Causes
The heat wave began in June when a strong high pressure ridge began to build in the central and southern United States allowing temperatures to soar to 90 °F (32 °C) almost every day from June to September. The high pressure system also acted as a cap on the atmosphere inhibiting the development of thunderstorm activity leading to exceptionally severe drought conditions. The heat wave broke only when decaying Hurricane Allen disrupted the prevailing weather pattern.
Read more about this topic: 1980 United States Heat Wave