On This Date in History: Any Louisvillian who was here on this date in 1974 does not need to hear anything more. They don’t need to see raw video from April 3, 1974 to remind them what happened on that day in history. That is true for much of the Ohio Valley. The “Super Outbreak” of tornadoes of April 3-4 1974 was the greatest such event in recorded history. In less than 18 hours 330 people were killed and some 900 square miles in 13 states suffered tornado damage. Some sources say that at one time during the event, 15 tornadoes were on the ground at once. Given the size of the US, that doesnt seem too remarkable to me. I’ve seen photos of 3 tornadoes in one area of one Texas county simultaneously. What is remarkable is that of the 148 tornadoes reported in those 13 states, nearly 19% were big boppers. Twenty two were reported to be F4 and six were F5. That means that if a tornado came to your town that afternoon, there was about a one in five chance you were getting smacked by a tornado that represented the most powerful concentration of force on the face of the earth.
In total energy, a hurricane far outpaces a tornado. But for a brief period in such a relatively small area, an F-5 tornado can have winds pushing toward 300 mph and creates total destruction. They don’t happen often but to have 22 on one day is quite rare. Of course, the twister that hit Breckenridge county and Louisville was one of those. Folks have told me about the one in Madison, IN. I guess given the destructive power of the storms, perhaps it is also rather unbelievable that only 330 died given that about 50,000 were directly affected. If you scroll back a few days to March 27, you will see that the 1890 tornado in Louisville took 120 lives and it wiped out much of the business district during the night when people weren’t there. No doubt the Louisville total in 1890 would have reached or even surpassed the 1974 national toll had it happened in the day time.
A big question that arises is how this all came about. I’ve provided a link to a Why the Outbreak Occurred. It is pretty helpful. Not all storms produce tornadoes as there are specific parameters or ingredients necessary to produce storms, including but not exclusively supercells, and that doesn’t happen all the time. When one considers the number of thunderstorms on the planet, supercells are relatively rare. But they can and do occur and tornadoes have been reported all over the world and have been reported in every state. But the topography of the United States, oriented with the Rocky Mountains to the west, the Great Plains with a clear shot to the polar region, the Mexican Desert to the Southwest and the Gulf of Mexico to the South, creates perhaps the most consistent breeding ground on earth for tornadic thunderstroms. This is why it has become known as “Tornado Alley.” If you click on the map to the left from Penn State University, you will be directed to a full Tornado Alley explainer, though I would have expanded their definition of the alley a bit farther north. Study of the 1974 event has continued an in 2004, Risk Management Solutions produced this detailed analysis of the meteorological circumstance that created the event.
Anyone who lives in Louisville today and was around in 1974 can tell you where they were when the tornado blew through town. This link has historical radio broadcasts from Louisville. If you scroll down you will find WHAS radio coverage of the 1974 tornado. Within those reports you may find those broadcast (or at least a reference) by the radio station’s helicopter pilot who was the eyes and ears of the city. He is credited with saving lives. A transcript of the conversations as well as a brief bio of pilot Dick Gilbert can be found here. Remember, this was prior to all of the intricate warning systems of today and the fancy superduper skywarn doppler tracking 3000 radars on TV.
Here’s a cool link with more details and photographs broken down by state as well as eyewitness accounts:
Technology has brought us many advancements, though often there is some downside to technological breakthroughs. Take the computer for instance…some say that kids are getting fat because they don’t go outside and play any more, preferring to stay indoors and play computer games. But thats a topic for someone elses blog. In this case, technology has greatly enhanced warnings to the point that a big ole outbreak like 1974 resulted in far fewer fatalities than would have happened in the past. You’re never going to eliminate them because of the sheer power involved in the storms. But, you can do the best you can. Thing is, in recent years, fatalities have increased so some work needs to be done. Perhaps it’s the Paris Hilton syndrome: Over Exposure.
Weather Bottom Line: The forecast is pretty much holding to what I said yesterday. Snow White and I had a very nice walk Friday evening and it seemed as if the moisture content had increased, yet the dewpoints were only in the upper 30’s. Hmm…pretty dry. I don’t think we can really moisten up the atmosphere sufficiently by Saturday afternoon to really make any storm activity all that significant. But, the lapse rates remain very steep and elevated storms could be an issue. The main energy with this activity will be well to the north of our area but we will be getting stuff in here by late afternoon. Possible for t’storms? Yes? Biggest threat would be small hail or gusty winds but the dynamics are best to our west, which is why the NWS has the 5% chance to our west.
As I mentioned yesterday, it looked to me that, Sunday would be nice but that the front would come back as a warm front on Monday. Hence, a chance of rain. Then our temperatures soar back to the low to mid 80’s on Tuesday and Wednesday. I would think that Wednesday afternoon or evening may be a better chance for some action around here. Don’t look for a repeat of April 3,1974. Odds are, it won’t even be that big of a deal. But, it looks potentially more interesting to me than this weekend.