[API] Lightning Map from local network strike data

I look at the map and all the stations around me. I find myself wondering if it would be possible to calculate a lightming strike map from the time of strike and distance to station. It really depends on how accurate the station locations and the clock sync’s are… But it would be cool to use the combined network to generate a map overlay with the strike location as calculated from the overlapping distance rings from each station.

It would be easier if the stations had direction data to go with the distance but I don’t know the hardware sensor to know that… If we had direction then these overlaps and direction would give us a good indication of who’s stations are not pointed true north.

Cheers!
:.)

A problem with that is that the sensor itself is designed only to report the strikes closest to your station, so another station might see a different set of lightnings. Note that the sensor isn’t very strict in following that rule, so you see plenty of strikes that are not closest to you.
(also note that this isn’t a software thing, it is part of the sensor’s logic)

I guess for storms that have only occasional strikes, this might work. but you always need three tempest stations to see that strike in order to determine the location.
This sensor has no direction data output. Distance data also isn’t very accurate.

The most reliable option is to join http://en.blitzortung.org They sell kits for lightning sensor to add to their network. But they only send them to areas currently not well covered.

That’s entirely possible though accuracy can’t be confirmed at this time. If several stations in your area are Tempest and the lightning senor for each is reasonably calibrated, a map could be created with a small margin of error.

As a single strike occurs data from the closest X number of stations would be compared. In essence it would be like drawing a ring around each station representing the inner and outer distance. Where all the rings intercept you have the distance and direction from your station.

It would require a lot of CPU usage considering the number of strikes and stations to create a real-time map for every station. The data is collected by WeatherFlow, there just needs to be an API function to pull the data and do the calculations.

It could be done and maybe someday WeatherFlow will have the time and resources.

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It isn’t that easy. Look at this image from the data sheet of the chip:


It shows the effect of what is hard wired in the chip. The chip in your station only reports the strikes at the corners of the red line. But a different station will see the storm from another direction and will report different strikes. If that happens, you might be able to create a map, but it will not reflect the position of the strikes. The only thing that you might calculate is the position of the storm.
This graph above is what is shown in the specs of the chip. However in reality the unit might report a storm like this:
untitled-3 That doesn’t seem to match up. But even this would be hard to resolve and get a correct map of the strikes. Still you might create a map of the location of the storm. And even that has to be taken with a grain of salt as you might deduce a strikes location even outside the storm (because data is used from different strikes)

I don’t know how the blitzordnung device works, but I do know that it uses a GPS. That gives you the exact time with a precision of 40ns. When you look at the speed of light, that travels around 12 m in 40ns. So in theory, but I’m not saying it does, the device might look at the time a strike signal arrives and with great accuracy calculate its distance. Not only that, but a blitzordnung device at another location will get the same very accurate timing, so they can be correlated. Given the size of a single strike, it doesn’t even have the determine the distance that accurately, but the accurate times of the event makes the correlation possible.
The Tempest unit doesn’t have this accuracy. So no, you can’t make a map of strikes, but you could make a map that looks like a map of strikes, but in reality is just a dot on a map stating that “hey, some lightning occurred, and most likely the storm is somewhere above this dot”

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Understood. There has to be an uncertainty in every calculation… I’m not looking for 10 m or even 100 m accuracy. As he said a basic indication of direction and storm track would be sufficient.

As you mentioned the timing accuracy is critical. I do not know how accurate the network time sync is or how far the clock drifts between check in to the time server. Nor do I know the accuracy the time of strike data is pushed the server with.

And most people probably just have their Street address not a good GPS coordinates for their station.

It is entirely possible to calculate from bad data. I’ve done it to many times.
And the answers look good on the surface.

Dreams of perfect data…

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The chip in the Tempest does not give direction, only an estimation of lightning distance. Timing, direction and distance (X a minimum of 3 receivers errors) are very critical when trying to pinpoint something moving with the speed of light. The other part is that once a company starts supplying public safety information to the public, no matter the disclaimers you have, you better be right.

I’m part of the TOA Lightning network ( http://toasystems.com ) that uses a deadicated receiver, 1M antenna and GPS receiver. They use a fairly simple system compared to Blitzortung but I’m still guessing this system has a price of $500 or more if purchased not counting all of the backend computing power that is used.

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