Heatwave and severe thunderstorms of 19th-22nd June 1936

[Weather-history]

There was a short heatwave from the 19th to the 21st of June 1936, when maxima got into the 30s.  31.7°C on the 20th and 21st being the highest record. The heatwave did not last long though as it turned into an increasingly thundery breakdown with heavy thunderstorms breaking out over many western and southern areas.

 

 

South Farnborough: a storm occurred on the 20th of June from 2.05pm to 2.25pm. 30mp squalls reported and the thermometer fell from 85.5F to 70.0F in 28 minutes. A second storm from 9.10pm to 10.20pm with 48mph gusts. Cherry sized hail fell

Hailsham: 2.2" of rain on the 19th

Wigan: 2.11" of rain on the 22nd

The far north of Scotland escaped with Lerwick recording 17.3hrs of sunshine on the 21st.

 

Bit of an odd summer 1936 was.

July was a total washout, the wettest since 1888 and yet August was the driest since 1818 for England and Wales.

Summer CETwise, it was unremarkable with 15.4°C 

 

[A Face like Thunder]

As you say, the summer of 1936 was a bit of an oddity. Philip Eden noted 'thunderstorms, hailstorms and flooding from May to August', including 6th May, 21st and 28th June, and Brazell noted 205% of average rainfall in London in June 1936 although, perhaps surprisingly, the wettest day had only 0.57ins of rain. 

[Roger J Smith]

That summer became incredibly hot in central and eastern North America. Many locations have their highest temperature of record in a spell that began around July 5-6 in the central plains states and spread to the east coast and Great Lakes regions by 8th. Toronto had three consecutive days at 105 F (as they were recording temps in that era) 8th-10th, and NYC had its hottest day on 9th (106 F). Other locations were even hotter, and a location in North Dakota hit 122 F or 50 C, a reading otherwise only seen in the desert southwest region. The severe heat continued to come and go all summer with more records set although more typical values such as a reading of 97 F on August 3rd at Toronto. May and September also had some brief hot spells but June 1936 was fairly cool except in Texas and the southwestern U.S. where the summer heat wave was building up. Nights provided little relief (lows near 80F) and with air conditioning almost unknown, there were thousands of deaths in large cities from heat prostration; people took to sleeping outside during the hottest portion of the July heat wave. Oddly it also hit 100F on 9th and 10th of July 1937 in New York City. 

The hottest temperatures before and after the 1936 heat wave in NYC were 104 (in August 1918 and also in July 1977 and 2011). For Toronto, a similar heat wave in July 1911 hit 103F and Aug 1918 had 102F; the highest reading after 1936 was in August 1948 (102F) and more recently it was 101F in July 2011. 

Both the 1936 and 1937 heat waves extended into the Canadian prairies and set all-time records there including 45 C in Saskatchewan on 5 July 1937 and 44 C in southern Manitoba in July 1936. Those were Canadian records until the "heat dome" event of June 2021 when Lytton BC hit 49C on 30 June (and burned to the ground in a fire later that same day). It was 44 C near my location on that date and felt like a summer heat wave in the desert regions.