Before I can tell this story, I need to supply a little bit of technical background or you won't understand it. During my teenage years and before, the Twin Cities Metro area had a telephone "dating service" similar to Internet Chat Lines of today. We called it the Jam Line, and I have since discovered that some cities in other parts of the country had them too, but called them by a different term: "Beep Line." Anyway, the cause of the Jam Line was the telephone company's building of the new Electronic Switching (ESS) that we use today. In order for ESS to work correctly, it had to be built in parallel to the old mechanical switching used in the 1950's - 1970's. This created a Loop in the telephone lines allowing people to talk to each other when getting a Busy Signal. Us teens would dial the local radio station's request line, which was always busy, and get the Jam Line; where one would shout out their telephone number between the beeps of the busy signal and the guys/girls would call each other back. Now that you've got the background here's the story:


It was about 8:30 pm on April 26, 1984. A teenage girl was standing in a phone booth in the parking lot of the SuperAmerica gas station on 37th Ave. NE, in Minneapolis, MN talking on the Jam Line, when suddenly the telephone line went dead, then was followed by some clicking sounds, went dead again, and just as suddenly the Jam Line was back on. Moments later the power went out all around her, then an F-3 tornado hit the Apache Plaza Shopping Mall about a 1/2 mile away. The resulting damage would trigger the eventual bankruptcy and demolition of the mid-sized indoor mall built in 1961.

For days afterwards the local evening News casts would focus on how there were no warning sirens sounded before this tornado struck the mall. There was a lot of public outcry for a better system to activate the civil-defense warning network. It turned out that the civil-defense sirens were triggered by telephone line, and for some reason the system had failed in the 781/788/789 telephone prefix areas. The sirens worked fine in other areas of the city. The Weather Service was baffled.

The Jam Line that existed on the 781/788/789 prefix was the last ever in the Twin Cities, MN area. It was shut down in 1984, about a month after the tornado, but not before I talked to the teenage girl who was in the phone booth that stormy night. She was one of the last girls I ever talked to off of the Jam Line, and she talked about this strange story of how the tornado had momentarily knocked out the Jam Line, and how she was so close she could see a "green-glow" in the darkness traveling along the ground towards Apache Mall. To her, the NWS, and the TV News Reporters, there was no explanation for the failures that night. To me and a select few others, we knew exactly what had happened.

One of my friend’s mom’s was a NorthWestern Bell Telephone Operator. Both my friend and I were heavily into the Jam Line. We had been told by his mom that the telephone company didn’t like the Jam Line because with so many people calling into a certain prefix, it would over-load the circuits, crash the relay switching station, and block in-coming calls. The phone company would have to try and reroute traffic, but they could only do so much. That teenage girl told me the Jam Line was very busy that night and there were about 20 people screaming on the Line. She had been a bit frustrated trying to dial in because it was hard to get through. It didn’t take an Einstein to figure out what had happened, but the phone company kept it quiet. The Jam Line had overloaded the circuits and blocked the trigger signal for the warning sirens in the area.

Many residents and shoppers lives were put at risk that night because they had no warning. No one could have ever predicted that the Jam Line would have caused such a mess. These events are a true story; but the conclusions are purely speculation on my part.

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