For sure it was an exceptional event. Nevertheless take note of the weather disasters all over the Iberian Peninsula in January 1940, giving you the reference as follows:
“Mediterranean - Strange weather - winter 1939/40” (https://www.2030climate.com/a2005/02_52-Dateien/02_52.html ) excerpts:
1 January 1940; The Atlantic island Madeira reports heavy thunderstorm with heavy flooding. (Neue Zürcher Zeitung, 2 January 1940).
4 January 1940; Heavy rains during several days in Southern Spain caused severe flooding. Water in Guadalquivir River has risen by 15 metres. (Neue Zürcher Zeitung, 5 January 1940).
6 January 1940; Heavy flooding in Tajo river in Portugal. (Neue Zürcher Zeitung, 8 January 1940).
11 January 1940; In Northeast and Central Italy heavy storms with a wind speed up to 120 km from the West was reported, (Neue Zürcher Zeitung, 11 January 1940).
11 January 1940; Macedonia. Several people froze to death in Macedonia. (NYT, 12 January 1940).
11 January 1940; Greece. Storms lashed the Greek coast, driving the passenger vessel Leon ashore. (NYT, 12 January 1940).
13 January 1940; Rome. Reports of death, injury and extensive damage to property came from all over Italy today as a result of one of the worst storms in years, which in Rome disrupted telephone service. Thirteen persons were known to have been killed and three ships wrecked. (NYT, 14 January 1940).
13 January 1940; Temperatures fell in Portugal; Sierre de Estella reports 9°C below zero temperatures; and very unusual snowfall at Coimbra. (Neue Zürcher Zeitung, 14 January 1940).
14 January 1940; Snowstorms continued all over Spain preventing ships from leaving ports. The speed train from Valencia to Tarragona stranded in snow. (Neue Zürcher Zeitung, 14 January 1940).
15 January 1940; Heavy snowstorms all over Spain continue. (Neue Zürcher Zeitung, 15 January 1940).
18 January 1940; In the Navarro region a violent snowstorm rages; the road from Irun to Madrid is covered with 70 cm snow (Neue Zürcher Zeitung, 18 January 1940).
21 January 1940; In Paris (Porte de Lilas) minus 20 degrees Celsius; it is the severest winter since 1917 with 22 degrees below zero. (Neue Zürcher Zeitung, 22 January 1940).
23 January 1940; At Madrid it has been snowing continuously for the last few days. Snow cover was higher than in the winter of 1906. Never before has so much snow been recorded. At Bilbao the traffic was interrupted and work at the seaport stopped. (Neue Zürcher Zeitung, 25 January 1940).
25 January 1940; All over a number of Spanish provinces cold has doubled. In Madrid the temperature fell to -18°C; at Valladolid to -13°C. (Neue Zürcher Zeitung, 26 January 1940).
