“Tropical” Storm #Odette, other disturbances

Here’s the morning surface analysis from TAFB (the Tropical Analysis and Forecast Branch, within the National Hurricane Center) over the GOES IR satellite image …

click to embiggen.

The two features of interest are “Tropical” storm Odette, and the disturbance approaching the Leeward Islands(lower right, above the word “Surface” in the label). I put Odette’s title in quotes because Odette isn’t really very tropical – and despite having some areas of tropical storm force winds, it’s really more like a nor’easter in structure and impact. It will be bringing wind and rain to the Canadian Maritime Provinces, especially Newfoundland (more properly, Vinland). To quote from the Environment Canada forecast

This storm is expected to behave more like a strong fall storm with northerly winds and heavy rain. A cold front moving over Newfoundland on Sunday will interact with Odette's moisture to enhance the rainfall over southeastern Newfoundland later in the day Sunday and Sunday night. A special weather statement is in effect for eastern Newfoundland for Sunday into Monday. There will be some minor influence in Nova Scotia's weather with gusty northerly winds on Sunday. Gusts could be near 70 km/h or so in Cape Breton which may cause some minor issues. Some enhanced rainfall is likely over eastern Nova Scotia Sunday morning as Odette interacts with the cold front.

Odette is another example of a storm that needs advisories, but doesn’t quite fit our current system of “tropical gets one kind of advisories, other storms get something different.” Why does this matter? It’s inconsistent for one thing, and confusing in that a 50 mph wind and coastal flooding from a nor’easter has a different warning structure and, especially in the commercial weather media world, different level of reporting and attention.

On the science side it can cause problems as well, especially in the popular mindset. As data has become better, and marginal storms are tracked and named, there is an impression that tropical cyclones/hurricanes are more frequent. It is true that storm characteristics seem to be changing (almost certainly due to human driven climate change), but you have to be careful with the numbers game because the metrics haven’t been consistent over time. Simple storm counts and trends aren’t diagnostic when it comes to climate change. That’s not a criticism of NOAA or the Hurricane Center – they are doing their job, which is to issue watches and warnings, and over time they have continued to get better and better at it. But people who use that data for other purposes need to be very careful. Which brings up the insurance world.

At least in the US, how something is named and warned has a direct impact on things like insurance deductibles, and the same damaged roof could cost a homeowner $500 or $5000 depending on how the contract handles the “named storm deductible.” After the huge industry losses in the late 1980’s and early 1990’s due to earthquakes and hurricanes, rather than design a rational system the insurance industry successfully lobbied state regulators to allow them to have separate “catastrophe deductibles” for these major events. So US consumers face a bewildering array of contract conditions depending on the hazard or if a storm is named or not. You get crazy things like if your roof is damaged and water leaks in and damages your carpet, it’s covered by private insurance. But if that same rain backs up because of a drainage problem, enters your house and ruins your carpet, it isn’t covered unless you have separate, Federally sponsored flood insurance from FEMA. Even outside the US things like reinsurance contracts and parametric insurance depend heavily not on the actual impacts or damage a storm produces, but how it is classified and if it is named or not. It’s a dumb system – insurance triggers should NOT be tied to a watch and warning system. That just isn’t what it was designed for. End of rant.

For the US, it looks like the impacts of Odette will be limited to high surf and rip currents; there are no watches or warnings at this time. As for the disturbance off of the Leeward Islands, it may briefly become a tropical system, but isn’t likely to last long once it starts its northward curve. As the Tropical Weather Outlook says, people there should “monitor” until it is safely past …

Atlantic Update 17 Sept 2021

Nothing has really changed that much, the remnants of Nicholas continue to be a flash flood risk along the TX/LA coast. There are three disturbances on the NHC Tropical Weather Outlook. Here is this morning’s TAFB analysis map on the GOES East Infrared view (I added the red labels for the three disturbances discussed in the TWO) …

of course it can be embiggened.

From right to left (east to west), the one in the Cape Verde islands (NHC DB3) is ignore-worthy. The other two both have 70% chances, but that’s the chances of becoming a tropical depression or storm, not the chances it will kill you. The one in the mid-Atlantic, DB1 (AL952021) has the “magic words”:

... a tropical depression is still likely to form over the weekend or early next week while moving toward the west-northwest at 15 to 20 mph across the central tropical Atlantic and then near or north of the Leeward Islands by Monday and Tuesday. Interests in the Leeward Islands should monitor the progress of this system during the next few days.

So if you’re in the Leeward Islands, monitor it, and be ready to act if something untoward happens. Not in the Leeward islands, don’t worry about it. The global models aren’t doing much with this one; GFS has it taking a sharp right turn as a disorganized low (not even a depression).

The disturbance just off the US coast (NHC’s DB2, AL962021 in the ATCF ID’s) may also briefly become a storm. After pointing out it is disorganized and elongated, NHC goes on to say …

... this system is still likely to become a short-lived tropical depression or tropical storm before it makes a transition to a non-tropical gale-force low by Saturday or Saturday night while moving northeastward at about 15 mph away from the United States mid-Atlantic and Northeast coasts. Regardless of development, this system could bring high surf to portions of the mid-Atlantic and Northeast U.S. coasts and Atlantic Canada through this weekend.

So beware rip currents this weekend.

Where did it go? (Update for 16 Sept 2021)

To reinforce what was said (repeatedly) over time about models and people who get excited about long range forecasts, take a look at this comparison of the GFS 850mb winds from runs at 00z yesterday and today, for Friday the 24th at 8pm:

Swipe left to see current forecast (no storm), swipe right to see yesterday (with storm)

So the various blogs and weather channels that spend a lot of time talking about this stuff are potentially getting you worked up for nothing and wasting your time (well, they are making money off of your fear and angst, but that’s another story).

Most invests and disturbances don’t ever become anything, and even a high formation probability can quickly drop to zero, just as one with a low probability can quickly spin up. Those odds are as much art as science. In either case, as I so often point out, no matter what anyone is saying, if the NHC Tropical Weather Outlook does not have the magic words “Interests <somewhere> should <do something>”, or if it does and you aren’t <somewhere>, then please don’t worry about it and switch off anyone who says you should. The same applies to a live storm – no mention of your area in the “key messages” graphic, no need to worry.

Here’s the current view of the situation in the Atlantic. The remains of Nicholas are still dumping rain in the US South, there is a system off the US East coast that will be generating high surf (and rip currents) across the coast, but if it spins up looks to stay offshore. NHC sent in an airplane yesterday – it didn’t find anything – and will do so again today given how close it is to the US coast. As for the thing off of Africa (AL95), satellite data isn’t showing significant development yet, but it does have potential to become a tropical cyclone. Here’s the TAFB situation map for the Atlantic this morning:

Click to embiggen;

Chanthu is slowly moving away from the China coast off Shanghai, and will be sweeping across Japan as a weakening system. Mostly a rain threat at this point. Elsewhere it’s fairly quiet for this time of year …

If you aren’t familiar with weather maps and symbols, here is a video primer (link) from the Univ of Illinois, and a web primer from NOAA (Link).

#Nicholas, #Chanthu and #China ports, Atlantic watch Wed 15 Sept

TLDR: Nicholas continues to dump on the Gulf Coast, Shanghai/Ningbo starting to reopen, and why you shouldn’t get excited about models episode eleventy-billion or something.

Nicholas is still being tracked as tropical depression. By far the biggest impact of this thing has been rain and ongoing flooding along the Gulf Coast. Here’s the forecast rain swath for the next few days as the remnants drift east …

click an image to embiggen.

Tropical Storm (formerly Chanthu) is wrapping up it’s S turn off the coast from Shanghai and is headed towards Kyushu (the southernmost main island of Japan) as a tropical storm. It will bring rain across Japan over the next couple of days, but winds should remain well below hurricane (typhoon) intensity. Operations are starting to resume in the ports of Shanghai and Ningbo, which is important as these two port are responsible for over 10% of the entire world’s container traffic. A three or four day disruption may not sound like much, but a four day outage equates to around one million TEU’s of disruption in traffic, which has a rippling effect especially given the already messy situation in global shipping.

NHC is watching a couple of disturbances in the Atlantic. One, off the US East coast, might move north and impact North Carolina and points north as a tropical system. The usual suspects seem excited about AL95, the disturbance off of Africa. The last couple of GFS runs have it spinning up in to a fairly organized/intense system, but the intensity and track have a lot of uncertainty. Here is a comparison using the cool slider thingee function in wordpress, showing the 00z and 06z runs, forecast for Friday night about 10 days from now (the 24th). Grab the <> thing and slide back and forth to see the difference …

Comparison between 00z and 06z GFS run forecasts for 8pm Friday, 24 September 2021

That’s actually pretty tight, but reinforces the fact that any speculation as to who (if anyone) is doomed based on this kind of thing is pointless. I can’t say this enough: until the hurricane center uses the magic words (“interests <somewhere> should <do something>”) in their outlooks or advisories, please don’t stress out over it. If you have a hurricane plan then you’re fine – it’s 5 days from the leeward islands, and nearly two weeks away from the US even if it does spin up (which is likely but not certain yet) or come this way (which is very uncertain – a track offshore is more likely). And to the media people: stop with the fear mongering. Recall the fable of the irresponsible kid and the wolf who heroically ended his reign of terror …

#Nicholas hits #Texas, #Chanthu blocks #Shanghai/#Ningbo

NHC upgraded Nicholas to a hurricane just before landfall, based on an isolated hurricane wind report. In reality that’s just a technicality, the impacts were that of a strong tropical storm, and the major threat continues to be inland rain and flooding. In the Pacific, Typhoon (now tropical storm) Chanthu missed a landfall at Shanghai, but has spent the last day doing a slow “S” turn just offshore from Hangzhou Bay …

modeled Wind Waves off of coast of China; click to embiggen.

This matters a lot because two of the three largest container ports in the world are blocked by the storm: Shanghai, that last year moved over 43 million TEU (Twenty foot Equivalent Units), and Ningbo, that moved almost 29 million TEU. The storm is likely to disrupt traffic for a total of for or five days. The impact on global supply chains is significant – these two ports combined move an amazing 10% of the world’s container units (73 million TEU of the global total of 775 million last year).

Back in the Atlantic, there are a couple of disturbances but none are a threat in the immediate (5 days) future and beyond that, well, there isn’t much skill in forecasting that so don’t worry about it. As a reminder, if the magic words “Interests <somewhere> should <do something>” don’t appear in the hurricane center’s Tropical Weather Outlook, ignore what any sites or media outlets are saying about them.

Tropical Storm Nicholas

The disturbance in the Gulf of Mexico has gotten organized enough for NHC to start advisories and tracking as Tropical Storm Nicholas. Right now it looks like the Texas coast is in the damage swath and tropical storm warnings are in NHC’s Key Messages regarding Tropical Storm Nicholas (en Español: Mensajes Claves). Here’s my TAOS/TC damage swath estimate:

Click to embiggen.

Like many of the storms this year, rain will likely be the biggest threat, with some of the forecasts showing up to a foot of rain on the Texas/Louisiana coast in the next week:

There are several disturbances in the Atlantic, but not are a worry right now.

In the Pacific, Typhoon Chanthu passed just offshore from Taiwan, limiting damage but nevertheless likely caused under a billion dollars or so in impacts with heavy rains and flooding. Next up is the densely populated region near Shanghai, China, where if it continues as forecast will inflict over $4 Billion in impacts and additional supply chain disruptions, especially since it is expected to slow down and turn right offshore, spending nearly 48 hours over Hangzhou Bay and pummeling ports and delaying shipping. Shanghai is the worlds busiest cargo port, Ningbo is number three …

Needless to say, the real Nicholas isn’t really excited about this as it means the office will be busy and it will detract from his being the center of attention.

Tsar Nicholas the Cat, always the center of attention.

Tropical Depression #Mindy, Hurricane #Larry, Typhoon #Chanthu and #Taiwan, #China

The National Hurricane Center started advisories on Tropical Storm Mindy last night. It’s a very minimal storm, mostly a rain event, and a very asymmetric one at that with the heavy rain displaced to the northwest of the storm. Here’s the radar composite at 5:18am this morning …

click to embiggen.

For those in Coastal Georgia and South Carolina, this should be a non-event relatively speaking. Some potential for heavy rain this morning and early afternoon, so you might see some street flooding in the usual places (Savannah has a Waters Avenue for a reason 😛 ). But winds should be light outside of thunderstorms, and the tornado risk is only slightly above normal. Key Messages regarding Tropical Depression Mindy (en Español: Mensajes Claves).

Hurricane Larry is speeding towards Vinland (called by the locals “Newfoundland”) and will be causing high winds, rain, and surf this weekend. Nova Scotia might see gusty winds and rain as well

Elsewhere in the Atlantic, NHC has two disturbances tagged, but neither has the magic words so aren’t worth talking about at the moment.

There are other tropical systems out there. Tropical Storm Olaf will probably become a hurricane this morning and swipe Baja del Sur tonight/tomorrow. In the Pacific tropical storm Conson has passed over the Phillipines and is headed towards Hainan Island and Vietnam, may briefly become a typhoon but should decay before landfall Monday.

Of more concern is Typhoon Chanthu. On the current forecast track it should pass directly over Taiwan, and will be passing just offshore from many major port facilities in China. It may stall just offshore from Shanghai. Current economic impact estimates are over $10 Billion USD on this track, with some as high as $18 Billion. Given the fragility of the world’s supply chains, many of which are dependent on the Taiwanese semiconductor industry, and the major ports in China likely and all of the shipping likely to be disrupted on this track, it isn’t a good situation …

#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.