While the National Centers for Environmental Information list the direct death toll from the 1980 heat wave as 1,260, it also notes that the estimated indirect death toll from heat stress may have been as high as 10,000. By comparison, some 6,000 to 12,000 were killed, in various estimates, by the 1900 Galveston Hurricane, the deadliest natural disaster in U.S. history.
Because heat waves do not leave behind a trail of destruction and receive the media attention of many disasters, they are often referred to by scientists as “silent killers.”
You know a heat wave was big if, in Texas, where everything is big, especially hot summers, it sears a deep brand into the record books 40 years later.
It has never been hotter at Dallas-Fort Worth, or extremely hot for as long, as it was in 1980. But it was far more than Texas that suffered in 1980, as a heat wave of unusual size and intensity expanded across much of the South, Midwest and East.
Agricultural losses from the heat wave and associated drought exceeded $60 billion in inflation-adjusted dollars, according to Department of Homeland Security estimates. The poultry industry was particularly hard hit, with millions of birds succumbing to extreme temperatures.
The Centers for Disease Control estimates that an average of 658 people per year die of heat-related illness in the United States, though some experts estimate that number may be over 1,000.
Extreme heat will become an issue in some regions in the days ahead, as a “heat dome” of high pressure continues to develop over the central United States, expanding eastward and northward at times. The full expanse and intensity of the coming heat wave are yet to be determined, but temperatures will certainly be life-threatening in many areas for those without proper shading or hydration.
Washington, through Friday, has already had 15 consecutive days of high temperatures at or above 90 degrees. The record for longest 90-degree streak is 21, last occurring in 1988, but also in 1980. Washington’s record number of days at above 90 was also set in 1980, at 67, then tied in 2010.
Washington’s heat peaked on July 16 in 1980, when it hit 103 degrees, its highest temperature in nearly 37 years. Then there was a second surge of heat in late July and the first half of August.
At the time, summer 1980 was considered the worst U.S. heat wave since 1954, and it has stood the test of time since for the breadth and intensity of its extremes.
Dallas-Fort Worth, no stranger to extreme heat in almost any summer, still has heat records dominated by 1980, including:
- All-time highest temperature, 113 degrees on June 26 and 27.
- Longest streak of days with high temperatures of at least 100, 42.
- Longest streak of days highs temperatures of at least 90, 79.
- Hottest month, based on average temperature, 92 for July 1980.
Every daily record high from June 24 to July 5, plus seven more later in July, still date to 1980 for Dallas-Fort Worth. Since records began in 1898 at the station, now housed at the international airport, five of 10 days with highs of 110 or higher occurred that sizzling summer 40 years ago.
Memphis and Little Rock each recorded its longest streak of 100-plus degree days, at 15 each, in early to mid-July.
The heat wave tended to spread east with time, with Washington’s record 90-degree streak starting in late July and extending to August 14.
Hurricane Allen disrupted the heat some in Texas. Allen, once an extremely powerful Category 5 storm with 190 mph winds, came ashore as a Category 3 storm with 115 mph winds just north of Brownsville on Aug. 10. But 100-degree temperatures occurred in Texas deep into September.
Heat waves are not overly creative in how they develop over the United States. Invariably, a strong high pressure system is present aloft, spreading out over many hundreds of miles at two to six miles up. With weaker atmospheric steering currents in summer, this high moves nowhere fast.
Warm air sinks and compresses underneath the high pressure, heating as it does. Little in the way of convection is able to develop underneath the high, both due to the sinking air and to the tendency for warmer air aloft to strongly cap the atmosphere. So there are few showers or storms capable of providing cooling underneath the high pressure.
Furthermore, days of intense heat heats the surface and dries up vegetation underneath the high, adding an oven-like effect that helps propagate the heat wave.
Around the edge of the high, a “ring of fire” often develops where the pressure and capping are weaker, allowing storms to develop.
Just as the 2012 heat wave was punctuated by the June 29 derecho from the Ohio Valley across the Appalachians and Mid-Atlantic, 1980 had the colorfully named “More Trees Down” derecho from Nebraska to the Delmarva Peninsula on July 4-5, killing six and injuring 63. Wind gusts topping 80 mph occurred in northern Virginia.
(The name relates to a forecaster's father noting that there had been even more trees down at his Indiana farm than in a previous derecho.)
Climate scientists project, and have observed, an increase in the frequency, size and intensity of heat waves as global temperatures warm. Year to year, however, the intensity of a particular heat wave over a given region comes down to details affected by the atmospheric pattern at the time.
After 40 years of rising global temperatures and other notable heat waves, 1980 continues to hold a significant place in our nation’s weather history.
Kevin Myatt writes the Weather Journal column and blog for the Roanoke Times.