Severe weather potential in coastal GA/SC

There is a messy storm system crossing the US, and it is reaching the Georgia/South Carolina coast this afternoon. Here’s the 8am radar, and a tornado warning in the BigBend of Florida …

MRMS Radar composite just after 8am ET. Click to embiggen …

As has been the case with these things lately, the focus of the potential for the most severe thunderstorms and possible tornadoes are in South Carolina, right now looks like between Hampton and Charleston, but everybody especially east of I-95 in Georgia and SC should keep their weather radio’s on this afternoon.

West Coast Storms and Hurricane #Rick #Mexico (Sunday 24 Oct 2021)

Only one tropical system of interest, Hurricane Rick (EP17) should hit the west coast of Mexico Monday (more below), but there are two big non-tropical storm systems impacting the US today. Here is the TAFB surface analysis this morning, showing Hurricane Rick off of Mexico, the tangled fronts and low pressure in the middle of the country, and the big Pacific storm system starting to stream moisture into California …

Click to embiggen

Two areas are of concern in the US – the first is in the middle of the country, where a complex system is likely to produce some strong thunderstorms today. But the big Pacific storm (just under the label in the upper left of this graphic) has been getting media attention with the usual breathless headlines like “Atmospheric river, high winds to wallop California and Pacific Northwest” and talk of “Bomb Cyclones.” The terms “Atmospheric River” and “Bomb Cyclone” both have specific meanings and really aren’t necessarily scary or destructive unless you say them in the right tone of voice.

The more accurate term for “Bomb Cyclone” is “Explosive Cyclogenesis.” There is in fact a technical definition, that a storm decreases in minimal surface pressure by at least (24 sin φ/ sin 60°) mb in 24 hours, where φ represents latitude in degrees. I never liked the term “bomb” as being overly dramatic, but it has been in used in meteorology for a long time. They do have the potential to cause a lot of damage – the one approaching the Pacific Northwest has winds of hurricane force and higher. In addition, a second phenomena called an atmospheric river (AR in NWS abbreviations) is setting up over California today. That stream of moisture will drop a lot of rain there, which has the potential to cause flash flooding and over a foot of snow at higher elevations since in combination with the approaching cold fronts (the saw-toothed lines in the upper left of the above map) there will be a big temperature drop because, well, WINTER IS COMING! This year there is another factor, the large burn scars from this year’s wild fires. That means the vegetation that normally helps slow down or hold back rain is gone, so the potential for epic mudslides is present. You can get accurate and relatively drama free (and totally advertising free since you already paid for it!) reporting on all this at the National Weather Service web site (link). The short range weather discussion is always a good place to check for the “big picture” …

Click to go to Short Range Weather Discussion.

For those in Mexico, here is the damage swath expected from Rick:

Click to embiggen

NHC’s Key Messages regarding Hurricane Rick caution that as is typical for landfalls in Mexico, inland flash flooding and mudslides in the mountains are always a risk with this storm in addition to the threat of storm surge and wind on the immediate shoreline.

The Chinese Hypersonic Vehicle Test

(Note for tropics watchers – nothing active anywhere, nothing expected in the next five days.)

There was a surprising flood of media attention over the weekend about a Chinese hypersonic missile test supposedly conducted a couple of months ago …

Hmmm … single source report echoed in multiple places?

So, is this what it appears? Was US Intelligence “surprised”? Let’s see what Bender has to say:

It is unimaginable that there was any surprise over this within the community – if any analyst was surprised, they should be fired. Immediately. In fact, any journalist who did not immediately ask “how is it possible to be surprised by this??” should also be sacked. And any editor who would let such a headline through to distribution without more context and questions should be sacked. While the USIC isn’t what it used to be, it’s not that utterly incompetent, so obviously there is something else going on. Let’s look a little deeper …

Hypersonic weapons systems are a hot topic right now. The phrase covers a lot of territory, from short range anti-ship and anti-aircraft missiles to land attack weapons and ICBM based systems that can hit targets anywhere in the world within minutes. Hypersonic refers to the speed – generally to be considered hypersonic is to fly faster than Mach 5 (five times the speed of sound). At the high end (literally and technically) are a class of vehicles that fly into space and return. These can range from boost-glide vehicles to vehicles that combine boost-glide with supersonic combustion ram-jet engines (SCRAM jets). There are a lot of technical aspects and considerations in how vehicles are designed, and how altitude and velocity are traded for maneuvering, avoidance, and range.

The first hypersonic boost-glide vehicle was designed in … the early 1940’s. The Silbervogel (“Silver bird”) project was part of the advanced weapons development associated with the V-2 rocket development. After the war, the designers came to America and these concepts were used in everything from the X-20 Dynasoar project (one of the sad, great “what if” projects in history) and the Space Shuttle, as well as modern similar projects like the X-37 today. In terms of weapons development, there were numerous cold war era projects with varying degrees of classification that I will leave to the interested reader to Google so I don’t get in trouble. The Soviets and now Russians have developed and tested – and in recent years deployed – hypersonic boost-glide and fractional orbit bombardment systems such as Авангард (Avangard) that are on combat duty, as well as an array of other hypersonic weapons such as anti-ship and land attack missiles (Циркон, кинжал).

What about the Chinese in particular? Well, the DF-ZF boost-glide vehicle was deployed by the Chinese military and declared operational on … October 1st, 2019. Two years ago – with known tests years before that. They too have hypersonic anti-shipping missiles such as the DF-21, which was supposedly operational as early as 2010.

So even based on public information it’s inconceivable any serious analyst would be surprised by the existence of this thing, therefore there is something else going on aside from the obvious fact that the journalists writing the above news articles are clueless and gullible. While the US has had multiple hypersonic weapons projects over the years, there is an impression it has been lagging well behind Russia for some time. The AGM-183A has had testing problems and is not in deployment, while the Prompt Global Strike program also seems (at least in public) to still be mired in development, although the common hypersonic glide body was successfully tested last year.

So, this isn’t really new. It’s obviously a placed leak for some reason, Why? Probably several reasons: First, at least on paper (and probably in reality) the US is behind in hypersonic weapons system deployment. That is in fact a serious strategic problem, especially for the Navy, as it renders most large navy assets (like Carrier Battle Groups) extremely vulnerable. It also has the potential to negate most of the existing anti-missile systems like the Patriot and render close-in defense systems ineffective. So it makes sense to play up the red threat to get Congress to shovel some more money into these programs, after the huge amounts always already shoveled into these programs, hopefully this time to get some practical results.

Second, there is increasing nervousness over the situation with Taiwan, and the potential for China to move to reassert sovereignty over the island. The “correlation of forces” is already pretty unfavorable for the US to be able to defend the island, so again it makes sense to push potential threats to try to get more funding, redirect assets towards the West Pacific, etc.

And globally China is increasingly asserting itself, with projects not only across Asia but in Africa and Central/South America. So as a strategic threat, China is clearly number one.

In summary, this seems to be an incremental test by the Chinese. If it did in fact miss by “two dozen” miles as reported, that is actually a pretty significant failure in many ways. It makes me wonder about the capacity of systems like the DF-ZF, and how advanced their development really is. For the flood of articles to hit the press this way is a clear indication of an agenda. That’s potentially the real story, and it is distressing that the “news” media doesn’t have the depth to see it.

#Pamela not as strong as expected at landfall in #Mexico; #China storm; #Crete earthquake

Hurricane (barely) Pamela is making landfall this morning on the coast of Mexico, with peak impacts forecast to be near Mazatlan. The rapid intensification to category three never materialized – the storm barely made hurricane force – but is still likely to cause significant impacts:

Tropical Storm Kompasu is also making landfall in China as a strong tropical storm …

And there was an earthquake in Crete yesterday that cause structural damage but no reports of injuries:

The weather looks ok for the Blue Origin “New Shepard” launch of William Shatner this morning.

Otherwise things are relatively quiet. Well, aside from that virus continuing to cause problems, the global supply chain on the verge of collapse, several global hot spots on the verge of exploding in to open war. You know, the usual stuff … 😦

Tropics got busy again – sort of (11 Oct 2021)

We’ve now got four active tropical cyclones – three in the West Pacific, and one off of Mexico, along with a couple of low probability disturbances in the Atlantic. Let’s start with the East Pacific (Mexico) since that’s the more serious threat …

Tropical Storm Pamela is expected to become a major hurricane in the next few days before making landfall north of Mazatlán. If that forecast holds it could cause a significant amount of damage. Here are links to NHC’s Key Messages regarding Tropical Storm Pamela, and from the Servicio Meteorológico Nacional.

Click any image to embiggen.

There are three systems in the West Pacific. Namtheun is expected to stay well offshore from Japan. Lionrock has already crossed Hainan Island (China) and is raining out over Hanoi Vietnam today. Tropical Storm Kompasu is crossing just north of the northernmost island of the Philippines on its way to Hainan (who did they annoy?). Of the three it has the most damage potential, but impacts should be less than $30 Million in China.

Saving the least for last, NHC has two disturbances tagged on their Tropical Weather Outlook this morning, both with only 20% formation chances over the next five days. No magic words, but NHC cautions that heavy rainfall is possible across the Leeward Islands, Puerto Rico/Virgin Islands, and Hispaniola the next few days.

In defense of the explorers (#Erikson, #Columbus)

October 9th was Leif Erikson Day, and October 12th is Columbus Day. In recent years it has become fashionable to denounce European explorers, Columbus in particular, with monuments being removed across the country. In my view this is a mistake, creating a false perception of history for short term political purposes, while ultimately perpetuating and aggregating the racial and ethnic divides these actions claim to be trying to heal. OK, now that I’ve angered half of my readers, let’s see if I can annoy the other half … 😛 … but please read on and consider. It’s a long post, but it’s a complex subject.

First, perhaps I’m a bit biased, but in the absence of older records it seems Leifr Eiríksson actually discovered America, rather than blunder into it looking for something else as did Columbus. Leifr heard about a new land from Bjarni Herjólfsson, who had been blown off course and seen it but not made landfall. Leifr bought Bjarni’s boat and deliberately retraced the voyage for the purpose of finding and exploiting that land, setting foot in what is now Newfoundland.

Leifr Eiríksson discovers America …

There are stories of earlier contact from Europe going back to Roman times, but if such contact existed (and it possibly did), they left little trace and no solid records. And of course there were many rich, complex, and fascinating (as well as utterly horrific) civilizations here. I do agree it’s somewhat dismissive to imply that if it was unknown to Europeans it needed to be “discovered” so it’s probably better to say Leifr was the first European to discover America, but of course it’s complicated. As far as we know, the indigenous peoples migrated here across the land bridges that existed at the end of the last ice age. There were certainly explorers among them – but we do not know their names or motivations. Indeed, there have always been “explorers” among us, going back to our early, pre-human ancestors, those who looked to the horizon and wondered what was there, and left the familiarity of their homes to find something better, or different, or just because. But as far as we know the major migrations were of the “let’s follow that herd of food” variety rather than the deliberate “let’s collect supplies, organize transportation, head out into the unknown and go find a new thing.” Again, no disrespect, but it’s not the same thing. (And, of course, this discussion is limited to the discovery of North America by Europeans – there were amazing explorers in the Pacific, the Middle East, India, and Africa throughout history).

The celebration of my ancestors like Leif is absolutely not to disparage Columbus – of course his explorations resulted in a permanent exchange between the hemispheres and radically changed the course of history. The Norsemen got here first, but their settlements were not permanent, in large part due to the rapidly worsening climate – but that’s a different post.

Continue reading

Invest off of North Carolina (Sat 9 Oct 2021)

There is a low pressure system embedded within a complex mess of weather is trying to form just off the coast of the Carolinas. The US National Hurricane Center has it at a 40% chance of tropical formation, and has started using the “Magic Words” and saying that “Interests along the North Carolina coast should monitor this system.” Here is the TAFB analysis with the GOES East IR view this morning …

click to embiggen.

The system of interest is the “L” in the center, next to the box labeled “DVLPG GALE” (Developing Gale). It’s not likely to become a significant storm in the hurricane sense, but if you are right on the North Carolina coast (the Outer Banks) it may be breezy. The “storm” is expected to move slowly northwest; if nothing develops by Sunday it’s not going to happen.

Invest area off the US East Coast, Earthquakes in #Japan and #Pakistan

There was an earthquake near Tokyo this morning US East coast time (evening Japan time), reports are coming in but some scattered damage (link goes to Japan Times). Given the quality of construction there, not expecting major damage …

click any image to embiggen.

Yesterday it was Pakistan’s turn, this one did cause at least 20 fatalities (link to Al Jazeera)

In the tropics, there is a weak tropical storm headed to Hainan Island, China, but shouldn’t cause a lot of damage. There is an invest area just off the east coast of the US, part of a very messy pattern across the southeast. Here is this morning’s analysis from TAFB (part of the National Hurricane Center):

The invest is the “L” off the South Carolina coast. NHC has it tagged with a 20% chance of becoming worthy of advisories. It is now being simulated by some of the models as AL92, but more than likely won’t cause anything but rain along the coast as it parallels the shoreline while moving northeast.

Earthquakes in the SC Low Country and Savannah

Just before 10 pm on the evening of August 31, 1886, residents of the Low Country thought the world was ending. The earth shook violently for over a minute, and in many areas the ground seemed to turn into quicksand, collapsing sturdy brick buildings in an instant. The earth continued to rumble, and a second major shock hit around 4am. Those few who slept did so outside. As the sun rose, the devastation became apparent …

Charleston, SC, after 31 August 1885 earthquake

In Savannah, terrified people ran out into the streets, and one woman leapt from her second story bedroom with her baby in her arms (they survived). But others were not so lucky, and while accurate death tolls were not kept, it was likely near or over 100. Although it took days for the full extent of the event to be known, it was felt over 2.5 million square miles, from Cuba to New York, with structural damage as far away as Kentucky. Every major building in Charleston is said to have been damaged or destroyed. With the recent spread of the newfangled technology of photography, we have a record in images of the aftermath (link goes to collection at the University of South Carolina). In Savannah, a twenty foot long fissure opened on Bay Street, and the facades on several buildings on Broughton Street collapsed.

The violence of the 1886 event came as a surprise to residents of the area – major earthquakes are not frequent. Historical studies reveal three major ruptures: the 1886 quake, one in the 1600’s, and one in the late 1300’s or early 1400’s. There is also evidence of additional earthquakes over the last 6000 years in the sediments of the region. Today we know a lot more about the subsurface geology of the Charleston-Savannah area. The University of South Carolina has a network of seismographs monitoring the region in real time …

Seismograph record for September 27th, 2021,

Just inland of the City of Charleston lies what we know today as the Middleton Place – Summerville Seismic Zone (MPSSZ). It is a complex structure consisting of at least two active faults. Unlike faults in the western US, these faults are buried under hundreds of feet of sediments and there is little evidence to be seen at the surface. While most people never feel them (or think it’s just a passing truck or car wreck on Victory Drive), there are on average between 10 and 15 minor earthquakes a year. By careful analysis of these events, the subsurface geology can be mapped, as seen in this diagram …

From Dura-Gomez and Talwani, 2009 (link goes to research paper).

The earthquake on September 27th was a reminder that deep under the earth there are forces that build over time, and must be released. While not located on a plate boundary, the Charleston area is on a dangerous, deep fault system that will from time to time violently rupture. Simulations show that if the 1886 earthquake were to happen today, there would be at least 45,000 people injured and thousands needing hospitalization for major injuries. Over 200,000 would be homeless. Many roads would be impassable, a third of hospitals in the low country and Savannah would be out of commission. The Beaufort and Hilton Head areas would also be severely impacted, with liquefaction (the ground becoming unstable due to high water tables and shaking) causing major damage and loss of life. While the most severe devastation would be in the Charleston area, many of the major buildings in Savannah would be damaged, with hundreds injured and dozens likely to die, and there would be structure damage across the US East Coast.

Unlike a hurricane, unfortunately while we know where earthquakes happen, we don’t know when the next one will occur. We can only estimate the probabilities. Here is the latest analysis from the USGS National Seismic Hazard Model …

Latest USGS probability of damaging earthquake in the US

So what are the odds? It looks like the chances of a major earthquake on these MMPZ system are about one in 400. By comparison, the chances of your home being severely damaged by a tornado is about 1 in 300, by other thunderstorm related winds about 1 in 180. A tsunami? Hard to say, the worst odds I’ve seen based on a solid scientific study are around one in 47,000, but I think they are much lower, probably over one in 250 thousand. The chances of a home in the Low Country and Savannah area being damaged by a hurricane is about one in 30, destroyed about one in 110. So while this is a risk to be aware of, and the consequences of a major earthquake extreme, there are other things to worry about. It is worth looking at the DHS/FEMA web site for earthquake preparedness (link), and remember that most of the things you do to prepare for a hurricane or other event are similar to that for other disasters.

Atlantic update, #Shaheen aftermath in #Oman,

There are two live storms in the Atlantic, both fading out. The National Hurricane Center also has a disturbance they are watching, but only with a 20% chance of gaining tropical characteristics. Here’s this morning’s analysis from TAFB:

Click to embiggen.

The disturbance is associated with the tropical wave (noted in red above). Conditions aren’t especially favorable for tropical storm formation, although GFS shows a nor’easter like low pressure system spinning up and impacted the northeast in eight or ten days. Nothing to get excited about yet.

Cyclone Shaheen is dissipating inland over the Arabian Peninsula, having caused a significant amount of death and destruction across Oman (link to Times of Oman reporting). There were also impacts in Iran as it side-swiped their southern coast. Landfall in Oman was weaker and further south than it looked Saturday, and impacts to the oil and gas infrastructure do not seem to be significant at this point other than delays in tanker traffic. Still, economic impacts of $500 million to $1 Billion are possible, and a number of deaths (twelve as of 6am this morning) have been reported.