False positive?

[ARrrr]

Today there was a strike 5km from my detector (East Melbourne) that was recorded by 6 stations with the furtherest detection being in Sydney. The problem is that it's sunny outside with only a few clouds and no storm activity in the region. Also, I looked at GPATS and they didn't record it.

Does anyone have any idea what it might be? Is this a false positive or an actual strike? The disturbance lasts for around 300 microseconds. I read in the Blitzortung internal forum about "aircraft induced lightning" but I checked flightradar24 and there was no aircraft nearby at the time.

Details of the strike...

Strike ID: 1911512
Datetime: 2014-05-14 02:49:23.402515159 UTC
Location: -37.787124 / 144.944456 https://www.google.com.au/maps/place/37 ... !1s0x0:0x0
Current: 6.98kA

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[Tornado Tim]

A false positive is quite unlikely with a TOGA Network, which Blitzortung is based off.
If 6 stations detected the signal, its ether 100% valid or a large electrical discharge that has occurred in the area (to which I think is much less likely).

[ARrrr]

Thanks. I didn't realise you could get strikes on days like this.

[tgsnoopy]

Interesting to see this morning the addition of a detector in Hawaii.

[Tornado Tim]

Interesting to see this morning the addition of a detector in Hawaii.

Egon has bridged the station across multiple regions. America and the Oceania. Its doubtful if it will pick up anything we have here, but then again you never know the positive Cg's could get there

[davidgamble]

Today there was a strike 5km from my detector (East Melbourne) that was recorded by 6 stations with the furtherest detection being in Sydney. The problem is that it's sunny outside with only a few clouds and no storm activity in the region. Also, I looked at GPATS and they didn't record it.

Does anyone have any idea what it might be? Is this a false positive or an actual strike? The disturbance lasts for around 300 microseconds. I read in the Blitzortung internal forum about "aircraft induced lightning" but I checked flightradar24 and there was no aircraft nearby at the time.

This could be a "bolt from the blue" (http://www.lightningsafety.noaa.gov/bolt_blue.htm), a positive cloud to ground high energy strike. These are not all that uncommon and are the cause of the majority of lightning ignited bush fires.
Currently Blitzortung cannot discriminate the polarity of CG strikes but hopefully with the new e field antenna this will become possible.

[Tornado Tim]

This could be a "bolt from the blue" (http://www.lightningsafety.noaa.gov/bolt_blue.htm), a positive cloud to ground high energy strike. These are not all that uncommon and are the cause of the majority of lightning ignited bush fires.
Currently Blitzortung cannot discriminate the polarity of CG strikes but hopefully with the new e field antenna this will become possible.

It could be, but that implies there was already a storm to begin with. Typically +CG's develop when a Thunderstorm is in its mature stage as there is more of a charge differentiation taking place in the upper parts of the Cumulonimbus.
The only caveat to this rule is if the convection were significantly elevated, in which case the lightning being produced would certainly be +CG.
Positive CG's can be differentiated between there negative counterparts on Blitzortung by using the KA scale that Blitzortung currently outputs, its not technically accurate but it does give you the strength of a strike.

[Willoughby]

I once saw CG lightning in Hamilton on a mild to warm September 2005 day (17 or 18C), and it came from a stable-looking stratocumulus deck. It was truly bizarre and shows you really can't discount any possibility.

[davidgamble]

Where do I find the Blitzortung KA info?

[Tornado Tim]

Where do I find the Blitzortung KA info?

NZAPStrike shows that data, however the Strength format that gets ingested is 0'd out. Will have to check with Egon whats causing that.