Jupiter and Saturn

Conjunctions (the close approach of two objects) happen fairly frequently on a cosmic scale – Jupiter and Saturn pass one another about every 20 years, but today Jupiter and Saturn are the closest they have been in the sky since the year 1226, almost 800 years ago! This is one of those events that sounds a lot more spectacular than it looks. What you will see is one bright and one less bright star-like object in the sky that are less than the width of the full moon apart. The real show was in slow motion over the last couple of weeks as the two moved closer to one another. Here’s the view on the 13th and 18th (same focal length lens, slightly different times and camera position as you can see from the Spanish moss hanging down …). You can grab the slider (<>) and move it from side to side to see how much difference a week made …

Jupiter and Saturn, 13th and 18th of December

Through a small telescope you can see that these are not stars but planets … here is a view using a 400mm lens …

Saturn (top) and Jupiter. You can just make out the rings of Saturn and the cloud bands of Juipter in a small telescope. Although not visible in this shot you would also see several moons of each planet.

The real magic in this event is that you are seeing something that won’t be seen again in several lifetimes. People today are less attuned to the sky, especially given the lights in most cities block out the stars. Besides the sun, the only object most people see is the moon – and that often only when it’s full. But our ancestors watched the sky carefully, and noticed that some of the “stars” moved, and thought them to be special, perhaps messengers of the Gods or even the Gods Themselves. Those who watched the sky and interpreted the motions of the sun, moon, and stars noticed that in the years leading up to the year 750 AUC (Ab Urbe Condita, after the founding of The City – Rome) that there were a series of conjunctions between Jupiter, Venus, the Moon, and Saturn in auspicious constellations that may well have indicated to them that a new King would be born in Israel. That is one theory as to what the Christmas Star might have been, but there are others. From a theological standpoint seeking a naturalistic explanation seems to miss the point a bit since it is one of those things that probably isn’t going to convince anyone one way or the other. Besides, the Nativity was almost certainly in the Spring anyway … In any event, if you are a Christian or not, this is a window to a past where the majority of humans lived outside and were much more connected to the sky and their environment. So take a few minutes right after sunset and try to imagine what it was like thousands of years ago with no city lights, watching these mysterious objects majestically dance through the heavens …

The Coming Storm

No, not that one. Or that one. I mean the literal one, this one, the first big winter storm of the season. Here is the situation as of this morning (map forecast for 8am ET Wednesday, the storm is the “L” off the Georgia Coast):

Winter storm forming over Southeastern US … GFS model of precipitation type and moisture transport.

Like hurricanes, winter storms have to have a mix of conditions come together to cause them to grow and evolve. The key to weather on the earth is the need to balance the warm, moist air from the tropics with the cold, dry air over the poles. This happens in a number of ways, but in the summer the most dramatic are of course hurricanes. In the winter, it’s nor’easters. A classic nor’easter starts out as a low pressure system just off the coast of the Southeast. It moves northeast along the coast, carrying with it the warm moist air of the Gulf of Mexico and Bahamas, pushing that air inland where it meets cold polar air. It is along that swath where the air masses collide that the potential problems for Humans comes in. The danger this morning lies Appalachians and western North Carolina where the precipitation may be in the form of freezing rain, as well as inland in Kentucky (on the map, the red/purple area). Here is what things should look like this evening around 7pm. Notice that the low is deeper (stronger), the blue moisture transport vectors are longer (stronger), and across the New York/Pennsylvania area snow will be falling. The zone of freezing rain will by then have shifted to western Virginia.

The situation tonight …

By tomorrow morning the Low should be more elongated and off the Massachusetts coast, still pumping moist, snow-laden are into the NorthEast. The storm should be off the Canadian Marine Provinces by Friday.

Thursday Night

In terms of impacts, again the big concern is the area where freezing rain and ice will be falling. For the Northeast, snow could be fairly deep in places – some forecasts are for up to 24″ – but it’s more likely to be disruptive rather than truly dangerous, and again conditions should clear out by this weekend. For the Deep South (GA/SC), this will be a rain event, even for North Georgia. As things continue to cool off with the approaching winter season, the risk for ice storms will move further south … but the impacts of this event will be in North Carolina and the NEUS. How should you prepare for winter storm season? Take a look at the FEMA/DHS Winter Storm page for tips …

Yet another rant about COVID data

It’s one thing for the media to have “death counters” and for talking heads to spend 15 minutes an hour talking about the COVID statistics. Sure, it’s overly dramatic, misleading, causing a lot of unnecessary FUD (Fear Uncertainty and Doubt). But … entertainers are going to entertain. However, an awful lot of people are making life and death decisions based on week to week (even day to day!) fluctuations in COVID19 statistics. Does that make sense? Let’s take a look …

For a start, lets take a look at US Death reports, comparing the estimated numbers with the “final” totals for the latest reporting period, the week of September 12th:

Oops. Looks like there is a problem. First, (looks at calendar), it’s the 28th. The data for the week of the 19th is so incomplete it isn’t even showing up yet, only 25% or so of jurisdictions nationally have submitted data. Let’s put this in bold: we don’t really have solid numbers ( say, no more than 2% missing) for SIX WEEKS. Not six days, much less six hours (or, for TV folks, six minutes!). Here is a CDC paper describing the lags in the reporting system.

Now, let’s look at the reported deaths vs. the expected deaths. For expected we are using the average deaths in the US over 2000-2015, adjusted for current population. It varies from week to week during the year, more people die in winter than summer (mostly due to Influenza and Pneumonia). Here is the plot since February 1st of this year …

Two things are obvious from this plot: first, there is drastic under reporting in the most six to eight recent weeks (but we knew that from the previous graph). The second is that something out there is killing lots of Americans. So those saying COVID-19 isn’t that big a deal, well, that’s not what the numbers are showing – that’s not really the point of this graph, which is to show that the rapid tail off in recent weeks is probably due to reporting issues. We won’t have a good idea of what the data is for this week until November. That’s insane for a so called developed country with computers and telephones and stuff, but there it is.

Essentially all of the numbers you are seeing reported on a daily basis are ESTIMATES – not actual data. Now, the CDC, NCHS, Johns Hopkins and others doing the estimates are trying to do their best, and everyone is trying to get COVID data expedited through the system, but that’s actually a problem because now COVID confirmed deaths are being treated differently than other cases. and due to inconsistent testing and reporting it’s clear that we are missing a lot of COVID related deaths. Why do I say that? Take a look at this:

In other words, either there is another respiratory virus out there killing folks (very unlikely), or we are under counting COVID-19 deaths by around 20% (5 or 6% of total deaths).

And remember anything since week 28 or 29 (Mid August) is incomplete … so don’t get duped by the apparent tailing off since week 29 or so in this graph.

I could grind through this on a state by state basis; some are doing better, others worse, but you get the picture: the data isn’t timely or accurate. This is why (much to the annoyance of some) I don’t get bogged down in what this or that article (or even specific credible study in isolation) is arguing, trying to use the COVID-19 statistics to prove masks don’t work, or do work for that matter, or if the mortality rates are going up or going down or reopening is or isn’t working. Because to be blunt, the data sucks and we just don’t really know other than generally or anecdotally. That’s not to say the data is worthless – certainly we can see trends, and professionals can extrapolate a good bit from incomplete data, but this obsession with the death statistics isn’t healthy. Cases? Forgetaboutit. That’s even worse due to testing, reporting, and societal issues.

All this noise is why you can find an “analysis” out there (some credible, some not) that supports just about any point of view you want to try to flog. But if you take a step back and aren’t trying to make some political point, the picture is relatively clear: the SARS-COV-2 virus that causes COVID-19 is killing a lot of people who wouldn’t have otherwise died, we aren’t counting everyone who is being killed by it, and it isn’t going away.


Data Sources:
Excess Deaths Associated with COVID-19 (CDC).
Provisional COVID-19 Death Counts by Week Ending Date and State (NCHS).

#Sally landfall forecast impacts

Hurricane Sally should make landfall late tomorrow, with the US National Hurricane Center warning of “historic flooding.” Here are their Key Messages regarding Hurricane Sally (Spanish wasn’t available at 5:30am). But you may well ask, how is that possible given it’s not a very strong storm – only a middle Category One hurricane. Let’s take a closer look …

Here is the current infrared satellite view (the sun has not yet cast its baleful eye upon the Gulf). There are cold, dense overcast in the center, and as we can see on radar an eyewall keeps trying to form, but just can’t quite pull off a full eyewall or clear eye.

IR Satellite, 5;30am ET Tuesday; all graphics can be embiggened by clicking
New Orleans Radar at 5:25am Tuesday

And here is the MRMS radar composite for the bigger picture of the structure of the storm:

MRMS at 5:50am Tuesday

Aircraft data backs this up as well. All this means that contrary to the brief scare last night, rapid intensification and a Cat 3 landfall are just about off the table. Even Cat 2 seems a stretch. Sally is a solid Cat 1, and will remain so until landfall.

Here is the TAOS/TC impact map based on the 5am NHC forecast track:

Sally impact forecast

So why the “historic flooding” warning? The problem is that the steering (upper level winds that push storms around) is very light and changing slowly. So Sally is just drifting northwest at the moment at about 3-4 mph. As you can see from the regional radar, a lot of rain bands are pushing their way onto the MS/AL/FL Panhandle. So that is going to continue all day today and well into tomorrow. The rain totals just inland are in the neighborhood of 20 inches according to the latest HPC 5 day forecast:

HPC Rain Forecast

Because the winds aren’t that high, the surges would normally be somewhat nominal, but there are two aggravating factors. Storm surge depends on intensity, direction, and duration. Intensity isn’t so bad, but direction and duration are certainly favorable for high surges in some places. Ordinary we would expect a Cat 1 to product storm surges in the 6-8 foot range, but Sally will likely product surges on eastward facing shorelines of up to 12 feet such as parts of Mobile Bay and in the Delta. Overall, water levels will be at 4 or 5 feet above normal across the entire region from Panama City to the tip of the Delta. That, combined with all that rain, means the water has no place to go, and rivers, streams, and streets will have to deal with potentially a couple of feel of water. That is the reason for the inland rain warnings, especially in Alabama and the Pensacola area. Impacts will likely extend far inland, potentially to Montgomery. And speaking of inland, the rain swath is shown extending across North Georgia, and it is possible that the Atlanta metroplex will get dumped on later in the week with up to 8″ of rain. Atlanteans know what that means: grow gills, and prepare for epic traffic jams and stupidity. At least things look ok for New Oleans; it’s outside the excess rain swath, and while winds are blowing into the city off the lake, they should be light enough to not cause a big enough surge. As long as the city defenses work as designed.

Economic impacts are probably going to be in the neighborhood of $5 Billion, but that could easily double depending on where the rain ends up falling. Or, if the rains stay mostly offshore, impacts may be only $1 Billion or so. Ran is just about the hardest variable to forecast in these things …

#Sally Update, #Paulette, at 11am Sunday

The scary scenarios some of the high resolution hurricane models like HWRF were throwing up overnight have backed off somewhat, and in the 11am advisory the National Hurricane Center is sticking with around 85 knots (about 100mph, or Category 2) intensity at landfall. Key Messages regarding Tropical Storm Sally (en Español: Mensajes Claves). Thats “good” in a relative sense, but there are still circumstances around this storm that while not panic inducing, certainly keep it in the “be careful and be prepared” realm. Anything that dumps a lot of rain and storm surge in the New Orleans area is a worry. It is important to realize that the worst of Katrina was well west of the city, on the Mississippi coast; NOLA just caught the fringes. In terms of wind, despite being 100 knots (126mph) at landfall, winds in New Orleans itself were probably only in the neighborhood of category 1 sustained (80-90mph). The problem was the levee system failed and caused catastrophic flooding. Despite a weaker storm we are potentially facing something similar here for two reasons: first, lots of rain, with a slower storm. Katrina produced 10-12 inches of rain around NOLA. Sally’s current forecast is getting close to that:

NCEP 5 Day Rainfall forecast through Friday, 18 September

Notice New Orleans is right on the 8-10 inch range; it wouldn’t take much to kick it into the over 12″ range. A bit of a catch-22 is that when the storm surge protection masures are in place, it’s harder to pump rainwater out. Which raises the other big issue, storm surge from Lake Ponchartrain. New Orleans is essentially a big bathtub with a stopped up drain. The storm surge is extremely sensitive to the duration, direction, and speed of winds. This is a nice diagram from Wikipedia showing a cross section from the lake across the city:

Cross section of New Orleans (from Wikipedia)

Some of the storm surge scenarios for Sally put a lot of stress on the system due to the storm slowing down. If anything breaks it could get ugly fast. Again, this isn’t inevitable, but everything needs to work well to avoid a very bad situation. Currently on the Mississippi River side things look ok – the forecast is for a peak of around 10 feet, flood stage is 17 feet, so that side is probably safe (note the gauge stages are different from the elevations in the diagram). The lake side is forecast to reach at most 12 feet on the current forecast track and intensity – but 15 to 18 feet is not out of the question if Sally stalls out and the winds blow over the lake for a bit stronger, or a bit longer, than forecast. The good news again is that the duration of the “stall” seems tot be less and more importantly southwest of NOLA rather than south or over water, meaning the winds won’t be blowing water directly against the levee for so long. In any event, hopefully the storm will keep moving. That will reduce both rain and surge levels.

This isn’t intended to be scare mongering or alarmist, but to point out that New Orleans is a very vulnerable place. Right now the odds are definitely in their favor and a rapid intensification scenario is less likely. That said, it only takes a relatively small change in the scenario to narrow those odds (insert gamemaster comment here), and as I often point out, NOLA is one of those place where if something breaks that shouldn’t, the consequences are severe … so preparations are absolutely essential.

Out in the Atlantic, Paulette is still on track to hit Bermuda fairly hard tomorrow. Key Messages regarding Hurricane Paulette. They should be “hunkered down” at this point, tomorrow could be rough. Swells are reaching the US and Caribbean; if you go to the beach, beware of rip currents (or safely enjoy the surf if you are experienced and enjoy that sort of thing!).

The #Invest Thing Off Of #NorthCarolina #AL94 (8 Sept 2020)

Aside from Tropical Storms Paulette and Rene (note that’s a dude’s name in this case), there is an Invest (potential disturbance) area just off the coast of North Carolina that is getting some attention. It was designated as an invest area overnight, and is being tracked as AL942020, with a 40% chance of becoming a disturbance over the next five days by NHC. No watches or warnings. Check back in this evening or in the morning. That’s the official forecast. Let’s take a closer look at it since it is close to shore, and there is some probably misplaced angst over it.

Here is the infamous objective track model forecast map, aka “spagetti map”:

Available track models as of this morning; click any graphic to embiggen …

As a reminder, these maps are essentially useless and misleading. You have to cook the spaghetti and season it with experience (ack, that was bad). To start with, let’s get rid of all of the ensemble runs and just look at the prime track models:

prime model tracks, AL942020

OK, that’s not so bad – and in fact, for a weak disturbance without much definition, at first glance this is awfully good. If we look at the GFS model run and ensemble members (remember that the ensemble members are simplified runs of the prime model designed to assess the uncertainty in the main run), we get this:

GFS Ensemble Members from 00Z run

So … this thing will be moving towards the Southeastern US coast over the next five days. Of course, the track is just half of the story: how strong will it be when it gets wherever it is going? The ensemble members, as well as the prime runs that are truncated, are a bit of a clue: many of them die out before reaching the coast. But let’s look at this in a bit more detail. Here is what the last two intensity forecast cycles looked like for some representative techniques:

Intensity Guidance, 00Z Model Runs
Intensity Guidance 06z Model Runs

So you might think the trend is for stronger intensity, but beware: the ones trending higher are statistical models; the physics based (dynamical) models are for the most part not yet trending higher, and be especially aware that even the higher trending techniques are as of yet still only showing a minimal tropical storm. Looking at a solid dynamical track and intensity model, HWRF, here is what the overall picture looks like. Note that this does become a depression – then dies before landfall …

ohh, that’s not very doomy …

It is vital to remember that just because something might become a tropical disturbance or even tropical storm doesn’t mean it is an existential threat. Risks have to be kept in perspective. I try to categorize things as an inconvenience (windy, wet, rainy day with maybe some scattered power outages), hazardous (you shouldn’t go out in it, but if you are sensible will be ok), dangerous (lots of trees down, flooding), or life-threatening (winds high enough to seriously damage normal buildings, flood waters over a foot or two). This thing is likely to fall in to the “inconvenience” category for the vast majority of people in the “target” ‘area of the upper South Carolina/North Carolina/Virginia coasts, with perhaps some hazardous areas right on the coast or, as is always the case with tropical systems that produce lots of rain, hazards in low lying areas that can flood. Keep an eye on it? Sure – check back this evening or in the morning and see if it is developing. Wear out your refresh key? Not unless you just need the exercise … it is forecast to be slow moving, and so assuming you have a plan, nothing to get excited about yet.

A closer look at AL98 (and AL97)

The increasingly well organized tropical wave in the middle of the Atlantic Ocean is starting to cause some FUD (Fear, Uncertainty, and Doubt). The Orlando Sentinel irresponsibly says “with a projected path straight up Florida”). Lots of maps to embiggen and words to explain them today, for a closer look at forecasting a storm before it’s a storm. First, the official word: the US National Hurricane Center gives it a 90% chance of becoming a depression in the next 48 hours. Here is what their map looks like:

ZOMG! But what does it mean? Left to right, AL97, AL98, and doesn’t have a code yet.

On the left, AL97 – the current models take it across Yucatan as a weakly organized system, but then turn it north to varying degrees. GFS just a little, landing on the Mexican coast as a weak tropical storm. The dedicated HWRF model brings it into the Louisiana Coast as a weak hurricane. At this point Yucatan/Belize and Central America should prepare for heavy rains if, as expected, the system slows down before it turns (mudslides are always a bit risk there), but probably not hurricane conditions. It probably won’t spin up until it reaches the Gulf, although NHC will likely start tracking it before that. Too early for everybody else to worry about it.

AL982020 is the one to watch, and has a fair chance of becoming “Laura.” So, does the forecast say it’s “going up Florida?” Lets ask an expert:

The How About No bear says How About No.

It might do that. But there is no official forecast at this point. And that’s not exactly what the models are showing at 6am Wednesday morning, as there isn’t a lot of run-to-run consistency that far out. Here’s the spaghetti map:

I suspect the Sentinel got the “right up Florida” thing from the GFS Ensemble average (the orange/brown line labeled AEMN). And while a few other models show something like that trend, that just one solution. Remember that the majority of the lines in a plot like this don’t mean much independently, so let’s peel apart the layers. Here’s the primary dynamic models:

You could just as easily run a headline “straight across the Keys into the Gulf!” But that’s not as exciting I guess.

So what does “Primary” or “Ensemble”, mean? The earth and its atmosphere are big, and we don’t have weather stations all over it (especially over the oceans). Every 6 hours, we collect all of the weather station, ship reports, satellite observations, aircraft reports, millions of points of data, and create a “snapshot” (called initial conditions) of what we think the ocean and atmosphere looks like. Then we run models with the best resolution, model physics options, and so forth. That is the primary run. But, we know our “snapshot” isn’t perfect – there is uncertainty, so we create alternative initial conditions. But, doing another full primary run is expensive in time and computers, and if we ran them the same way we do the primary run, we could just look out the window because it would take more than week to finish the week long forecast! So we run a whole series of simpler but still good simulations. Those are called “ensemble runs.” We then look at the average of those to see how that compares with our primary run. Here is what that process looks like for two models: the main US GFS model, and the Canadian Meteorological Center’s model (click for the details)

GFS Ensemble
CMC Ensemble

There are others, such as the European model (unfortunately due to licensing I can’t show you that one), the US Navy’s model (which I could but I think by this point you get the message!), and so forth.

Also keep in mind these are just track lines – you have to look deeper to see that many of them keep the storm quite weak and even degenerate it into an open wave long before it reaches Florida. So even if it follows the Ensemble track, it may well just be a somewhat better organized cluster of thunderstorms, not much different from every other afternoon in summertime Florida. But enough of the models (like HWRF, which tracks across the Keys) show AL98 becoming Hurricane Laura that it is worth taking seriously.

It seems like I say “too early to worry about it” a lot. There is a good reason. We really don’t have good skill at forecasting these things more than five days out. The longer range models are getting better, but are not at the stage they are “actionable.” If you have prepared at the beginning of the season like you should have, one or three waves in the Atlantic isn’t your problem. If you worry about it beyond that, every time a tropical wave comes off of Africa during the summer you will freak out – which is every 2-3 days. This year there’s plenty to worry about. So at this point, in the US briefly checking the NHC site once a day to see if they’ve started advisories (Northern Caribbean maybe morning and night because it’s closer), replenish any disaster snacks you raided during the pandemic, and that’s about all you need to do.

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Finding the storm (#AL92, Wed. 28 July 2020)

First a quick review – Douglas skimmed just north of the Hawai’ian islands, causing much less damage than anticipated as only the weak side of the storm swiped them.  In Texas, as anticipated Hanna caused power outages, scattered damage, and some flooding.  As for the “investigation area” in the Atlantic, 92L, it continues to move across the Atlantic as an elongated tropical wave.  Here is what it looks like this morning, with the Tropical Analysis and Forecast Branch surface analysis as an overlay.  As usual, click to expand and see the details …

NHC still gives the system a 90% chance of becoming a storm in the next 5 days, with a completely unpronounceable name (Isaias) unless you are a fluent Spanish speaker.  So of course the usual suspects are sifting the entrails and trying to see where the computer model tracks are going.  Here is the track model map as of 6am this morning:

When looking at these maps it is vital to realize that they are lumping together models that probably shouldn’t be put together (like purely statistical models, as well as individual ensemble members).  You will hear terms like “ensemble runs” and “ensemble members”.  Just what does that mean?  Here are two examples.  The problem with a storm is that even in a stronger storm the exact position, and the surrounding environment, isn’t perfectly known (much less an invest area – look at the satellite map above and pin the fix on the storm!).  What an ensemble run does is start the storm in slightly different positions and intensities (perturbed initial positions is the technical term), and re-runs the model to see what happens.  Here is one example, the US Global Forecast System (GFS) run:

Notice the initial position for each track line is different.  The blue line is the “main” GFS forecast run, while the brown line is the average of the ensembles.  Notice how much variation there is?  (Actually, this isn’t bad for a weak system!).  Now, let’s look at another example, the Canadian model:

Again, for AL92, these are really rather consistent, which indicates a more stable environment (or, which is possible, they are all wrong in the same way!). The European model looks similar (but because of licensing restrictions I can’t show you that map) as do the Navy’s model and others.  The key point is to again reinforce the fact you can’t just pluck one model track – even a good model – out and get terribly excited about it (much less bet your life on it one way or the other).  This data has to be properly interpreted, and by far your best bet with respect to publicly available data is the official NHC forecast.

Administrative note:  As previously noted, I don’t have funding to do these posts and commentaries.  The last couple of months I’ve been trying to figure out how to do them that covers the costs – and even expand the features.  I don’t want to run advertising, so on August 1st I’m going to start a Patreon page where those of you who read all the way to the end can contribute to keeping these things running and help support the research work we do here, and get extra information including site specific forecasts from our commercial system.  I think we can do some pretty cool stuff, especially trying to get “plain English” no-hype forecasts for hurricanes and eventually other severe weather.  I hope you’ll think about contributing.

 

Whats in a name: Gonzalo, Douglas, and TD8 (23 July 2020)

After a long boring spell, the tropics got “interesting” all of the sudden.  Two storms in the Atlantic, and one headed to Hawai’i, so will be lot to cover today! But first we’ll start with a brief overview of how storms are tracked and named.

Last night the US National Hurricane Center started public advisories on the suspicious (investigation) area in the Gulf of Mexico.  As a reminder, tropical systems (Hurricanes, Typhoons, Cyclones, etc) are given unique formal identifiers when the reach a certain level of organization and intensity.   The first two letters are the Basin (area of world’s ocean – AL for Atlantic, EP for east pacific, CP for central pacific/Hawaii, WP west pacific, IO Indian Ocean, SH southern hemisphere).  The next two digits are the storm number for that year, followed by the year.  Storms are also given informal names to help in public awareness and watch/warnings. The number codes (called ATCF identifiers) are important since names are reused unless a storm causes a lot of damage and the name retired.  In the Pacific it is also important since some weather agencies (The Philippines for example) use their own names that are different from the other regionally accepted names.  Investigation areas are given temporary storm ids  in the 90 to 99 range, which are reused during the year since most of these don’t spin up.  So the system in the Gulf that had been given the temporary ID of AL912020 now has the formal tracking ID of AL082020.  In advisories it is being called “Tropical Depression Number Eight or TD8.  If it reaches tropical storm force intensity, it will be given the informal name Hanna.  But you will always be able to find it as AL082020.

So what is TD8 up to?  I again want to push the NHC’s “Key Messages” summaries.  They are a great, minimal hype, one-stop official summary of what you need to know about a storm, at least in the National Weather Service area of responsibility (Atlantic and East/Central Pacific regions). They are also available in Spanish, for those serving  Spanish speaking communities.  TD8 still isn’t that organized, but conditions aren’t unfavorable, so NHC is still thinking it will become a minimal tropical storm  before landfall.  Economic impact/damage should be minimal as well, under $10 Million if this forecast holds.  The key question is if significant evacuations become necessary.  Only those at risk from flooding, or in weaker structures like mobile homes should be seeking shelter – we really don’t need lots of people congregating in Texas right now with the COVID19 causing virus in uncontrolled community spread … here’s the impact swath:

The second storm out in the Atlantic is Tropical Storm Gonzalo (AL072020).  Gonzalo has expanded and intensified, and is expected to pass south of Barbados and across the Windward Islands in about two and a half days.  It is forecast to become a hurricane by late this afternoon, and maintain that strength as is crosses the Islands.  After that is a bit uncertain – there is a mass of unfavorable dry air in the central Caribbean that should knock Gonzalo down pretty quickly before it reaches Jamaica.  Impacts are estimated at under $5 Million on this track.

Finally we have Major Hurricane Douglas.  Douglas is an impressive Category 3 hurricane, but fortunately no where near land at the moment.  It is forecast to hold this strength today, but should begin to decay as it approaches the islands of Hawai’i in about 3-4 days and should be just below hurricane strength as it passes over the islands.  Here is the TAOS/TC “plain English” impact map:

The main risks from Douglas at this point seem to be heavy rainfall, but winds could still be over hurricane force along higher elevations and ridgelines.  We’ll know more in a day or so once it starts to decay.

Georgia COVID deaths: the critical week ahead

Before we revisit the mortality projections, let’s take a look at the big picture. As I have said many times, each disaster has its progression in time.  Earthquakes are measured in seconds, hurricanes in hours to days, pandemics in weeks (and foreign policy or environmental disasters often in years to decades from their roots).  For example, while it might seem longer, the sharp rise in positive test ratios (again, not an increase in the number of tests, but the percentage of those tests coming back positive) in states like Florida, Arizona, Louisiana, South Carolina, and to a lesser extent Georgia, began about 20 days ago.  If the pandemic follows the experiences in the Northeast and Europe, the upcoming 10 days will see a significant increase in mortality across these states.

Georgia is an interesting case.  If the data can be trusted (and I’m somewhat skeptical), Georgia was in a “slow burn” both during the “shutdown” (which was a bit porous), then opened earlier than other states.  Georgia’s mortality “curve” was not as flat as other states, but the increase in positives and hospitalizations has not been as sharp either.  Here is what the curves for positives looks like (again, we don’t have a good “case” count because of all the asymptomatic cases and lack of comprehensive, random testing):

And here are the mortality curves (remembering these tend to lag 20 to 30 days behind the positive curves):

If you blend in all of the various data (positivity rates,hospitalization rates, mortality rates, complications among those who have recovered, and so forth), what we are seeing is a mixed picture.

So let’s revisit the graph from about a week ago, with the forecast for deaths in Georgia.  I’ve added two other lines.  The first is an optimistic projection, in yellow.  While I never saw advocates of that position put their forecasts in to hard numbers, I used their stated assumptions (that the vast majority of new positives were among young people, and their mortality rates were uniformly lower based on the early mortality data among those groups).  The second new line, in green, is the pessimistic assumption, that the observed rates will persist as the virus expands into a younger population with only marginal improvements.  The orange line is the “balanced” projection based on the May 30th data and trends, the blue line are the reported deaths.

To state the obvious, the pessimistic line is way off.  Clearly improvements in treatment, as well as the increasingly younger patients showing up in the hospitals, has meant the mortality rate has come down.  Yet, not as much as the optimists (the yellow line) were arguing/hoping.  The “balanced” projection is doing better, but is still high, although the divergent trend in the last couple days might be due to the weekend.  The upcoming week is critical both from a policy standpoint as well as seeing into the future, as we see how the increase in positive tests 20 days ago (and increasing hospitalizations) translate into mortality.  Will it stay in that middle ground, increase, or decrease?  We should know in about 10 days (weekends screw up the data in Georgia and many other states due to reporting issues).

So what does that all mean?  From a personal action standpoint, not much.  Get a mask and wear it properly in the appropriate situations – inside with people outside your family, outside where close contact (less than six feet or so) is unavoidable. Keep in mind masks do you some good – but mostly prevent you from spreading if you have it – and remember you might be and not know it.  Use good hand hygiene.  If you think you might be sick stay home.   The same stuff that has been said for weeks.

From a societal standpoint it’s complicated.  Because the COVID19 data is mixed, and it’s not either an “in your face” catastrophe or an equally obvious “nothingburger”, it makes it easy for partisans to argue either way and pretend their policy options are “right.”  Compromise is essential – but sadly that doesn’t seem to be in the short term political interests of either side trying to create advantage for the upcoming election.  In my opinion reimposing shelter in place orders is not practical and is causing more damage than good.  The reason is that unless you enforce it uniformly across the country, there will always be brewing pockets ready to spread as soon as you release the restrictions.  The only way to beat this thing is by personal responsibility and encouraging, even mandating it, but figuring out a way to do it that without damaging our increasingly fragile civil rights.  What about schools?  That’s a really hard one. I think it is important to restart in-person instruction – most independent studies show virtual instruction just isn’t as effective as in-person classes.  But I don’t see how you can do it unless students are required to wear masks and aggressive steps taken to protect staff.  Ideally classes would be kept together, which is practical with elementary school but increasingly problematic in the upper grades.  It’s a hard problem, and public health and educators need to be working in close cooperation to figure out creative solutions.

In short, everyone needs to be reasonable and try to solve this rather than score points. You’re not being a sheeple to wear a mask and being careful; likewise, it’s not heartless to say we need to try to get our economic, educational, and social lives back to normal.  Balance.