The temperature on May 20, 1911 was between 8.8 °C and 15.8 °C and averaged 11.3 °C. There was 4.2 hours of sunshine (26%). The average windspeed was 3 Bft (moderate breeze) and was prevailing from the north. Source: KNMI
April 8 » Dutch physicist Heike Kamerlingh Onnes discovers superconductivity.
April 27 » Following the resignation and death of William P. Frye, a compromise is reached to rotate the office of President pro tempore of the United States Senate.
July 1 » Germany despatches the gunship SMSPanther to Morocco, sparking the Agadir Crisis.
July 4 » A massive heat wave strikes the northeastern United States, killing 380 people in eleven days and breaking temperature records in several cities.
September 20 » The White Star Line's RMSOlympic collides with the British warship HMSHawke.
November 17 » Omega Psi Phi fraternity was founded on the campus of Howard University in Washington, D.C.
Day of marriage December 20, 1941
The temperature on December 20, 1941 was between 0.2 °C and 6.4 °C and averaged 4.1 °C. There was 0.7 hours of sunshine (9%). The average windspeed was 3 Bft (moderate breeze) and was prevailing from the north. Source: KNMI
In The Netherlands , there was from September 3, 1940 to July 27, 1941 the cabinet Gerbrandy I, with Prof. dr. P.S. Gerbrandy (ARP) as prime minister.
In The Netherlands , there was from July 27, 1941 to February 23, 1945 the cabinet Gerbrandy II, with Prof. dr. P.S. Gerbrandy (ARP) as prime minister.
March 29 » The North American Regional Broadcasting Agreement goes into effect at 03:00 local time.
April 13 » A pact of neutrality between the USSR and Japan is signed.
July 4 » World War II: The Burning of the Riga synagogues: The Great Choral Synagogue in German occupied Riga is burnt with 300 Jews locked in the basement.
August 14 » World War II: Winston Churchill and Franklin D. Roosevelt sign the Atlantic Charter of war stating postwar aims.
September 17 » World War II: A decree of the Soviet State Committee of Defense restores compulsory military training.
October 20 » World War II: Thousands of civilians in German-occupied Serbia are murdered in the Kragujevac massacre.
When copying data from this family tree, please include a reference to the origin: J. van Broekhoven, "Database Van Broekhoven", database, Genealogy Online (https://www.genealogieonline.nl/database-van-broekhoven/I53323.php : accessed February 18, 2026), "Josefus Arnoldus Antonius van Helvert (1911-)".
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