The Gentle clop-clop of coconuts (Tropical Storm Arthur, Sunday 17 May)

Yesterday evening the National Hurricane Center stopped mucking about and took note that The Lady of the Lake, her arm clad in the purest shimmering samite, held aloft Excalibur from the bosom of the water, signifying by divine providence that the blob of clouds off the coast of Florida had become Arthur, first of the Tropical Cyclones in the Atlantic.  Here’s what it looks like as the sun rises gently over the parapets … infrared on the left, visual on the right:

It seems that Arthur is destined to wander offshore, searching for the holy grail of warm water and low shear.  As always in such cases, consult the NHC “Key Messages” summary, which you may find carved in not very mystic runes upon the very living internet, for clues.

Here is the TAOS/TC impact map … the worst of the effects will likely stay offshore.

There does not appear to be any hidden rabbits with big, sharp, nasty pointed teeth involved, but if you go the any of the beaches in the Southeastern US over the next couple of days beware, for there are tides that may rip you from the shore and sweep you out to sea … (rip tides will be bad the next few days).  There is a tropical storm warning for the Outer Banks of North Carolina – appropriate precautions should be taken for some wind, heavy rains, and perhaps  some coastal flooding.

Let this be a reminder that you should take some extra precautions in your hurricane planning this year.  Or I shall have to taunt you a second time.


Note for anyone who is totally confused about the above: it is all a part of growing up and being British.  Or a Monty Python fan, which is probably the same thing.

AL90, Invest area over the Florida Keys; where to find info

The Thing from The Gulf (2020 Remake) has moved over south Florida, and is expected to become a tropical depression in the Bahamas over the weekend.  So you know what that means … spaghetti maps!  Long time readers know that spaghetti must be cooked: if you don’t have years of training and experience (something that, no disrespect intended, even most working meteorologists don’t have, especially the local TV guys), interpreting tropical cyclone track forecast models is best left to the experts.  Don’t get caught up in the model guessing game, there is only one track that matters for your planning purposes: the official National Hurricane Center (NHC) forecast.  And, at this stage, there isn’t one, since official advisories have not started.  But NHC has a really great product that is started whenever something might have the potential to impact land: the key messages product. The “Key Messages” graphic should be your first step to see if you need to panic, and how frantic the panic should be. Don’t have a plan?  FEMA/DHS have a web site with lots of checklists and advice.  You paid for it, use it.  While this storm will probably not have any significant impacts, it should be a reminder that if you live on the coast, you need to have a plan.  Especially this year.  Look for a post in the next few days on how the COVID19 pandemic should change your hurricane evacuation plans.

Since AL90 is still an investigation area (INVEST), there is not official forecast track, only the five day outlook map.  That outlook is based on track models, global weather models, and forecaster experience.  The computer track forecasts look like this at the moment:

One thing to remember is that other than the colored lines, most of these tracks are actually variations on the same model designed to assess forecast uncertainty.  You can’t just pluck one line out and go “ZOMG!  That line hits my house!”  Let’s take one model, the US Global Forecast System (GFS):

The blue line (AVNO)  is the main model run.  The twenty thin gray lines are known as “ensemble members”.  These are model simulations that were started (“Initialized”) with slightly different, but reasonable, conditions.  For example, with a weak storm, we really don’t know exactly where the center is.  So the center is  started in different positions to see what happens.  The average of these ensemble members is the brown line (AEMN).  For this storm at this time, being so weak, this is a pretty tight grouping.

Normally we don’t do this with model forecasts, but since we don’t have an official track and want to see what this thing might do, we can run the GFS model track in our hurricane damage model to see what the winds and damage might be. Here is what that looks like …

So as we start another Atlantic Hurricane Season, please try to keep perspective.  We face many challenges between COVID19 and all of the fallout from that like the economy, and trying to think about One More Bad Thing is disheartening.  But, of all natural disasters, while hurricanes are destructive, you can see them coming.  We know, in comparatively accurate terms, who is at risk, and what they should to protect themselves.  Ignore the media hype and exaggeration, have a plan, be sensible, and you’ll be ok.

Tropical Doom, real and imagined

Out of the fetid, miasmic waters of the Gulf of Mexico something stirs … or not.  Besides, after the last couple of months it’s hard to get too worried about hurricanes.  At least you can see them coming, unlike a virus particle on the doorknob left by someone who was irresponsibly distributing political leaflets, hanging them (and probably touching) EVERY SINGLE DOORKNOB IN OUR NEIGHBORHOOD (in Savannah, GA).  Sending someone out to do that in these times should disqualify a politician (Michael J. Hamilton, Sr.) from running for office … but I digress.

Typhoon Vongfong took a turn for the worst yesterday, and has made landfall in the Philippines.  It is likely causing the equivalent of $1 Billion in damage, and the evacuations and sheltering are probably exacerbating the spread and control of COVID-19 in that country. The problem is that the things you need to do for a hurricane, move populations around in evacuations, put people together in shelters) are EXACTLY the opposite of what you need to do for a pandemic! Here’s the latest impact map …

There is a system presently over South Florida that the US National Hurricane Center is excited about.  They give it a 40% chance of spinning up in the next 48 hours, and a 70% chance within 5 days.  Very little tracking data on it available this morning, the normal track models haven’t spun up yet, but if you just need a line on a map here’s something … this track starts at 7pm tomorrow (Friday 15 May) and runs until Sunday night.  After that the storm continues north, off the coast of North Carolina.  Not likely to be much of a threat to anybody, but may get some news coverage.  The Bahamas are still suffering after Dorian, but I doubt this will be a significant event unless something radically changes before Saturday.

Hopefully decision makers and emergency managers are thinking about how to modify evacuation plans and sheltering protocols.  My strong advice is to revert to the old (and IMNSHO best) guidance: evacuate from water, shelter from wind.  So you only evacuate flood prone areas.  Most people will be ok in hurricane force winds in reasonably well built homes up to about Cat 3 (when buildings start to collapse).  Mobile Homes, of course, need to get out, but setting up local shelters (which many coastal counties are reluctant to do) are essential to avoid spreading the virus to outsiders (or bringing it back in when evacuees return).  So evacuation guidance must be more nuanced than the traditional “evacuate the entire coastal region” or evacuations and sheltering are going to create a massive vector for spreading the SARS-COV-2 virus, just in time for the fall respiratory disease season.

Having fun with raw data

Here’s a plot the number of new test results per day for a number of states, normalized by population.  Notice anything odd?

Um, negative new tests in South Carolina yesterday??? and, three weeks ago, in Louisiana?  And what happened in Puerto Rico???  Are they un-testing people? Tossing out previous results? Alien Abductions(tm)?  Just plain tabulating errors?  I’m not sure exactly what is going on with this data set (the testing reports are from SC DHEC) but it shows you the perils of crunching numbers without looking at them – that would blow up any results derived from the number of people tested.  This is also why I don’t post charts every day, or plot every state/country (much less keep rolling Death Counters in the upper right hand corner of the screen updated in real time).  I wait to try to figure out what is going on first, and what the quality of the data is.  And as noted in a previous blog, it’s pretty wretched for a so-called industrialized country …

So let’s let the pandemic data simmer until next week.  Besides, there is an invest area in the West Pacific that might become a storm and impact the Philippines next week …

 

Midweek Numbers and Analysis Update (6 May 2020)

As long time readers know, one of my main frustrations is with the “News Cycle” and how there is constant pressure to come up with “new” or “breaking” news. It’s not rational or conducive to mental health.  Most events move slowly.  For Hurricanes, things change on a daily to 12 hour time scale – certainly not hourly or less – until the storm is near landfall, and even then a three to six hour update is fine.  For a pandemic, things move far more slowly.  Even daily updates are problematic – it takes time for testing results to be available, and just the course of the disease is measured in weeks as it takes 5 to 10 days for someone who is exposed to become infected (and/or infectious), another 10 days or so of illness, if hospitalized that extends to 20 days.  Hospitalization and confirmed positive numbers are a look back in time about a week – deaths, about three weeks.  Throw in the noise and inept reporting in some states, and the moving target of what is a case vs a COVID death … well, you get the picture, and it’s pretty fuzzy.

But since it has been a few days, let’s see if anything has changed – certainly the mitigation measures have, as states like Georgia have begun to lift restrictions.  But, for the reasons noted above and in a previous post, we probably won’t see any serious impact on the numbers from these measures for about another week.  So looking now is a snapshot into what was happening when the measures were expiring.

First, lets look at testing.  Despite all the talk, only a very small fraction of the population has been “tested” (noting that being tested means different things – tests for active infection have very different meanings from tests for antibodies, and all of the tests have error rates and interpretation issues as this paper demonstrates.  So how many people have been tested?  Here are the results for five states …

… only NY is above 5% of the population.  If that were a random sample that would be great, but unfortunately it isn’t.  So what fraction of those tested are positive? Continue reading

Time to be blunt: the data sucks.

Good information is vital for decision making.  With respect to the ongoing pandemic, leaders and internet experts alike in the US are analyzing the numbers, doing projections, making plans, not to mention news outlets scaring the poop out of people with “death counters” and “breaking news” of new numbers.  There is just one problem: all of this is based on numbers that are so noisy they are almost useless. And there are powerful political forces in both “tribes” driving the data in to places it doesn’t want to go – something much easier to do with bad data.

Yes, often you have to work with data that is noisy. Experts do it all the time. But I can’t recall seeing so much analysis, decisions, and opinions rendered on vital subjects on data that is so crappy – often by people with little to no experience in dealing with noisy data.

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Frustration with data and politics; updated charts (15 April 2020)

In many parts of Europe, there seems to be a light at the end of the tunnel.  Denmark (added to the chart), which took early action, is reopening schools and day care for kids under 11, as it appears their response has things under control.  It is interesting to compare the Denmark, Norway, Sweden, and Denmark, as each took different approaches to societal restrictions.  I’m sure many papers will be written!  Spain seems to have hit the inflection point of their curve, but while cases are down, the death rate in Italy continues to climb.  This might be a data and recording problem – their system was so overwhelmed deaths are just now being recorded that happened days ago.

In the US, it’s hard to tell what is going on.  Testing and data tracking in this country is an embarrassment for a so called developed country.  Continue reading

What do you say when nothing has changed?

One of the problems with a 24 hour infotainment (aka news) cycle is that there is constant pressure to come up with “new content.”  If I don’t post something for a day or so I get messages from the usual social media suspects that “your thousands of followers haven’t heard from you in a while, write something!”  Honestly, given my research subjects, I think  most of my followers are perfectly happy NOT hearing from me.   But if you’re in the professional content business you have your kleptocaptialist corporate masters to serve, so you have to come up with something.  So you do.  Even if it’s more trivia than information or news – the more inflammatory the better.  So, if deaths are down in one area, play them up in another.  The political shenanigans are always great for hits, and politicians are always looking for a camera to love.  “Things are moving along as predicted, hang in there, nothing new to report” just doesn’t sell the latest prescription drugs (insert rant here).

So where do things stand?  There is water under the ocean (same as it ever was)The numbers and forecasts haven’t really changed a lot, so as frustrating, boring, and economically harmful as it is, keep on keeping on with the CDC guidelines

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Numbers and trends (6 April notes on COVID19, and a hurricane???)

Yes, a hurricane; it is still hurricane season in the southern hemisphere (technically a tropical cyclone, called a Typhoon in the area it is traversing).  SuperTyphoon Harold is moving through the islands northeast of Australia, and has killed 27 in the Solomon Islands. After a loop it is moving through Vanuatu and headed just south of Fiji over the next three days …

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Saturday 4 April Chart; New CDC guidelines

Here’s the updated mortality graph (click to embiggen!) and forecasts for those who are obsessing on the numbers.  Note I shifted the scale a bit as NY and Spain were too close to the top of the graph.  NY is on a bad trajectory, steeper (meaning more cases/deaths faster) than Spain due to later restrictions and bad manners, but hopefully to no greater of an end point mortality rate.  Speaking of Spain, it does seem more and more that they have “turned the corner.”  Italy is a mixed bag, the spreading in the south and reporting lags are pushing their “curve” higher, but it should trend downward over the next few days.

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