Wow! some of the distances from detectors to strike location are thousands of km. Now I am curious how it works. my guess is some sort of low frequency radio detector(long antenna?) and a good(gps disciplined?) timer. As the station integrator gets the reports it solves for what point could of generated this collection of time stamps.
Update: found the info page. It took me longer than it should have, but in my defense it was under the heading "cover your area"
You don't need a particularly good antenna to receive lightning strikes. At night, I can hear a thunderstorm almost anywhere in the midwest US just by turning on an any old AM radio.
But yeah, timing is critical to get an actual location.
If anyone needs historic data, let me know. They don't give it out if you're not a contributor, but becoming a contributor costs over a hundred euros and has a multi-decade waitlist if you're not from an area without coverage (very good coverage in Europe, of course..) so I decided not to wait for that. The data is Creative Commons so I felt it should be okay to collect for research and fun purposes
Email in profile! That's afaik the common or best practice. I can recommend doing the same since HN has no other way to reach out to an individual otherwise -- I'd already have shot you an email if you had ;)
I expect it'll indeed be good for students, can be fun to parse various statistics out of: from simple day-of-week counts, or how many strikes land near a few given cities/places (coordinates+radius), to exceedingly complex/predictive. We had some fresh-from-university developers apply who were not able to handle it properly, so also from an employer's POV I can recommend using some large dataset as teaching material (too big for RAM after decompression, but easily fits onto your SSD/HDD and it's decompressible sequentially on the fly to work with it)
Collections thereof are, however, protected by related legislation
And is there no creativity in the way they decide where the strike was based on the hundreds of measurements made? Besides not wanting to fight that one out in court, I'm also simply not wanting to be an asshole so I pay attention to their chosen license and pay it forward
For my kids, I have a virtual light switch in HomeKit called "Shower Is Safe". It's pinned to the top of the Home app.
I use the Home Assistant integration to fetch this data and run some calculations on the past few minutes of lightning activity. Since the API returns lightning strike time and bearing from a given location, I can (in combination with wind direction) determine if the lightning is approaching or receding.
If it's approaching and less than 30 minutes away (or if any strike is within 20 miles in any direction), it turns off the light switch. It then waits until it's been receding for at least 15 minutes (and with no more detections within 20 miles) before switching "Shower is Safe" back on.
I can (and do) override it if I notice it's potentially hazardous to shower.
I don't want to frighten your family more, but shower NEVER is safe. Unlike lightning, slips and falls in the bathroom are quite common and sometimes result in death or lifelong injury.
Attach it to a 10cm long string with something wide at the other end, so in the event of accidentally swallowing it (and ignoring the "why/how"), you can just pull it out. Problem solved.
Yes, especially in older homes or homes with poor grounding. Lightning can discharge through water supply lines[0]. There are even cases of toilets exploding due to lightning strikes[1]. (Google for more)
Sure, it's exceedingly rare. But it's also exceedingly easy to avoid. I've taught my kids that some decisions are easier when defined as binary rules; judgment calls in cases like this just don't offer any tangible benefit other than "I showered an hour earlier than I would have otherwise."
On the other hand, I wonder if you might be teaching a bad lesson about neglect of probability [1] here. The shower itself is probably orders of magnitude more dangerous by itself.
I'm wondering because I am also unsure myself if I should be concerned about lightning when showering, or whether it's statistically speaking an absolute waste of time :)
If you live in the lone, old house on a barren hilltop that gets struck by lightning on a weekly basis, I wouldn't take my chances with showering during the storm either.
In a lightning strike, electricity doesn't exclusively follow the lightning rod. That's the problem.
The major part of the current will flow through the rod, but a small remainder can and will cross into the house - TV/radio/sat antennae and overhead electric/phone wires are the main culprits here, but belowground cables and water/gas/metal sewer pipes can also serve as a point of ingress.
Normally you're supposed to have proper grounding at each of these ingress points as well as surge protectors, but all it takes is for one of the grounding connections to be a tad bit loose or a SPD being expired due to prior overvoltage events, and suddenly the pipes or whatever can pose a significant enough voltage differential to the rest of the house to kill you.
And if that news isn't bad enough, most people (especially landlords) do not care too much about their electrical and other wiring in the home. Every few years you should re-tighten wire connector screws with a torque wrench to make sure the connections are still up to the spec of the manufacturer, and grounding rods need to be regularly measured as well, particularly after drought periods to make sure they haven't dried out in the time since the last check/construction.
I did a home inspection on my house and really appreciated the insights there - many hazards were identified and it makes doing a rational de-risking exercise possible.
The difference in expected utility from showering (either during a lightning storm or not) is minimally affected by the choice to postpone it. That's why I'm content to call it a binary rule.
The choice of showering/bathing at all has a different risk profile, yes, and also a different expected utility. Comparing the two is a false equivalence.
Statistically speaking: our kids (and their parents) simply enjoy watching storms, and we all choose to shower when the risk of lightning is zero. That choice maximizes utility, as our subjective enjoyment of the light show isn't diminished by postponing something as pedestrian as a shower for an hour.
But its still a massively better approach long term rather than making up some hacking project, quadruple that if one owns the place. I mean sure its nice to see such creativity, but in our lifetimes how often do we see some... lets say a bit different folks being obsessed in one topic, neglecting all other aspects or much simpler, yet less 'hacked on my own' solutions.
I mean it literally, one example out of endless sea - a peer making some VR game about collecting virtual balls by vacuuming over them in pacman style, across whole apartment, so kids do the work. Instead of learning children to accept the suck a bit since life will bring you millions more such situations, man up and just do it, without additional external motivation and hand holding. But he wanted to play around with tech primarily, not thinking much about potential consequences (kids outright refusing activities that aren't fun and strengthening this mindset). Of course that vacuuming is also pretty crappy at the end, instead of thinking 'there is corner / weird place that I should cover too', they just run quickly through all virtual balls, missing the core reason for vacuuming.
I had to look it up, because this seems like a pretty unrealistic fear to me. What I fond:
> less than 1 in 1 million chance of being struck by lightning directly or indirectly
> One-third of all lightning injuries occur indoors.
I'm pretty terrible at statistics, but I think we can assume that there's a less than 1 in 3 million chance to be injured by lightning indoors.
But lightning related injuries indoors could also be from a window exploding after lightning hits a tree outside, or a fire related injury from a lightning strike to the house.
So what's the chance of being hit by lightning in the shower? And then being seriously injured?
Snopes lists 4 examples of people being hit by lightning in the shower, spread over 20 years. All of them with minor injuries. The chance of major injuries is also much lower than with a direct lightning strike.
So finally, is the 'safe to shower' thing useful? I'd say that making this is probably time that could've been spent on more useful safety related things.
Also, if it's just 'is it safe to shower?', it ignores tons of other dangers inside the house during thunder storms. Touching any tap, corded appliance, concrete wall or floor or being near an outlet is just as dangerous as being in the shower and none of those things are particularly dangerous in the grand scheme of things!
Not to disagree with you general point, but applying general risks to specific situations is not proper use of statistics. Once a thunderstorm is on, the risk just multiplied from the baseline risk for the people in the area. And it grows again for people who take a shower.
This [1] is the best I could find with a quick search, admittedly far from ideal, but it has some numbers to start with and might help to locate better data.
I don't know about this approach. Seems a bit panicky / heavy-handed to turn this particular risk into a "judgment call" compared to all the other risky things kids do. Could just be an occasional conversation / reminder:
- "We can't take a bath / shower right now. There's a big lightning storm outside."
- "Why not?"
- "The lightning hits the ground and it can spread through the water. It's not safe."
- "OK"
Is it really worth teaching kids to check this signal every day, instead of having this conversation like twice a year?
If the kids had to check multiple things before showering, this light would simplify the decision making process, but by the sound of it, it's redundant.
If it's unsafe enough not to shower, you'll probably hear the thunder too. There's your signal not to shower.
Though maybe it's not like that and the kids enjoy it.
It storms a lot here. And kids are notorious for not hearing things that are obvious to the rest of us. :)
My kids aren't paranoid, they don't freak out about the storms. It's just a natural thing, and a reminder that there's a potential that nature's best light show is in store for them. A nice side effect is that they're not afraid of storms—they look forward to watching them.
Ok, blanket advice from US governmental agencies and a Mythbusters episode with electrical and water installations that seem... Very DIY and not up to code? I mean it is mythbusters... IDK.
I suspect power outage in the shower is more dangerous in my case than any other electrical issue... I guess it may be more of a US issue, especially since I am not finding any advice from EU agencies on the matter?...
Building are different in different countries, and other geopolitical divisions. The UK authorities, for example, say it's safe to shower during a storm as long as your plumbing has been properly integrated into a standards-compliant equipotential bonding, noting that said standards change over time. So, you'd have to know them and trust/verify the builder followed them.
Or, you know, just wait a while and enjoy the show.
But is there any risk to you being in the path of least resistance? All your pipes are connected (to the ground) so why would the electricity not take the readily available metal path?
The risk of death of showering during a lightning storm could be the same as the risk of death going for a 15 mile drive[0].
A typical lightning bolt is about 300 million Volts and about 30,000 Amps. Since even the best-grounded home certainly can't sink 30,000 amps of current into the neutral-bonded earth bar, it has to go somewhere. It finds multiple paths, and the current is shared between them. There's also the conversion to heat in all those insufficient conductors, etc.
Electricity doesn't only take the path of least resistance, it takes all paths available in inverse proportion to their resistance (impedance really.)
And since the water and sewage systems are plumbing systems and not electrical systems, its highly likely they'd be at different electrical potentials in a strike.
Lightning strikes can induce significant current flows within all conducting parts of a building. This is obviously worse with parts that are not (or not well) grounded.
Basically without a lightning protection system you could stand next to a power outlet and a spark could bridge over to you and flow into the ground (there are slomo videos of such things happening in specific tests that have been conducted).
I think the shower warning app is a bit overkill. If your place is that frequently hit by lightning strikes I'd install a proper lightning protection system with a narrow mesh width and surge protection devices in all sections of the house. Yeah and ground that shower.
The hardest part about retrofitting such a system is getting a decent/low impedance ground connection. Ideally you'd embedded a steel mesh into the fundament and connect it to the lightning protection system on all sides. This is kinda hard if a house is already there, so digging deep on the sides of the house and trying to get connections under it (if possible) is the next alternative.
In any case make sure that ground impedance is actually measured..
Lightning has reached down from 10,000ft to strike the ground, do not make the mistake that it cares about anything humanity has built. Even with a lightning rod/abatement system, its probabilities and 'preferred paths.'
Plus, we really don't know all that much about lightning. Things like "ball lightning" (https://en.m.wikipedia.org/wiki/Ball_lightning) seem insane/impossible, but theres too many reports from everywhere on earth that go back hundreds of years- enough of them from reliable sources that its just "unexplained."
My father was born in 1930 and shared a bed with two siblings around ages 5-8. The bedroom was a small room at the top of the house and was on the wall where the electrical supply attached to the house from the street.
During a bad storm one night, they heard a buzzing sound at the window by their bed and saw an intense light outside. The ball lightning then entered their room at the window (I have no idea how that would work) and followed the wall out to the hallway. The whole time, they could hear a sizzling noise and the light was blinding.
Where it had entered the room, there was a fire outside where the electrical supply connected the house that entered the room. They took off out the door and down the the stairs. The fire damaged their house but did not spread (they think the rain put it out).
I have also heard that there was a family that had ball lightning enter their house down the wood stove chimney and emerge into their kitchen, followed the wall around the room, and the fizzled out.
Both incidents were a very long time ago. Other than that, I don't know anyone who has seen this phenomenon personally (my father passed away a couple of years ago).
Nobody knows. It's why it's so interesting, and controversial.
"Two children and fire? Ball lightning... I've never heard matches called that before..."
But then somebody stops and thinks... How would they know about Ball lightning at that age, in that age.
Repeat that with thousands of accounts across cultures, continents, and at least 500 years. It's a real humdinger. Descriptions of Ball lightning are, afaik, more consistent than how people of different cultures handle psych problems.
I find it comforting to know there's so much more about the world to explore.
I live on the 8/10 floor of a building that gets yearly lightning rod inspections. All piping has been replaced with polypropylene (clean water) or PVC (dirty) and even when it was metal, the electrical and water systems were far apart from one another. Even if they were not far apart, all wiring is underground. The transformer is inside a nearby building and also has lightning rods/wires and all wiring to and from it is underground. There is literally no scenario apart from ball lightning coming through my bathroom window while I shower that I can think of
Yes, it's exceedingly rare. But it's one of those "avoiding this activity for an hour could prevent you from dying painfully" things, so we don't shower/bathe/wash dishes when there's lightning.
> it's one of those "avoiding this activity for an hour could prevent you from dying painfully" things
If you do this often enough, for extremely unlikely scenarios that don't sum up to a meaningful aggregate risk of dying, you might very well have a negative return on investment though. (Time spent worrying about an unlikely sudden death is time you don't spend enjoying life, or at least avoiding a slightly earlier but much more likely death.)
As mentioned before, we don't worry. There's no judgment. It's a simple binary. And we spend the time enjoying the storm that we otherwise would've missed.
As a Floridian not far from a lightning belt world capital, I also never shower (or wash) when lightning is expected. I remember seeing a photograph of a car with a giant orifice where the hood and window were. Extremely rare, faraday and all, but I've seen some strikes that dignify paranoia and know several people who've lost family to lightning.
I'm more primitive in my safety measures, but that's a pretty cool system you have.
Edit: I also unplug my valuable electronics too, if I'm able. And yes, I've seen all sorts of stuff toasted, from cows to computers.
A similar one changes my LED-filled floor lamp (running WLED) to a pattern that matches the current weather conditions. Falling rain, lightning, heat "rising". Sort of an ambient notification system.
Another warns my wife if her commute time home is expected to be longer than usual, so she can opt to get a bit more work done if it means a quicker drive with a similar arrival time.
My favorite is the laundry notification. Current sensing outlets let us know when the washer or dryer is in use, and door sensors track if the lid to the washer or dryer is open/closed. So if someone starts laundry, the HomePods play a chime and announcement that "the washing machine is done!" If the door isn't opened in 15 minutes, it chimes again. Another 15 minutes, and a notification is sent to me and my wife. :D
{% set distance = states('sensor.lightning_detector_lightning_distance')|int(999) %}
{% set bearing = states('sensor.lightning_detector_lightning_azimuth')|int %}
{% set wind_bearing = states('sensor.pirateweather_wind_bearing')|int %}
{% set bearing_normalized = bearing % 360 + 360 %}
{% set bearing_left = (wind_bearing-80) % 360 + 360 %}
{% set bearing_right = (wind_bearing+80) % 360 + 360 %}
{% set distance_max = 20 %}
{% set bearing_min = ([bearing_left,bearing_right]|sort)[0] %}
{% set bearing_max = ([bearing_left,bearing_right]|sort)[-1] %}
{% set approaching = bearing_min < bearing < bearing_max %}
{% set close = distance < distance_max %}
{{ close and approaching }}
It normalizes the bearings to avoid dealing with the 0-degree crossover, and is reevaluated automatically whenever the three tracked entities change their state.
The automation itself is set to "restart" mode, and fires whenever the template sensor is true. It then waits for the sensor to be false for 15 minutes, and for the nearest lightning distance to be > 20 miles for 15 minutes.
Why a 20 mile radius? It's a good enough proxy for the time it takes them to prep for (get clothes ready, etc) and then actually shower (and brush teeth, 30 minutes total), and most storms in my area tend to move through at ~40mph.
I use their service ( https://www.lightningmaps.org/ ) often, it is perfect for getting an impression about the scale and distance of an incoming storm.
It's a bit of a shame, that their detector system project seems to be frozen/dead.
They just released a new detector so I don't think it is necessarily true that the detector system project is dead. I'm not sure how you get one of those boxes though: https://www.blitzortung.org/en/whats_new.php
I've been on waitlist for years (just checked my email - since 2014) and can't get one. I wish the whole project was more open and I could build my own from provided gerbers/BOM.
What I find the most annoying is that they don't give historic data to anyone who doesn't have a detector. But you only get a detector if you're in an area not already covered (not europe and north america for example) and even if you're in the middle of nowhere in Africa, there's years of waitlisting and the hardware costs. I gave up and built a scraper after an evening of looking into how to get a detector, but that means I only get future data of course, not a ten year history to do research on...
Yup absolutely. I don't like these open-but-not-really projects, though I can sympathize a bit. Some ADS-B exchanges and GPS RTK networks are the same way.
I've toyed with the idea of building my own (no huge network needed just send ~5 units to people around where I live). The RF stuff is bit out of my league though and I can't imagine how to test it, having to wait for thunderstorms.
First of all, Blitzortung is as far as I can tell independent, volunteer-based and thus open for everyone to use, support and feed with data. It is also real-time (or at least max 10-15 seconds of latency).
There are however drawbacks:
- The hardware is relatively expensive (relatively because when you compare it to ham or professional RF tech, it is in fact dirt cheap :(), so there's a barrier for entry into the network if you would like to cover your area. Add to that having an appropriate place for the antennas.
- There seem to be issues that make the default visualisation of lightning strikes as points on the map dubiously accurate. The example I notice most often is that whenever a lightning discharges in a cloud as opposed to the ground, it often gets detected as several lightning strikes. This may be as simple as adding the equivalent of error bars to each detection, but I am not any kind of authority on the matter.
GOES is not quite as spatially accurate as surface mounted detectors and IIRC fails to recognize certain types of flashes that are of interest to humans. It’s more of a general intensity meter than anything like a warning system.
Their technical documentation is extremely well written. They discuss most of their limitations in there (and you can get a SQS feed of it to poke around yourself)
And this map uses the same data, but looks a bit nicer: https://www.lightningmaps.org If you zoom in a lot, you can also see an expanding circle, which visualizes the sound of thunder.
I don't have much to add except to say that this is really amazing. I had no idea we had so many interlinked lightning strike detectors across the world. What's really interesting is from time to time, the detectors in Europe seem to be detecting lightning in the US.
Interesting to note that "electricity arcing through air" is pretty much exactly how our first radio transmitters worked, including the device used to send the first transatlantic signal.
"Since the attenuation of VLF waves is smaller for west to east propagation and during the night, thunderstorm activity up to distances of about 10,000 km can be observed for signals arriving from the west during night time conditions. Otherwise, the transmission range is of the order of 5,000 km."
Just a little teeny tiny bit of morbid curiosity, Blitzortung can also serve as a civilian early detection system for nuclear detonations in the rare, unusual, pesky occurrences of nuclear armageddons ;), a nuclear bomb detonation would show up in the signal with a much higher magnitude than a lightning strike and therefore could be easily detected as well, right?
If so, then it would be useful if Blitzortung could classify unusually high magnitude events and send out a special kind of notification. you would see the notification before you hear anything in the news (that is if you're still alive to see the notification and check Blitzortung).
"Nuclear detonations are generally realized to be strong
sources of coherent electromagnetic radiation (the elec-
tromagnetic pulse) within the very low and low-frequency
(VLF and LF) radio bands (3-300 kHz) [US. Department of
Defense. 1962. pp. 502-506)."
...
" The network consists of more than 500 lightning receivers and some central processing servers. The sources of the signals we locate are in general lightning discharges. The abbreviation VLF (Very Low Frequency) refers to the frequency range of 3 to 30 kHz." - blitzortung website
So I guess it seems like it sounds be possible, yea!
Hah, good plot for an "AI gone rogue" story... task an AI to code a nuclear launch detector, making sure to be a clean coder. It decides to do an integration test.
The twist would be it'd be the 100th nuclear launch, everyone on the planet is already dead and it's just the AI "alive" in a bunker under some mountain.
I'd be careful about this, they explicitly do not want you to use their websocket as a public api (hence the obfuscation in their protocol), I wrote a JS library and opted not to play cat and mouse with them.
Data is served through a public MQTT server (dedicated to serve requests for this component) - thanks to geohash-based topics and some other optimizations it greatly reduces amount of data sent to clients comparing to direct websocket connection to Blitzortung servers (it is also required by Blitzortung data usage policy - third party apps must use their own servers to server data for their own clients).
> The network consists of more than 500 lightning receivers and some central processing servers.
> The receiving stations approximately record one millisecond of each signal with a sampling rate of more than 500 kHz. With the help of GPS receivers, the arrival times of the signals are registered with microsecond precision and sent over the Internet to our central processing servers.
> Every data sentence contains the precise time of arrival of the received lightning discharge impulse ("sferic") and the exact geographic position of the receiver.
This link covers some technical details on how data is collected:
I remember looking at this for the first time many years ago. I don't remember the exact steps that caused the circumstance to appear but I left the page open with the sound on. For quite some time after that I spent ages trying to figure out where the intermittent clicking sound was coming from. It drove me nuts. I felt very silly when I figured it out.
Would be cool to get a system and contribute. I find it crazy just how far some of the sensors are triggered.
I’ve had a Blitzortung Blue sitting in a box just waiting to be soldered up - maybe this post kicks me into finally believing in my soldering iron skills and doing it.
I'm impressed with the range of some detectors.
Some lightnings in Japan are being picked up by detectors in the US' east coast, or detector in New Zealand picking up a lighting in North Africa.
Start with https://map.blitzortung.org/ . Zoom in to your area. Pull down the hamburger menu at the top right. Select the "Detectors" check box and slide the slider to the right. I found someone operating a detector a few miles from my house.
I've been using this for years. It's very useful in the summer season for hiking. There's an Android app that lets you configure alert if there's a lightning strike nearby. IIRC you could also buy their detector hardware and join the network to help improve accuracy.
I tend to use https://www.lightningmaps.org because it is less visually noisy but I believe it is ultimately sourced from Blitzortung. I unplug my computer whenever there is lightning nearby.
I've found lightningmaps.org to be somewhat degraded over the last few years. The web app sometimes just sits there and shows nothing. And blitzortung, the parent data source, still has the US divided into six chunks with no better resolution on the map.
I use this to make sure no Lightning is in the area when playing Golf. Had a couple of times where you hear a rumble, and see the lightning strikes are many, many miles away in the app, going away from you. So you can keep a close eye on it.
Pseudorandom but you’d have an issue with the fact that certain tall objects get struck all the time and there are better radio noise sources that are probably better at generating entropy.
Maybe the timing rather than the locality might be a better input.
> SAN FRANCISCO, CALIFORNIA--The jury may still be out on whether lightning can strike the same place twice, but a new study gives the public another riddle to ponder: Can distant lightning bolts talk to each other? Evidence gathered from space shuttle recordings indicates that, rather than being randomly distributed, lightning flashes appear to be coordinated, even when they're far apart.
> Coordinated lightning behavior has been observed before, but only over short distances. Over the past 30 years, however, astronauts who watched thunderstorms from space reported believing that lightning strikes influence each other even when hundreds of kilometers apart, a phenomenon astronaut Edward Gibson called "sympathetic lightning bolts."
> Sympathetic lightning is the tendency of lightning to be loosely coordinated across long distances. Discharges can appear in clusters when viewed from space.[22][23][24]
> From observation of lightning activity in severe storms with VHF radar the echoes from lightning discharges following one another within a time interval typical for a multistroke cloud-to-ground flash and spaced in range by several km are designated "associated discharges". The hypothesis of association between lightning flashes is tested against an alternative hypothesis of independence between them by using methods of statistical analysis for series of events. The hypothesis of independence is rejected at a level of significance of 5%. The probability for lightning flashes in multicell storms to be associated increases when time intervals between flashes are very short (<100 ms for the investigated storm).
I'm not soiling myself with youtube searches atm, but Pecos Hank has a fabulous channel and video on the subject of lightning types. Here's a link to a brief description on his site:
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Update: found the info page. It took me longer than it should have, but in my defense it was under the heading "cover your area"
https://www.blitzortung.org/en/cover_your_area.php
And here is a paper on the method used to integrate the reports.
https://wwlln.net/publications/dowden.toga.article.pdf