The 1971 Carpenters’ Blizzard: 'Weather Technology ‘Now and Then’
What do The Carpenters—the blockbuster singing duo of the 1970’s—have to do with a record-shattering blizzard in the Great Plains that occurred 50 years ago this month? And how has our ability to nowcast and warn of violent tornadoes and blizzards changed in the intervening five decades?
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| Daily Weather Map, 6am CST, February 21, 1971 |
The February 20-22, 1971, "Carpenters Blizzard" established records that still stand, including the State of Oklahoma’s single storm snowfall record (36 inches at Buffalo) and Wichita’s single storm record (12 inches). Wind gusts of 50 to 70 mph across the southern High Plains caused peak drifts of more than 25 feet. The drifts necessitated two weeks of desperate National Guard airlifts of hay to tens of thousands of cattle cut off from ranchers in Texas, Oklahoma and Kansas. In 2017, KOCO-TV in Oklahoma City called it “the most intense winter storm to ever hit the Sooner State.”
In addition to the fierce blizzard, tornadoes in Louisiana and Mississippi killed 123. Those tornadoes included Louisiana’s only F-5 (ever). An F-4 tornado threw five victims from their home into a bayou. Their bodies were not found for weeks. At one time the Jackson, Mississippi, RAdar REPort (the NWS's pre-Doppler radar teletype summary of what was depicted by their radars) carried four “hook” designations simultaneously. Prior to Doppler, a "hook" echo was the single best way to determine a tornado may be present.
The national radar chart from 11:35 a.m. CST on February 21 (below) represents conditions at the start of the outbreak. The outline of tornado watch #37, in effect from 10 a.m. to 4 p.m., is depicted by dashed lines and highlighted with an arrow. Minutes after the time of this chart, the first tornado reports came in from far northeastern Louisiana. The first significant (F-2 or greater on the original Fujita Scale) touched down in northeast Louisiana at 3:10 p.m. and promptly moved into the watch area.
1971 Technology
The WSR-57 network was so sparse that a non-existent breaks in the snow pattern were depicted on the radar chart (above). The WSR-57 spacing (Wichita and Garden City, Kansas; Amarillo, Texas, and Oklahoma City) was so course their beams overshot the relatively low precipitation tops. In addition, it was snowing over eastern New Mexico, Colorado east of the Front Range, and southern Nebraska. None of that snow made it onto the radar chart. An inexperienced user, such as a weekend pilot (more common in that era than now), would have greatly underestimated the geographic extent of the snow.
At that time, radar was analog in black and white, and there was no practical way to get a quality signal or picture from one location to another. Radar image remoting2 would not be invented for another six years. The only graphic representation was plots of teletype RAREPs that came via the national meteorological facsimile network (NAFAX). That data was nearly an hour old by the time it arrived. The bandwidth of NAFAX was so low that only about two-thirds of the hourly charts could be transmitted each day.
Jackson, Mississippi, WSR-57 radar image from 4:20 p.m. CST on February 21, 1971.Three tornadoes were in progress northwest of Jackson at this time.
The available data was better at the Jackson, Mississippi, NWS office. The photo above depicts the black and white radar image at 4:20 p.m. when there were three tornadoes in progress. The image in Figure 2 is an improvement over the radar displays in that era. It was created using a camera positioned above the radar scope with a hood that kept light out, allowing the camera shutter to be open for the entire 360-degree sweep. This produced a photograph of all the echoes on the screen. The meteorologist using this had to deal with the storms fading on the display almost immediately after the radar “swept” them. For that reason, radars were operated in dark rooms, which made tracking spotter reports, typing warnings, and communicating information even more challenging. I began nearly daily use of black and white radar three months later and can attest how difficult it was to pick out hook echoes and other important features.
Forecasting the Storm
In 1971, I was a freshman in the University of Oklahoma (OU) School of Meteorology. Like all meteorology schools of that era, OU’s Felgar Hall had a 24/7 “map room” with loud teletypes and a loud wet paper meteorological NAFAX machine. Students could hand-plot surface charts, upper air charts, or whatever data they wished. In 1971, OU’s meteorology department did not have access to radar.
I arrived in the map room around 11 a.m. on February 21 It was as crowded with students as I had ever seen it including legendary future meteorologists like Al Moller and John McGinley. The excitement level was high as were the volumes of voices due to both excitement and frustration because we were certain this was a major, or even unprecedented, event. The frustration was because it was impossible for us—or any organization that needed to track the weather in real-time on a national or regional basis (e.g., airlines like TWA, Braniff or Southern Airways that served the affected areas)—to fully understand the extent and intensity of the storm. We students were shouting, “four flake snow at Gage (Oklahoma),” which was a reference to the diamond-shape arrangement of asterisks plotted on a weather map from a report of heavy snow, or “hook reported from Jackson.”
For meteorologists: The synoptic-scale cyclone developed in Texas ahead of a negatively tilted trough at 500 millibars (mb). The blizzard was well to the northwest of the path of the surface low; farther than one might have expected. At 12 UTC Sunday, February 21, there was a 996 mb surface low near Waco (weather map). It moved north-northeast and intensified to 990 mb 24 hours later in central Missouri at 12 UTC Monday. The orientation of the precipitation around the low shifted as the warm and cold fronts occluded. The change in orientation of the snow field prolonged the duration of the snowfall. The cold front drawn on the Sunday map was actually the dry line (which was not understood in 1971). The cold front was about 100 miles to the west. By 12 UTC Monday, thundersnow was reported from eastern Nebraska to western Iowa. It is likely that convective snow occurred farther southwest the previous day but that could not be ascertained by the available data.
Roads were closed for days throughout the region. In Wichita, mail service was suspended on Monday, February 22, and even beyond in some parts of the city. It is still considered to be the city’s worst blizzard. My recollection is that the intensity of the blizzard was not adequately forecast. That seems to be confirmed by the fact the Sunday Wichita Eagle on the 21st did not include a news story forecasting a major snowstorm.
The storm was the lead story Monday’s Eagle (February 22). The Monday headline of The Great Bend Daily Tribune was “Storm of the Century Immobilizes Kansas.” The Hutchinson News lead story Monday was “Wild Blizzard Buries Entire State.” At the bottom of its front page was a smaller headline “Twisters Kill 21 in the South.” Tragically, that was a serious understatement.
The tornadoes occurred near a warm front (weather map above). The National Severe Storms Forecast Center’s watches did a fine job of alerting the public ahead of the event with the first watch issued at 10 a.m. (radar map). According to the after-event Service Assessment (SA), the local NWS offices did an outstanding job with the warnings. Still, 123 people died because, the assessment found, the warnings were often not received by those that needed them and that many homes in the Mississippi Delta did not have basements. I would add that the late Sunday morning timing—with people sleeping in or occupied by going to church—would also be a reason why the information was not received on a timely basis. Some of the SA’s recommendations involve challenges we face today:
⦁ Aids and techniques should be developed to automate the composition and dissemination of watch and warning bulletins to the greatest possible extent.
⦁ The field investigation of all major tornadoes should include an early aerial reconnaissance survey to determine storm paths more accurately.
⦁ Public safety authorities should be encouraged to develop distinctive warning signals to warn of approaching tornadoes and particularly the immediate need to take cover.
The Carpenters
While the blizzard was in progress, The Carpenters were struggling to get from St. Louis to a concert at Southwestern Oklahoma State University scheduled for Monday night the 22nd.
The group’s blockbuster hits “Close to You” and “We’ve Only Just Begun” were released the year before and “For All We Know” was No. 12—on its way to No. 1 on the Billboard Hot 100—the week of the blizzard.
While the western Oklahoma snow amounts were not as heavy as they were in the Panhandle, travel was highly difficult. While the motto of show business is “the show must go on,” their struggle was such that I have been able to confirm that Richard Carpenter still has a distinct memory of the event fifty years later.
Richard Carpenter began their concert in Tulsa on the 23rd by telling the audience, “We nearly didn’t make it tonight because we were struggling to get out of town due to a blizzard at Northwestern State University.” I spoke with Karen Carpenter (I was covering the Tulsa concert for KGOU-FM in Norman) that night after the concert. She told me the trailers they were towing were swaying in the wind and it was hard to stay on the road.
Technology Today
Fifty years later,
⦁ There would almost certainly be a blizzard warning for the storm. A winter storm watch would have been issued two days before. It is likely the Carpenters would have known what they were driving into (they ended up flying from St. Louis to Oklahoma City and driving the rest of the way).
⦁ The tornado watch would likely have stated this was a “Particularly Dangerous Situation."
⦁ The morning convective outlook which forecast a “few” severe thunderstorms (equivalent to today’s “slight risk”) would likely have forecasted a “moderate” or “high" risk.
⦁ The tornado warnings, since they resulted from supercellular storms, would be smaller in size and equally timely. The smaller size is desirable to limit geography-related false alarms.
⦁ In addition to the tornado sirens and radio warnings in 1971, television stations would be in wall-to-wall coverage, NOAA All-Hazards Radio would trigger, and apps from commercial companies would trigger based on the user’s proximity to danger as determined by GPS using storm-based polygons.
⦁ A half-century after this storm meteorology still struggles at times to effectively communicate forecasts of extreme weather and to engender public response.
These products and procedures are just a small sample that show how weather science has advanced in the last 50 years.
NOTES
- “Radar image remoting” was a term coined by the late Steve Kavorous who invented a device to send a color radar image from one of his devices to another. It was a giant step forward in meteorology.
- In 1977, Southern Airways would suffer a major thunderstorm-related crash (63 fatalities) in a radar gap in northwest Georgia.
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