These are the all-time ten hottest weather temperature days recorded in the city of St. Louis, Missouri. The temperature data for St. Louis dates back to 1889.
It can certainly get really hot in St. Louis. The all-time hottest temperature ever recorded in St. Louis is 115 degrees which occurred on July 14, 1954. The hottest temperature ever recorded in the state of Missouri is 118 degrees, which also occurred on July 14, 1954 in Warsaw and Union.
Every single date in the months of July and August in St. Louis have had at least one 100 degree weather temperature day dating back to 1889. In fact, every single date from June 22 through September 9, have had at least one 100 degree weather temperature day.
The earliest date when a 100 degree day occurred in St. Louis was June 1, 1934, when it was exactly 100 degrees. The latest date when a 100 degree day occurred was September 29, 1953, when it was 102 degrees.
 "10 All-Time Hottest Weather Temperature Days in St. Louis (1)")
10 All-Time Hottest Weather Temperature Days in St. Louis
1. July 14, 1954 - 115 degrees
2. July 18, 1954- 112 degrees
3. July 24, 1934 - 111 degrees
T-4. July 12, 1954 - 110 degrees
T-4. August 9, 1934 - 110 degrees
T-4. July 20, 1934 - 110 degrees
T-7. July 14, 1936 - 108 degrees
T-7. August 8, 1934 - 108 degrees
T-7. July 23, 1934 - 108 degrees
T-8. July 28, 1930 - 108 degrees
T-8. July 22, 2017 - 108 degrees
T-8. June 28, 2012 - 108 degrees
The hottest month of the year in St. Louis, Missouri is July, which has a daily average temperature of 88.3 degrees, followed closely by August at 87.1 degrees. The next hottest month in St. Louis is June at 83.2 degrees, and then September which averages 78.8 degrees.
Interestingly, all but two of these high temperatures occurred during a dust bowl year. All of the highest temperatures in the 1930s occurred during the Dust Bowl, but 1954 was also a dust bowl year. The mid 1950s were as dry as the Dust Bowl, but new farming practices that were learned during the Dust Bowl and the planting of trees for windbreaks in the 1930s kept the 1954 dust bowl from being worse.
During the heat wave of 2012, at least the humidity was low and many localities canceled their 4th of July firework shows because of the very hot and dry conditions.
1980 Heat Wave
The heat wave of 1980 began in Texas where 60 people had already died at the start of July before the desert heat wave blew north towards St. Louis. In St, Louis, the heat wave began on July 7, 1980 when the high temperature hit 99 F, and the next day, the high temperature hit 101 F.
The high temperature would break 100 F on nine of the next 14 days, hitting 107 on July 15th, and the summer’s hottest temperature. During that hot summer of 1980, the high temperature in St. Louis would hit 100 or higher on 18 days.
During the heat wave, the daily death toll was rising. On July 11th, military trucks provided truck-size portable air conditioners that pumped chilled air through fat pipes into the hospital windows to the City Hospital, which lacked air conditioning.
The high temperature reached 100 F or hotter on six of the first 10 days of August. By the end of this heat wave, the heat wave killed 153 people in the St. Louis area. Many of those that died were elderly and had no air conditioning and had their windows closed due to fear of being robbed. The state of Missouri had a death toll of 300 from this heat wave.
The worst heat wave ever in St. Louis was in 1934 (during the Dust Bowl) when more then 420 people died. St. Louis has had other serious heat waves, but in recent memory, none worse than the heat wave of 1980.
The heat wave of 1980 is listed as the 5th worst heat wave in United States history. Not only did it affect St. Louis, but also a good portion of the United States. The death toll from the 1980 heat wave was at least 1,700 people, and the economic losses were estimated at $16 billion due to crop losses.
Thankfully today, most homes, even low income homes, have at least a window air conditioner.
For more see 10 All-Time Hottest Weather Temperature Days in Kansas City
10 All-Time Hottest Weather Temperature Days in Chicago
10 All-Time Hottest Weather Temperature Days in Memphis
10 All-Time Hottest Weather Temperature Days in Dallas
Source:http://www.crh.noaa.gov/lsx/?n=climate_data_wx_record
