get to the island. As the latest NHC bulletin says (Link: Key Messages regarding Hurricane Larry)…

it is too soon to determine the magnitude of these hazards and potential impacts on Bermuda, interests there should closely monitor the latest forecast updates

Many in the southeast are freaking out over the yellow blob of doom on the latest NHC Tropical Weather Outlook. The disturbance of interest is over Yucatan on the map, the “L” above the label “TRPCL WAVE” across central America. The cold front moving into the Southeastern US (jagged line across Alabama-Georgia-North Carolina) is expected to stall out over the region. The low pressure disturbance should move into the Gulf then cross over the Big Bend of Florida, across south Georgia, then into the Atlantic. It shouldn’t do much until it moves offshore, where it might spin up into a tropical storm. But not really anything to worry about in the deep south other than the potential for enhancing the rain in the Ida impact areas. Beyond that, too early to tell.

#Larry, thing in the #Gulf update (Sunday 5 Sept)

Remarkably quiet around the world today, only one tropical cyclone – but it’s a monster Category Three. Fortunately Hurricane Larry is in the mid Atlantic and not a direct threat to land:

The GOES East one-minute mesoscale sector scans have been producing some remarkable views …

click to embiggen.

NHC has started posting Key Messages regarding Hurricane Larry. Bermuda should be paying attention, as it is within the possible impact swath if the storm goes west of the forecast track. In addition, Larry is generating swells (waves) that are propagating across the Atlantic and starting to reach land, which can present a significant rip current hazard. TO quote from the discussion:

 Large swells generated by Larry are expected to reach the Lesser Antilles today and will spread to portions of the Greater Antilles, the Bahamas, and Bermuda on Monday and Tuesday.  Significant swells will likely reach the east coast of the United States and Atlantic Canada by midweek.  These swells will likely cause life-threatening surf and rip current conditions, and beachgoers and other interests along these coasts are urged to follow the advice of lifeguards and local officials this week.

Elsewhere, the thing in the Gulf (AL91) is still tagged with a 30% formation chance in the next five days. It’s not really expected to be a significant threat as a tropical system, but it could bring some rain, hot humid air, and winds to the Louisiana coast – which really doesn’t need it right now. No significant threat to the rest of the Southeast.

Hurricane #Larry, watching the #Gulf

Hurricane Larry is almost a Category Four storm, but isn’t a threat to anybody other than creating a lot waves (swell) than will be causing rip currents in a few days …

Infrared (cloud top temps) on the left, Visual on the right. Click to embiggen

On the left of these images, over Yucatan, is a tropical disturbance that will be entering the Gulf of Mexico. It’s a concern not so much for development (30% according to NHC this morning) but because it will likely bring more misery in the form of rain and humidity to Louisiana next week.

#Ida continues to cause damage, #Larry the cable guy

The remnants of Hurricane Ida (now a “Post Tropical Cyclone”) continues to cause damage across the US Northeast as it finally moves offshore. That, combined with the ongoing power outages, is increasing the economic impact total for the storm, which is now probably over $55 Billion USD and moving Ida into the top five storms in US History.

Hurricane Larry continues to develop in the eastern Atlantic. While it may be a factor for Bermuda and trans-Atlantic shipping, it’s mostly a Cable TV news/weather channel storm. Why is that? Here is this morning’s surface analysis map from the US Weather Service’s Tropical Analysis and Forecast Branch:

TAFB map of the Atlantic, Thursday 2 Sept 2021. Click to embiggen.

In the upper right is an “H” indicating a big high pressure system. Air circulates clockwise around high pressure in the Northern Hemisphere. That is pushing the storm at first west, then it should turn northwest then to the north and northeast as it rounds that mound of air. That, combined with the projected interactions with surrounding systems like the cold fronts headed to our coast (jagged line across the eastern US) should combine to keep the storm offshore.

Here’s the infamous “spaghetti map” of tracks generated by the various computer models. As a reminder, the colored lines are the primary track models – the “cloud” of gray lines are mostly ensemble members – alternative scenarios, many of which are not realistic, but are generated to provide context and probability. Remember the pasta must be cooked before eaten …

Computer model tracks (and NHC track in red).

The longer term models (such as the GFS and EMC) both take the storm well off shore longer term. So again, your best source of information on hurricane threats for a live storm are the National Hurricane Center’s “Key Messages” summaries. In the case of Larry, it’s no threat land so there aren’t even “key messages” at this point, so you’ll have read the public advisories.

Atlantic Storm Watch (#Ida aftermath, #Larry)

First a bit of good news, it seems the critical LOOP oil terminal survived hurricane Ida, and while there will be weeks of recovery ahead, the oil and gas infrastructure does not seem to have suffered any critical damage. The bad news is that the electrical grid is in shambles, which will slow down recovery (including getting the refineries back online). Worse, it will be hot and muggy the next few days; the entire disaster area has high heat warnings today …

Heat (HT) and Flash Flood (FF) warnings, Wed. morning. Click to embiggen.

Elsewhere, in the far eastern Atlantic tropical storm Larry has formed. Like Ida it is headed for an area ripe for rapid intensification, and is expected to be a major hurricane within three days. Fortunately, it should turn north and stay well away from land (those in the US shouldn’t freak out it seems to be curling towards the US in this map, it’s an artifact of projecting the globe on a flat map, and Larry is *way* out there!). There is also a new invest area in the Caribbean (AL91). Development over the next five days is currently projected at 20%, but it’s in a scary place given Ida’s track, but more than likely it should drift west towards Central America as a weak system.

Tropics overview, #Ida impact notes

Ida is raining out over Mississippi/Alabama/Tennessee, still causing flooding and impacts across the south …

Surface Analysis and Radar Composite, Tuesday morning 31 August 2021.

The remnants of Hurricane Nora are also causing flooding in the southwest – it’s the blob of rain over Arizona, having made landfall in Mexico and causing about 300 million in impacts. Elsewhere, Tropical Storm Kate is in the mid Atlantic, due to move north and dissipate. Likewise, a tropical wave (INVEST AL90) following behind it will probably become a named storm, but will also likely follow the same track and not bother anybody but fish and shipping.

Ida’s economic impacts continue to rise. When looking at economics it’s important to be clear what you mean. The storm probably caused about $28 Billion in damage in terms of simple direct physical damage value. There are some big unknowns – while it appears several key refineries avoided damage, yesterday a flood control structure failed and one refinery was flooded. And there is no word yet about the vital Louisiana Offshore Oil Port (LOOP) and its onshore support equipment. That alone could have huge ramifications both directly and indirectly.

Another big issue is that things are rarely rebuilt exactly as they were – for one thing, construction codes change over time. As one example, there are regulations that say that if a structure is more than 50% damaged it must be rebuilt to meet new flood zone codes, which can cause a home that would have cost $100,000 to repair or replace to cost $300,000 or more to rebuild. Delays can also cause damage to increase, as well as increase secondary impacts like lost wages. For example, if power is out and supplies slow to reach an area, additional damage can be inflicted from even relatively mild follow-on rainstorms. Secondary economic impacts are even more tricky to compute, and depend heavily on the decisions make by local, state, and federal authorities, as well as the “hidden hand” of the economy and investors. Demand inflation is often a factor – when supplies are short, prices go up. And while regulators try to prevent it, price gouging and opportunism sneak in whenever they can.

When you put all this together, the current estimates for Ida are in the $45 Billion range. It could rise as high as $60 Billion depending on the unknowns like the oil and gas infrastructure that has yet to be surveyed, how long the power stays out, and what regulators and officials do. A final issue is what Congress does. The Hurricane Sandy relief bill included money for salmon farms in Washington State, all the way across the country from where the storm hit! That and other pork are often included in the Sandy numbers, and the Katrina impact number often includes $20 Billion in mitigation spending (which, while obviously needed, should have been spent before the storm: it wasn’t caused by the storm). So the price gouging and opportunism (and when we’re lucky needed improvements) that follows storms like the mosquitoes sometimes wears fancy suits and has high end offices on K Street

#Ida Landfall recap

Ida is now a tropical storm, decaying inland over Mississippi and dumping rain across the region. The remnant low is expected to track across the southeast then back out to sea after crossing New Jersey, regenerating somewhat. Here’s the “big picture” for the track, along with two other storms we’ve sort of been ignoring (Nora, which caused several hundred million of damage in Mexico, and TD 10, which is a fish storm):

And here is closer view of the Ida impact zone:

With the coming daylight the damage assessment for Ida can begin. Fortunately so far only one death has been reported. As for damage, at this point all we have are models. The direct damage models come in at $25 to $35 billion, but the more complex models give economic impact totals in the $35 to $50 Billion range. It’s almost certain that when all the damage is tallied up Ida will be in the top ten, and likely in the company of storms like Andrew (#6, inflation adjusted $48 Billion) and Ike (#7, at $38 Billion).

A lot of the uncertainty hinges on damage to two essential elements of the nation’s energy infrastructure: the LOOP terminal, and to the onshore refineries. These are multi-billion dollar facilities with obviously widespread economic ramifications if they are severely damaged and offline for months. The LOOP terminal is a vital conduit of oil into the refineries, and the only deep water port than can handle supertankers. It, along with the onshore facilities at Port Fourchon, were in the direct path of IDA and no doubt suffered significant damage. As for the onshore refineries, unless something broke that shouldn’t have, there may be some good news. The swath of heaviest damage seems to have only passed over or near few refineries. The Marathon Ashland Garyville refinery (565,000 BPD) may have suffered significant damage, and the Valero Saint Charles Refinery (340,000 BPD) and Shell Noco were also very close to the eyewall damage swath. Here is the MRMS mid level rotation data for the last 24 hours with the NHC track line. It’s a bit noisy, but you can see the parallel bands of the eyewall as it comes ashore (right over the LOOP) then turns northward as the storm decays near the refineries mentioned above:

Fortunately the eye wall missed the core of New Orleans. That doesn’t mean there won’t be enormous damage, especially as one moves to the western suburbs. And given the widespread power outages, and the potential for pump failures (which should be running on backup power, but some are offline) there may be flooding inside the flood control systems due to the rain. There were also a few levee failures outside the city that have cause flooding.

I heard the governor of Louisiana say this was a worst case scenario – that’s simply wrong. As bad as this may turn out to be it was in reality a near miss … it could have been a lot worse.

#Ida: the wobbles will matter for #NOLA (11am Sunday Update)

Ida is a category four, nearly a category five storm with winds just below the threshold (150mph, 155 is the lower limit for a cat five), and should make landfall in the next few hours. The 11am NHC update didn’t change the track or intensity much, so the post this morning on potential impacts is still valid (link). In that post I noted that small track changes can make a huge difference, especially for storm surge. The core of Ida is actually small – especially compared to Katrina – so while this is going to be bad, it’s possible that downtown New Orleans may avoid a total catastrophe. Let’s take a closer look …

First, recall how wind blows around a hurricane. Here is the wind flow around Ida from this morning as it approaches the coast:

Wind flow around Ida (from GFS model). Click to enlarge.

Air flows around a storm counterclockwise in the Northern Hemisphere, and is strongest in the northeast quadrant of the storm due to storm motion as well as Coriolis forces. So in general, the water piles up on the right hand side (facing the direction of motion) because the wind is blowing it towards shore; on the left, the winds are blowing offshore and can actually blow shallows bays and shorelines dry! Since the Gulf Coast faces south, this means that in general the peak storm surge will be to the east (right) of the landfall location. So far so good.

But New Orleans is very different because its most vulnerable shoreline is actually on the North side of the city! That’s because the city is in between the Mississippi River (with its tall natural and artificial levees) and Lake Pontchartrain – a great place for storm surge with its long, shallow fetch. Let’s start with the forecast track (which is virtually identical to the 5am track):

Surge if storm follows forecast track (click to enlarge).

On this track, which remains the most likely scenario, it would likely cause around $45 Billion in damage, with the eye wall passing through the western suburbs of New Orleans. Notice that as expected the surge on the coast is to the right, the storm surge in Lake Pontchartrain is pushed into the west (left) side, and causes minimal flooding in urban areas. On this track water from the Gulf (Lake Borgne) isn’t pumped in to Pontchartrain since Ida is too small to put high enough winds on that side. Now let’s shift the track 30 miles east (the diameter of the eye):

Same intensity, just shifted the track right (east) 30 miles …

Now the eye wall passes over downtown New Orleans, and there is a lot more wind damage, so the total jumps to at least $52 Billion. Notice too there is a lot more water in the lake, but fortunately it mostly ends up on the north side (well, for NOLA, it’s unfortunate for Covington). Now lets shift the track another 20 miles (in other words, 50 miles to the right/east of the expected track):

Same storm, shifted 50 miles from the expected track.

Ut oh. Wind damage in the city has actually decreased. But now the storm surge has shifted to the bottom of the lake, because the winds during eye passage are blowing south. Extra water from the Gulf flows into the lake and south, the levee’s get topped, water ends up in the city, and damage more than doubles due to flooding, probably over $125 Billion.

So now you know more than at least three CNN meteorologists who keep getting this wrong 😛

At the moment it looks like Ida is still tracking towards Houma, and won’t start the northward turn in time for the eyewall itself to sweep over downtown New Orleans, much less pass just east of the city and produce our nightmare scenario shown above. Here’s the latest radar loop (11:50am). Let’s hope it stays that way – the next few hours will be nerve wracking.

Radar from Slidell, LA, 11:53am Sunday 29 August 2021

Hurricane #Ida pre-landfall analysis for #NOLA, #LA

Long time followers know I’m usually one of the few voices saying “this is hyped and won’t be so bad.” Not this time. Sure, CNN got the meteorology/hydrology wrong, and many of the other media are rather unseemly in their excitement, but this is a dangerous and devastating storm, and things are potentially dire for New Orleans (NOLA). Here’s the increasingly bad news. First, the storm itself. As expected, Ida moved into an area nearly perfect for rapid intensification, and the only potential inhibitor, some dry air to the south, stayed out of the circulation. It is now a mature Category Four hurricane, and is likely to stay that way up to landfall late this afternoon.

Ida is now within range of land based radars. Here is the view from Slidell, LA (just east of New Orleans) at 5:20am. Any image may be clicked to enlarge. The left is reflectivity (rain) showing the eye and bands (some of the outer bands are already reaching NOLA), the right is the doppler velocity. In the fine print in the upper left hand side of the doppler side of the display is the peak wind speeds – the radar is seeing a peak 121 knots (139mph) at the altitude the radar beam is passing through the storm (several thousand feet).

The forecast shows Ida making landfall just west of Port Fourchon, with the eyewall sweeping across the western suburbs of New Orleans – Kenner, St. Charles, Laplace. Even a small wobble, well within forecast uncertainty, takes the eastern (stronger, right hand) eyewall right across the city. Wind damage is likely to be epic in either case. Here is the forecast swath:

However – on this track, storm surge flooding in NOLA is actually less likely as the storm surge from Lake Pontchartrain should be pushed parallel to, then away from the levees. This is something CNN’s weather people got consistently wrong yesterday; New Orleans is a bit backwards in that the worst case for flooding is with the storm passing just *east* of the city (to the right). Yes, that places the city in the “weaker” eyewall – but it means the winds blow the water directly into the city. I’ll try to do a post on that today. It’s an interesting situation, one that anyone familiar with tropical meteorology risks in the US is well aware of, and it’s disappointing (but not unexpected) that they don’t know that. How likely is that scenario? Unfortunately it’s a lot more likely than it was yesterday. The track has been shifting eastward, and the satellite and radar fixes this morning are right (east) of the forecast track as well. That’s bad as it places the stronger eyewall across the city, resulting in more wind damage – and if it results in a passage just east of the city, storm surge could well overtop the levees. On this track Ida is forecast to be a $40 to $50 Billion dollar storm, just below Sandy for the #5 spot on the US “costliest” list. But a eastward wobble with the eyewall crossing the city (and a refinery or two breaking), Ida could easily be up there with Harvey, and Katrina in the $100 Billion dollar club. If a levee or the pumping system fails, we could well be looking at the most costly storm in US history. Given the disjointed evacuation process (it’s only voluntary in NOLA), it will likely be deadly as well.

Oil and Gas: on this track and intensity, something like 12 to 15% of US refinery capacity will be offline for at least a month. A lot depends on how strong the storm is when it passes over Baton Rouge and the huge ExxonMobil Baton Rouge Refinery. At 520,000 BPD, that one facility represents almost 3% of US capacity. It is in partial shut-down now to prepare for the storm, which is expected to still be at hurricane force as it passes over Baton Rouge. There is well over 1 million BPD of capacity at high risk from this storm. So much depends on how rapidly the storm decays after landfall – and how well the surrounding electrical infrastructure providing power to them survives. That, and you need people to run these things: if the surrounding communities are devastated, even if the facilities survive with minimal damage the workforce will be in bad shape. Here are the major refineries in the swath …

Down at the bottom of the above map is a label, “Louisiana Offshore Oil Port”. That is a vital bit of infrastructure. Through that platform passes over 10% of US oil imports, and its pipelines are connected to the major refineries inland. The offshore facility will be experiencing waves over 10 meters (30ft) and winds well over 120mph in the coming hours. It is likely to be offline for some time.

This is going to hurt at the gas pump for a while.