50th Anniversary of the April 3-4, 1974 Super Outbreak

[CheeselandSkies]

Can anyone think of another situation in which a settlement, town, or city got impacted by multiple (E)F5s on the same day? As far as I know only Tanner holds the distinction. To me this is one of the most astonishing statistics in relation to the 1974 Super Outbreak.

They're not officially F5s, but didn't some communities in northwest Indiana and southern Lower Michigan get hit by two violent tornadoes during Palm Sunday 1965? That's the only other possible instance I can think of, although other outbreaks have impacted the same community with (E)F3+ in the same day (May 3, 1999 - Mulhall, OK F4 followed by Crescent-Mulhall area F3; April 27, 2011 Cordova, AL morning and afternoon). The (E)F5 rating is so rarely achieved in the first place it's a near impossibility, so the fact that it occurred at all is a testament to how exceptional the Super Outbreak was.

 

[tennessee storm chaser]

They're not officially F5s, but didn't some communities in northwest Indiana and southern Lower Michigan get hit by two violent tornadoes during Palm Sunday 1965? That's the only other possible instance I can think of, although other outbreaks have impacted the same community with (E)F3+ in the same day (May 3, 1999 - Mulhall, OK F4 followed by Crescent-Mulhall area F3; April 27, 2011 Cordova, AL morning and afternoon). The (E)F5 rating is so rarely achieved in the first place it's a near impossibility, so the fact that it occurred at all is a testament to how exceptional the Super Outbreak was.

From the pics I can remember seeing and going back and studying this event. Just going by the ground scouring was several Ef5 s with the suoer
Outbreak 74

 

[Casuarina Head]

They're not officially F5s, but didn't some communities in northwest Indiana and southern Lower Michigan get hit by two violent tornadoes during Palm Sunday 1965? That's the only other possible instance I can think of, although other outbreaks have impacted the same community with (E)F3+ in the same day (May 3, 1999 - Mulhall, OK F4 followed by Crescent-Mulhall area F3; April 27, 2011 Cordova, AL morning and afternoon). The (E)F5 rating is so rarely achieved in the first place it's a near impossibility, so the fact that it occurred at all is a testament to how exceptional the Super Outbreak was.

Re: the Super Outbreak in northwestern Alabama: I think there were probably many more tornadoes than officially confirmed, especially along and near the MS/AL border. Radar imagery posted by the NWS Huntsville on its Super Outbreak page shows a number of discrete or semi-discrete cells with well-defined hook echoes, crude pre-Doppler technology notwithstanding, trailing the Guin supercell between 8:33 and 10:21 p.m. local time. These cells often crossed the same areas affected by earlier storms such as the Guin supercell. Given the very favourable dynamics still in place, I would think that these kinds of signatures would be associated with additional, maybe even significant, tornadoes that were undocumented in official surveys.

The loops over eastern MS/northwestern AL during the afternoon of 3 April actually look similar to the presentation on 27 April 2011, with virtually every cell exhibiting rotation, despite some mergers here and there, and numerous discrete supercells with high tops. Even so, the fact that the 1974 Super Outbreak produced many more violent tornadoes, some on a near-parity with the strongest of the 2011 Super Outbreak, over a much wider geographic extent signifies to me that the 1974 outbreak is still on a level above that of 2011, though both were extraordinary by just about every metric. Storms like Brandenburg, Guin, Xenia, and both Tanner F5s were extremely violent tornadoes, and there were a number of other possible F5s on that day, too, besides the official six (Dr. Fujita) or seven (NWS).

 

[wasatch]

Re: the Super Outbreak in northwestern Alabama: I think there were probably many more tornadoes than officially confirmed, especially along and near the MS/AL border. Radar imagery posted by the NWS Huntsville on its Super Outbreak page shows a number of discrete or semi-discrete cells with well-defined hook echoes, crude pre-Doppler technology notwithstanding, trailing the Guin supercell between 8:33 and 10:21 p.m. local time. These cells often crossed the same areas affected by earlier storms such as the Guin supercell. Given the very favourable dynamics still in place, I would think that these kinds of signatures would be associated with additional, maybe even significant, tornadoes that were undocumented in official surveys.

The loops over eastern MS/northwestern AL during the afternoon of 3 April actually look similar to the presentation on 27 April 2011, with virtually every cell exhibiting rotation, despite some mergers here and there, and numerous discrete supercells with high tops. Even so, the fact that the 1974 Super Outbreak produced many more violent tornadoes, some on a near-parity with the strongest of the 2011 Super Outbreak, over a much wider geographic extent signifies to me that the 1974 outbreak is still on a level above that of 2011, though both were extraordinary by just about every metric. Storms like Brandenburg, Guin, Xenia, and both Tanner F5s were extremely violent tornadoes, and there were a number of other possible F5s on that day, too, besides the official six (Dr. Fujita) or seven (NWS).

I would argue the opposite - to a degree at least... we know the EF scale is more rigid with higher end ratings, so it's almost certain that rated on the EF scale there wouldn't have been six or seven F5's on April 3, probably three (as Grazulis' updated book seems to indicate, assuming Guin, Brandenburg and Xenia - https://www.tornadoproject.com/book/outbreaks_section.htm) or vice versa on the old F scale we'd have had 6-7 F5's from April 27... regardless of which order one puts them in they're both head-and-shoulders above any other outbreaks.

 

[MNTornadoGuy]

I would argue the opposite - to a degree at least... we know the EF scale is more rigid with higher end ratings, so it's almost certain that rated on the EF scale there wouldn't have been six or seven F5's on April 3, probably three (as Grazulis' updated book seems to indicate, assuming Guin, Brandenburg and Xenia - https://www.tornadoproject.com/book/outbreaks_section.htm) or vice versa on the old F scale we'd have had 6-7 F5's from April 27... regardless of which order one puts them in they're both head-and-shoulders above any other outbreaks.

Agreed especially since the original F-scale didn't take construction quality into account as much as the EF-scale. For example photographs from Xenia show the slabbed homes were unanchored and probably would only get EF4 today.

 

[Casuarina Head]

I would argue the opposite - to a degree at least... we know the EF scale is more rigid with higher end ratings, so it's almost certain that rated on the EF scale there wouldn't have been six or seven F5's on April 3, probably three (as Grazulis' updated book seems to indicate, assuming Guin, Brandenburg and Xenia - https://www.tornadoproject.com/book/outbreaks_section.htm) or vice versa on the old F scale we'd have had 6-7 F5's from April 27... regardless of which order one puts them in they're both head-and-shoulders above any other outbreaks.

I think at least Tanner #1 would qualify as EF5 as well, which would bring the total to at least four. Depauw and Sayler Park have always been the iffiest, but we do not have very detailed photographs of the highest-end DIs, especially in the case of Depauw, so I don’t think that we should assume that these tornadoes would not qualify as EF5s. People were even doubting that Xenia deserved an F5 rating on the old scale until much more detailed attestation of its violence came in. Guin has lived up to its reputation as an extremely violent F5, even if the most extreme claims (i.e., about foundations being swept away) unfounded.

Obviously standards of construction were often subpar in several of the worst-hit areas in 1974, but this can be compensated by the inclusion of contextual evidence. Context fully supports or lends credence to EF5 ratings being applicable in the cases of Guin, Brandenburg, Xenia, and at least one of the Tanner tornadoes. Some of the F4s on 3 April may also have been capable of F5 and even EF5 damage, had they hit conventional DIs such as well-built structures. Plus, the environment in the vicinity of the strongest tornadoes in 1974 was supportive of high-end events, even potential EF5 tornadoes.

So I think that 1974 likely featured four or five actual or potential EF5s. Xenia may have hit many unanchored homes, but it also produced extreme granulation, localised scouring, and intense debarking of low-lying shrubbery, not to mention very high-end wind-rowing. I think there is enough evidence that Brandenburg and Guin would qualify as EF5s. As far as Tanner is concerned, contextual DIs such as scouring, debarking, and vehicular damage, not to mention the well-pump being pulled out the ground, would hint that EF5 damage was certainly possible.

 

[David in SW Blount]

They're not officially F5s, but didn't some communities in northwest Indiana and southern Lower Michigan get hit by two violent tornadoes during Palm Sunday 1965? That's the only other possible instance I can think of, although other outbreaks have impacted the same community with (E)F3+ in the same day (May 3, 1999 - Mulhall, OK F4 followed by Crescent-Mulhall area F3; April 27, 2011 Cordova, AL morning and afternoon). The (E)F5 rating is so rarely achieved in the first place it's a near impossibility, so the fact that it occurred at all is a testament to how exceptional the Super Outbreak was.

And the Cordova tornado path cores crossed over each other right in the middle of Cordova.

 

[Tennie]

They're not officially F5s, but didn't some communities in northwest Indiana and southern Lower Michigan get hit by two violent tornadoes during Palm Sunday 1965? That's the only other possible instance I can think of, although other outbreaks have impacted the same community with (E)F3+ in the same day (May 3, 1999 - Mulhall, OK F4 followed by Crescent-Mulhall area F3; April 27, 2011 Cordova, AL morning and afternoon). The (E)F5 rating is so rarely achieved in the first place it's a near impossibility, so the fact that it occurred at all is a testament to how exceptional the Super Outbreak was.

There was an instance where two F5s were filmed merging together during the 03/13/1990 outbreak, though that was over mostly open fields.

Another possible contender would have to be the 04/06/1936 Gainesville, Georgia tornado(es), where reportedly two tornadoes merged right over the city and caused damage rated at F4.

 

[MNTornadoGuy]

They're not officially F5s, but didn't some communities in northwest Indiana and southern Lower Michigan get hit by two violent tornadoes during Palm Sunday 1965? That's the only other possible instance I can think of, although other outbreaks have impacted the same community with (E)F3+ in the same day (May 3, 1999 - Mulhall, OK F4 followed by Crescent-Mulhall area F3; April 27, 2011 Cordova, AL morning and afternoon). The (E)F5 rating is so rarely achieved in the first place it's a near impossibility, so the fact that it occurred at all is a testament to how exceptional the Super Outbreak was.

Fridley got hit by 2 (likely 3) F4s during 5/6/1965.

 

[Furynado]

Hello everybody,

I suppose it remains highly debatable whether the April 3, 1974 or April 27, 2011 tornado "super" outbreak was more violent, but as someone who was born in 1986 and therefore did not see the live developments of the 4/3/74 event in person I remain more fascinated by the first event. The aspect of the 1974 event that stands out to me is the fact that it covered larger territory extending south to north from Alabama to Ohio and Indiana. As for how it appeared on radar, I believe it was largely similar to the 2011 outbreak with a broad expanse of massive individual rotating supercells (from the primitive radar images available online).

Another aspect of 1970s meteorology that very much interests me is the broadcasting methods used for warnings. An interesting account I read from the Louisville tornado is that WDRB had "Presto the Clown", Bill Dopp, read the Tornado Warning for the 1974 tornado. Supposedly, upon having heard of the tornado/associated warning (which I believe occurred during his regularly-scheduled program, he became scared (naturally) and then said, "Boys and girls, I want you to find your parents and tell them to come to the television set. I have something very important to tell them!" and then he (or one of his colleagues) held up a "Tornado Warning" slide and he proceeded to read the warning. I'm not sure exactly what the slide looked like, but I believe it had a red background with the lettering "TORNADO WARNING" perhaps in black, or perhaps "TORNADO" was written in black lettering whereas "WARNING" was presented in white. Does anyone have any knowledge of this?

As for the general presentation of warnings at that time (during the 1970s), I don't believe most stations had live accounts ("wall-to-wall" coverage) as they now do, but that instead they typically would display a "Tornado Warning" slide every 5 or 10 minutes during the duration of a Tornado Warning and have a voiceover (perhaps also EBS activation later on). While I believe some stations took their artistic liberties with their weather (Severe Thunderstorm, Tornado, etc.) warning slides, I think the NWS had some standard slides they distributed to TV stations - while I believe there were different versions, they generally had a red background for Tornado Warnings. Here is a mockup I created of one of the Tornado Warning slide versions based on what I've seen online (although I haven't yet found any actual live recordings of this Tornado Warning slide) - does anyone who was alive and watching TV in the '70s recall having seen something like this?:

 

[David in SW Blount]

Hello everybody,

I suppose it remains highly debatable whether the April 3, 1974 or April 27, 2011 tornado "super" outbreak was more violent, but as someone who was born in 1986 and therefore did not see the live developments of the 4/3/74 event in person I remain more fascinated by the first event. The aspect of the 1974 event that stands out to me is the fact that it covered larger territory extending south to north from Alabama to Ohio and Indiana. As for how it appeared on radar, I believe it was largely similar to the 2011 outbreak with a broad expanse of massive individual rotating supercells (from the primitive radar images available online).

Another aspect of 1970s meteorology that very much interests me is the broadcasting methods used for warnings. An interesting account I read from the Louisville tornado is that WDRB had "Presto the Clown", Bill Dopp, read the Tornado Warning for the 1974 tornado. Supposedly, upon having heard of the tornado/associated warning (which I believe occurred during his regularly-scheduled program, he became scared (naturally) and then said, "Boys and girls, I want you to find your parents and tell them to come to the television set. I have something very important to tell them!" and then he (or one of his colleagues) held up a "Tornado Warning" slide and he proceeded to read the warning. I'm not sure exactly what the slide looked like, but I believe it had a red background with the lettering "TORNADO WARNING" perhaps in black, or perhaps "TORNADO" was written in black lettering whereas "WARNING" was presented in white. Does anyone have any knowledge of this?

As for the general presentation of warnings at that time (during the 1970s), I don't believe most stations had live accounts ("wall-to-wall" coverage) as they now do, but that instead they typically would display a "Tornado Warning" slide every 5 or 10 minutes during the duration of a Tornado Warning and have a voiceover (perhaps also EBS activation later on). While I believe some stations took their artistic liberties with their weather (Severe Thunderstorm, Tornado, etc.) warning slides, I think the NWS had some standard slides they distributed to TV stations - while I believe there were different versions, they generally had a red background for Tornado Warnings. Here is a mockup I created of one of the Tornado Warning slide versions based on what I've seen online (although I haven't yet found any actual live recordings of this Tornado Warning slide) - does anyone who was alive and watching TV in the '70s recall having seen something like this?:

View attachment 24535

Yes, I don't remember the NOAA emblem on the bulletin banners specifically, but in Memphis during the 1970's, something similar to this would appear on the TV screen with an alert sound. Sometimes a broadcaster at the TV station would read the alert, but as I recall, often it was the NWS. These would appear for severe thunderstorm alerts also, including watches.

 

[Tennie]

It's unfortunately hard to find old footage of severe weather coverage, especially from the earlier days of television. Sure, there is some footage that has managed to survive (for example, the live coverage of the 1964 Wichita Falls, TX, tornado), but most of the time the tendency was to usually tape over that coverage (videotape back then being fairly expensive, as well as the lack of consideration to the idea that anyone in the future would want to watch this stuff, has led to a lot of early television programs in general being unfortunately lost to the sands of time).

Thankfully, things have gotten better over the years with regards to the preservation of severe weather coverage (especially in the modern era of streaming media).

 

[Furynado]

Yes, I don't remember the NOAA emblem on the bulletin banners specifically, but in Memphis during the 1970's, something similar to this would appear on the TV screen with an alert sound. Sometimes a broadcaster at the TV station would read the alert, but as I recall, often it was the NWS. These would appear for severe thunderstorm alerts also, including watches.

I see - thanks for the info! Do you remember how the alert tone sounded - e.g., did they use the EBS tone or something else? Also, would the background color for other bulletin types be different, or red as well? I've heard they typically used yellow for Severe Thunderstorm Warnings. However, I did find the following recording on YouTube of a Severe Thunderstorm Warning announcement from Omaha's KMTV from 1980 that used a red background:

 

[MNTornadoGuy]

 

[akt1985]

Here is a short audio clip from WJMW AM in Athens, Alabama of one of the F5s going through Limestone County.

 

[Ivanthetornadoenthusiast]

 

[David in SW Blount]

I see - thanks for the info! Do you remember how the alert tone sounded - e.g., did they use the EBS tone or something else? Also, would the background color for other bulletin types be different, or red as well? I've heard they typically used yellow for Severe Thunderstorm Warnings. However, I did find the following recording on YouTube of a Severe Thunderstorm Warning announcement from Omaha's KMTV from 1980 that used a red background:

I don't recall it necessarily being red, and I think each TV station had its own banners and maybe even alert sounds. They were different from Civil Defense alert sounds but similar. Definitely attention grabbing!

 

[MNTornadoGuy]

New TornadoTalk article on Xenia: https://www.tornadotalk.com/the-xenia-oh-f5-tornado-april-3-1974/

 

[CheeselandSkies]

Neither of our major national news partners at work (NBC News, and CNN) have ANY affiliate content available for the 50th anniversary of the Super Outbreak. Zilch. Nada.

Another sad reminder that there are severe weather geeks, and then there's everybody else.

 

[warneagle]

Interesting visualization of the difference in population/density in the areas affected in 1974 vs. the present.