Realtime Lightning Map

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  See supporting info below the map. Do not use for human safety or protection of property purposes.
    No Active Thunderstorms 9/20/17   19:41:27
Strikes Close
0 0
Peak Rate: 0/min
Time: ---
Peak Burst: 0/sec
Time: ---
Last Strike
Time: ---
Distance: 0
Direction: 0.0°
Type: ---
Uptime: 102:39
Squelch: 0
Alarm: Inactive
Updated Last:
Strikes Distribution
  Today 30 min.     Today 30 min.  
pluscg cgtoday
0 0%
0 0%
  pluscc cctoday
0 0%
0 0%
minuscg cgtoday
0 0%
0 0%
  minuscc cctoday
0 0%
0 0%
Strike Totals
  Total Close
Today 0 0
30min 0 0
Strikes /min
last 24 hr strikes
Update Rate   Map:    Storms:    Graph:
NSDisplay Design by and Maintained by

Map Legend

The MHW lightning detector can identify the direction, approximate range, and type of lightning. Cloud to Ground is obviously much more dangerous than intracloud. Both show how much energy is in a storm cell.

Strike ID Key
Strike Symbols
  +CG = Positive cloud to ground strike
-CG = Negative cloud to ground strike
+IG = Positive intracloud strike
-IG = Negative intracloud strike

TRAC key  
Storm ID Key
Dashed DiamondStrike Rate/MinClassification
L-1684 is a computer assigned identifier.
- or + indicates dominating strike polarity.
1 indicates last recorded strike rate.
^ - v indicates if storm is increasing, steady, or decreasing.

About the MHW Lightning Detector

Boltek PCI Lightning Detector System's lightning detection center is powered by a Boltek StormTracker PCI. StormTracker works by detecting the radio signals produced by lightning. These are the same signals you can hear as static on an AM radio during a thunderstorm.

StormTracker's antenna is a small black box (3"x2"x1-1/2") that consists of a crossed loop magnetic field sensor and electric field sensor. The antenna is mounted in the attic of MHW's house. The antenna is connected to our dedicated weather PC where a special PCI card digitizes the signals for subsequent analysis by software.

The system records four types of lightning:

  • +CG Positive cloud to ground strike
  • -CG Negative cloud to ground strike
  • +IC Positive in cloud or intracloud strike
  • -IC Negative in cloud or intracloud strike
  • Noise - electrical signals from other sources than lightning
Our lightning data is submitted to

Technical Description of Lightning Detection

The NexStorm software from Astrogenic Systems determines stroke type at the software level. For each electro-magnetic pulse that occurs (i.e. for each lightning stroke) the software will obtain a signal waveform which is analyzed in real time.

There are numerous signatures in a waveform that can tell what type of stroke it was. To determine polarity (positive or negative) the software looks at the electric field at various points in the waveform. To determine the type (cloud to ground or cloud to cloud), the software looks at total waveform length, rise times to peak, peak to zero crossing times, etc.

Direction is determined by looking at the magnetic field ratios for each stroke and using basic trigonometry, i.e. crossed loop antenna direction finding principle.

Initial distance is determined by looking at the signal strength. This however is not very reliable because the signal strength of various strokes occuring at the same exact distance will vary a lot depending on released energy. Therefore, in single antenna lightning detection systems, Nexstorm averages each stroke against a cluster of other strokes that are located towards the same direction, and from that derive a distance to the entire storm cell.

Thunderstorm Ranging and Acquisition, or TRAC for short, is a sub-process in NexStorm that contains all the logic behind computing where thunderstorms are located and analyzing their characteristics. TRAC can also produce a text-based report based on its findings to show you details about individual storms. The TRAC related on map identification feature uses TRAC data to display important information about a thunderstorm. When TRAC has detected what it believes to be a structured thunderstorm system, it will start tracking it until the storm dissipates or the tracking could not be maintained for other reasons.