Tis the thunderstorm season for much of the country. What to do during a thunderstorm came up on the Surly group, and I would like to share some that info with my Riv bretheren.
Florida has the distinction of suffering the most lightning deaths. The Four-Corner states are a distant second. But thunderstorms can occur anywhere. Even if you are not killed by a lightning strike, your life can be severely altered. It pays to have some knowledge and remain aware. I am a forecaster for the National Weather Service (NWS) in Colorado. Here is the NWS lightning safety recommendations http://www.srh.noaa.gov/jetstream//lightning/lightning_safety.htm Unfortunately in my opinion the NWS is dropping the ball with lightning safety. "When thunder roars go indooors" just doesn't woork for those of us on long bike rides, hikes, etc. The NWS has also thrown out the 6 mile rule. Really if you can hear thunder, you are in danger. To measure lightning distance, use the fact that the speed of sound is roughly 1000ft/sec. Measure time between flash and boom, then divide by 5 to get miles. But better than this, be situationally aware. Get a forecast before you go out, especially if you will be out for many hours or days. I think you will be hard pressed to beat the day to day forecasts from the NWS http://www.weather.gov/ Click on the map to get your local office. Then you can click on their map to get your local area. There is a different forecast for every 2.5km or 5 km, depending on the office. Then when you are out, keep watching the sky. It takes 3 ingredients to build thunderstorms: lift, instability, and moisture. Lift can be produced by mountains, cold fronts, differential heating, or in Florida's case sea breezes. As for moisture and instability, watch the sky for any cloud that has vertical growth, especially in the morning: cumulus http://www.usatoday.com/weather/wcumulus.htm altocumulus castellanous (ACCAS) http://tinyurl.com/23xmvmk cirrocumulus http://mmem.spschools.org/grade5science/weather/cirrocumulus.html If you see the cumulus, towering cumulus, or ACCAS before 11 AM, chances are you have sufficient moisture and instability for afternoon thunderstorms. Adjust your behavior with that in mind. And you don't have to be underneath a thunderstorm to get struck by lightning. Lightning bolts off the sides or tops of thunderstorms can strike many miles away from the base and are some of the most powerful lightning stikes. http://www.crh.noaa.gov/pub/ltg/crh_boltblue.php If somehow you still screw up and get yourself near a sparking thundertorm, stay away from high trees, poles, exposed mountain ridges, water. Then get to lower ground as fast as possible. Watch out for drainge bottoms though where flash flooding is possible. If things get really bad, lower yourself as much as possible but stay on your feet. You do not want to lay flat and put your heart right next to the ground. CPR is a very effective treament for those who are struck and not breathing. The NWS recommends that if you can hear thunder, you are in danger. And the 30 rule says, stay under shelter until 30 minutes after you last hear thunder. I can say that if I followed that rule, I wouldn't be out for most summer afternoons or early evenings. Lightning safety is about risk analysis and informed choices. To be perfectly safe, you need to very carefully sit on your couch. Of course there are many risks associated with that behavior too! -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To post to this group, send email to rbw-owners-bu...@googlegroups.com. To unsubscribe from this group, send email to rbw-owners-bunch+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en.
