Bear Basin Lightning Fatality of 03 July 2008:
Lightning fatality of a 16 year old riding a mountain bike in the Wet Mountain in Custer County, Colorado

 

Stephen Hodanish
National Weather Service
Pueblo, Colorado

This research is part of the Lightning Casualty Case Study section of the Colorado Lightning Resource Page, NWS Pueblo, Colorado. 

"The primary reason for these lightning casualty case studies is to observe where victims were located relative to thunderstorm activity when they were struck".

      Introduction

On the afternoon of 3 July 2008, a 16 year old male, Landon Dillard, was killed by a lightning flash while riding a mountain bike on a dirt road in the Wet Mountains in Custer County, Colorado. The fatal flash occurred 0.60 miles to the north-northwest of CO highway 96 and Custer County road 271 (fig 1). The 16 year old male was riding towards the southeast on county road 271 with 5 others when the flash occurred. 

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 Fig 1. Topgraphical map showing the location of the lightning fatality, denoted by the letter “A” in the center of the image. Map image from Google.

 

     Description of the location where the fatality occurred

An examination of the location where the fatality occurred showed that the fatal flash occurred in a relative open area. (Fig 2a-b) To the immediate south and west was pastureland, while to the north and east was hilly scrubland with a few pine trees. Except for a couple of road signs (speed limit signs), no isolated tall objects were in the immediate vicinity of where the flash occurred.

Information gleaned from both eyewitnesses and from the Coroner’s report indicated Landon was 2nd in line of the 5 cyclists who were riding on this day. At the actual time of the flash, the riders were spaced about 2 miles apart, with 3 of the riders in the lead pack (including Landon), while the other two were much farther behind. The first cyclist in the lead pack was approximately 7 yards in front of Landon when the flash occurred. This first cyclist did feel the electrical shock from the flash and was knocked off of his bike, but received no injuries. The cyclist that was behind Landon was approximately 25 yards behind and was not affected by the flash.

     Data analysis

In order to observe which lightning flash caused the fatality, two pieces of information need to be known. The first piece of information is knowing the exact time when the lightning flash hit the victim, and the second is the location of where the victim was struck. Typically, the victims' location is well documented.  In this case, the victims’ location after the incident occurred was identified, and was documented by GPS at 38.17161N, 105.29401W.

The time of when the flash occurred is also believed to be quite accurate. Shortly after the flash occurred, the cyclist in front of Landon ran over to the Bear Basin Homestead which was located just a little more than a couple of hundred yards (216 yards) from where the fatality occurred and had the residents dial 911 (see figure 2). According to the Custer County Sheriff’s office, a report of a lightning strike victim arrived at the 911 dispatch center at 4:44 pm MDT (2244 UTC). 

 

 

Fig 2a

Fig 2a (above) and 2b (below). Photos showing the location of where the fatality occurred. Photo in Figure 2a (above) is looking towards the southeast. The black bag in the center of this image marks the location of where the flash struck the cyclist. The victim was pedaling away from the photographer in the image above. The red barn in the photo is the Bear Basin Farmstead. The speed limit signs can be seen in the image (see text).  Figure 2b (below) was taken from the intersection of CO highway 96 and Custer County farm road 271 (see Fig 1 for reference). The photographer was looking towards the north-northwest. The red buildings in the photo is the Bear Basin Farmstead. 

Fig 2b


  

Once the temporal and spatial information is known, then it is a matter of reviewing the National Lightning Detection Network (NLDN) data set and observe which cloud to ground lightning flash caused the casualty at the location and time found above. The NLDN data set revealed that a negative cloud to ground lightning flash ( -7 kiloAmpheres) occurred at the geographical location of 38.170712N, 105.289154W. This location is in the immediate vicinity (0.26 miles) of where the fatality occurred on the roadway (38.17161N, 105.29401W). The flash occurred at 2242:11 UTC (4:42:11 pm MDT). 

 

 

Fig 3. Radar image and lightning flash data over a 446 square mile area centered on the location of the fatality. The lightning data in the figure above is the location of all the lightning flashes which occurred during a 1 minute time period between 2242:00 and 2242:59 UTC. Only one flash occurred during this 1 minute time period (marked by a white “-“ in the center of the image). This flash occurred at 2242:11 UTC.  Click on image for a  larger view.

 
In order to observe the trends in lightning activity over the region prior to the lightning strike fatality, both lightning data and radar data were initially analyzed over a 446 statute square mile (21.1 sm x 21.1 sm) area, centered at the location of where the fatality occurred (fig 4). The time of this analysis was from 2213:00 UTC to 2243:00 UTC (the fatality likely occurred at 2242:11 UTC).

Analysis of this data between 2213:00 UTC and the time of the fatal flash indicated the lightning activity over the region was not all that frequent. A total of 31 cloud to ground lightning flashes occurred over this 400 square mile area during the 30 minute time period. This averages out to be about 1 flash per minute. Figure 4 shows a 30 minute loop of lightning and radar data.

Fig 4. Loop of Radar and Lightning data centered on the location of where the fatality occurred (click on image for larger view). Loop of "1 minute" lightning data" runs from 2213 to 2243 UTC (30 minutes). Radar data is composite reflectivity data from National Weather Service Doppler weather radar KPUX. Note that in the above loop, the "1 minute" lightning data shows all of the cloud to ground lightning that occurred during that one minute time period; i.e., "1 minute lightning plot Wed 22:43" indicates all of the lighting which occurred between 22:42:00 and 22:42:59). In the above loop, The 1 minute lighting plots change every minute while the radar data changes every 4-5 minutes. The reason for this is it takes 4-5 minutes to generate a single composite radar reflectivity image. The "time date stamp" of the radar data denotes the time the radar image began.

Additionally, the data was examined to see how much cloud to ground lightning activity was occurring relative to where the fatality actually occurred. Two areas were examined, the first area was within a 6 mile radius during the 10 minute time period (2232:12 – 2242:12 UTC) up to the time of the fatal flash (Fig 5), while the second area looked at the lightning activity that occurred within a 10 mile radius during the 30 minute time period (2212:12 – 2242:12 UTC) up to the time of the fatal flash (Fig 6).

 

 

Figure 5: Plot of Cloud to ground lightning activity within a 10 mile radius of the fatality location between the time of 2212:12 UTC (shown as “0:30”) and 2242:12 UTC (shown as 0:00). The flash immediately above the “0:00” is the flash which caused the fatality.

 

 


 

 

 

Figure 6: Same as figure 5 but within a 6 mile radius of the fatality location between the time of 2232:12 UTC (shown as “0:10”) and 2242:12 UTC (shown as 0:00). The flash immediately above the “0:00” is the flash which caused the fatality. See figure 7 for actual locations of these flashes.

 


 

 

 

 Figure 7. Topographic map showing the location of all of the cloud to ground lightning flashes within a 6 mile radius and within 10 minutes of the fatal flash. The numbers next to the pins show the time (in minutes:seconds) prior to the fatal flash.

 

Figure 5 indicates a total of 25 cloud to ground lightning flashes occurred within a 10 mile radius 30 minutes prior to the fatal flash. Most of these flashes occurred between 3 and 6 miles away.

Figure 6 and 7 shows the CG lightning activity within a 6 mile radius 10 minutes prior to the fatal flash. A total of 6 cloud to ground flashes occurred prior to the fatal flash. All of these flashes prior to the fatal flash occurred generally north of the location of the fatality.

Radar data (Fig 4) during the 30 minute time period prior to the fatal flash showed a thunderstorm over the region which was moving southeast at 15 mph; the thunderstorm was weakening with time. 

Discussion

On 3 July 2008, a 16 year old male, Landon Dillard, was struck and killed by a lightning flash while riding a mountain bike on Custer County road 271 approximately ½ mile (0.6 mi) north-northwest of CO highway 96. He was riding with 4 others at the time of the flash. None of the other 4 riders were injured by the flash, although one of the riders did feel the electrical current from the flash.

From a lightning safety perspective, could anything have been done to prevent this tragic event? From eyewitness accounts of the event, lightning was observed prior to the teen being struck. One of the cyclists who was immediately behind Landon observed a flash as he was turning south onto county road 271 from county road 260 (see Fig 1). The eyewitness stated “The flash seemed to be 2-3 miles away to the north”. Based on the NLDN data shown in figure 7, this could have been either one of the flashes that occurred at 5:05, 5:06 or 3:22 seconds prior to the fatal flash. In addition to the lightning, eyewitnesses reported it was raining prior to the fatal flash. 

The cloud to ground lightning activity was infrequent in this incident. Figures 6 and 7 showed only 6 flashes occurred within a 6 mile radius 10 minute prior to this fatality. This is about 1 flash every 2 minutes. Why did a storm which produced not much CG lightning cause such a tragic event? The reason may be that the riders were lulled into a false sense of security by the fact that the storm was producing so little CG lightning activity. One of the riders mentioned “None of us considered the situation to be one of a life threatening nature any more than a ride on the road with traffic”. 

Sadly, this scenario is not all that uncommon. Numerous other studies of people struck by lightning in Colorado show a similar conclusion, in that storms which produce infrequent cloud to ground lightning activity are the ones that cause the injuries and fatalities.

The lightning safety community recommends that if you can see lightning, or hear thunder, that you should not be outside. There is simply NO PLACE that is “safe” when you are outside when lightning is occurring in the area. (see: 

 http://www.lightningsafety.noaa.gov/outdoors.htm

If you are about to depart for a bicycle trip (or any outdoor activity for that matter), and if you can either see lightning or hear thunder, OR if thunderheads are building overhead, you should remain inside and wait until 30 minutes after the last rumble of thunder or until the thunderheads move away. 

If you do begin your trip and thunder is heard or lightning is observed, you should immediately find safe shelter (either turn around and get back to where you came from, or find a safe shelter from the storm). 

If safe shelter is nowhere to be found, then you should get off the bike and get as low as possible and wait out the storm. 

It should be noted that the bike the teen was riding had nothing to do with the fact that he was struck by lightning. The reason why he was struck was simply due to the fact that he was outside when cloud to ground lighting was occurring in the area. 

Additional Outdoor Lightning risk reduction recommendations can be found either here... here ... here or here

 

Return to the Colorado Lightning Resource Page

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