Why Two Tornadoes That Happened In 1948 Are The Most Important In US History

What would happen on the evening of March 20, 1948 – in an era before Doppler radar, satellites, and computer model guidance – would rattle even the most hardened, experienced forecaster at the time.

Stationed at Tinker AFB on the southeast side of Oklahoma City were two Air Force meteorologists, Maj. Ernest Fawbush and Capt. Robert Miller.

On duty that evening, Miller initially issued a base warning for wind gusts up to 35 mph, but no thunderstorms. 

Just after 9 p.m. local time, weather stations southwest of Tinker AFB reported thunderstorms.

"The sergeant began typing up a warning for thunderstorms accompanied by stronger gusts even though we were too late to alert the base and secure the aircraft," Miller wrote in an account of that event. 

By 9:52 p.m., severe thunderstorms had hammered Will Rogers Airport, southwest of Tinker AFB.

"To our horror, they reported a heavy thunderstorm with winds gusting to 92 miles per hour and, worst of all, at the end of the message, 'tornado south on ground moving NE (northeast)'," Miller recounted.

Eight minutes later, an F3 tornado roared through the base, demolishing 52 aircraft. At the time, it was the costliest tornado in state history, with damage estimated over $10 million.

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The 'Quintessential Event' of Severe Forecasting

The next day, the Tinker Base Weather Station was directed to investigate whether this type of event could be predicted as part of an overall severe weather safety plan for the base.

Before then, public tornado alerts were banned for fear of causing unneeded panic.

When analyzing surface and upper-air data from other outbreaks, Fawbush and Miller noticed large-scale weather patterns common to each event.

A few days later, on the morning of March 25, the pair noticed that a similar weather pattern was setting up that day and concluded that a tornado threat existed again in central Oklahoma that afternoon.

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Then it was a question of confidence.

After consulting Fred Borum, commanding general of the Oklahoma City Air Material Area, a forecast for "heavy thunderstorms between 5 and 6 p.m." was issued for the base.

"You are about to set a precedent," Gen. Borum told the men.

Borum then asked, "Are you going to issue a tornado forecast?"

Imagine being in Fawbush and Miller's shoes. The odds of a tornado striking the same place twice in five days is extremely low, much less, say years or decades. 

(MORE: Oklahoma City's Notorious Tornado History)

After some understandable queasiness, at 3 p.m., Fawbush and Miller issued what was the equivalent of today's tornado watch for the base.

Both meteorologists worried this forecast would bust, hurting public confidence in weather forecasts and their forecast careers.

The base prepared by moving personnel and aircraft to hangars.

Just after 6 p.m., a tornado touched down at Tinker AFB. It caused $6 million in damage at the base, but no injuries were reported.

The first operational tornado forecast was a success.

Fawbush and Miller would go on to issue additional tornado forecasts with amazing accuracy for the mid-20th century.

"Of 75 tornado forecasts issued by the Fawbush-Miller method, 67 have been verified by teletype messages, newspaper clippings and highway patrol reports," according to a Tinker AFB press release.

Their success prompted the Weather Bureau, now known as the National Weather Service, to establish the Severe Weather Unit in 1952.

This unit, later renamed the National Severe Storms Forecast Center and now known as the Storm Prediction Center, began issuing its first severe weather outlooks in 1953.

You have to wonder where severe weather forecasting would be today if it wasn't for the twin Tinker tornadoes.

"The amazing coincidence of multiple tornadoes hitting a military installation, where, in retrospect, just the right players happened to be stationed is perhaps the preeminent and quintessential event of operational severe storm forecasting," wrote Robert Maddox and Charlie Crisp of the National Severe Storms Laboratory in a 1998 study of the event.

While we still cannot forecast exactly where, or sometimes if, tornadoes will track on a given day, Fawbush and Miller's groundbreaking forecast proved general conditions favorable for severe weather could be forecast ahead of time.

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The number of lives saved from the enhancement of these severe weather forecasts, watches, warnings, and improved technology over many decades is impossible to estimate.

Jonathan Erdman is a senior meteorologist at weather.com and has been an incurable weather geek since a tornado narrowly missed his childhood home in Wisconsin at age 7. Follow him on Facebook and Twitter.