Extreme cold January. On Filomena and other historical invasions
That January is cold does not necessarily have to be news, since, according to climatological data, is the month of the year in which the average temperature is lowest (approximately 5 ºC for the whole of mainland Spain). In the month of January, the cold air inlets of polar origin are not usually missed at their appointment, which favors the formation of frosts, also producing snow in areas exposed to humid air flows. More sporadically (not every year), cold air waves occur, characterized by both their intensity and their duration. It is these exceptional situations that give rise to noteworthy meteorological events.
The meteorologist Inocencio Font Tullot, in his book “Historia del clima de España” (INM, 1988) compiles numerous data and references on the rigors of January. They are particularly abundant during the Little Ice Age (PEH), in which, unlike what happens now (immersed in global warming), episodes of extreme cold dominated over those of heat. As an example, in the late seventeenth century, the winter of 1696-97 was particularly harsh. According to him Cronicón Mayoricense de Mut, In mallorca “… From January 3 to 7, 1697 there was a great general snowfall that forced the snow to be dumped from the roofs. Large icebergs were seen floating in the sea ”.
Already in the eighteenth century, we know from a story –cited by Manuel Rico Sinobas and commented by Font Tullot– that in Valladolid, from January 17 to February 1, 1739, the Pisuerga river remained “So deeply frozen that people came in and wandered as they could through the countryside. They danced, had snacks, threw at the bar … “ Extreme cold also made its appearance repeatedly in the 19th century.
According to a Palencia chronicle, also cited by Font Tullot, in December 1835 and January 1836 the temperature dropped so much that “the eggs froze in their shells (…) And what scared us the most was that on the Three Kings’ Day three priests in the Church of San Antolín [en Palencia] their wine ran cold in their chalice, and even after consecration, not without great embarrassment of the one who said mass. “
Freezing January 1985
Following the chronological journey that we have started, we come to the 20th century. We will stop at one of the most outstanding cold waves of that century, which occurred in January 1985. As is often the case with historic cold waves -How is the case-, have multiple pulses or waves. The one in question had a first outbreak, which began on January 5, which extended the extreme cold to the Peninsula and the Balearic Islands between the 6th and 9th. After a few cold, but not icy, subsequent days, the weather flared up again. 12, with temperatures plummeting mainly in the northeast quadrant of the peninsula and the Balearic Islands, between January 15 and 17.
The map that accompanies these lines shows the situation at dawn on January 15, 1985, with the hard core of air located over the southern half of France, extending southward, encompassing the Eastern Cantabrian Sea (where apart from the intense cold snowfalls occurred at sea level), the Alto Ebro, Aragon, Catalonia, the northern half of the Valencia Community and the northern Balearic Islands. The presence of a northeast flow on the surface (as can be deduced from the isobars) intensified the cold greatly in the north and northeast of Catalonia. (the most exposed area). On days 15 and 16, -21 ºC was measured in Arties, on the 16th, -20 ºC in Viella; identical value to that measured on the 16th and 17th at Pont de Suert and at Camprodon. In Olot, -16 ºC was measured on days 14 and 15 of that freezing month of January 1985.
The records of cold at the step of Filomena
This little review of the cold extremes of January would be incomplete without a mention of the cold wave that, in January 2021, followed the historic snowfall caused by the storm Filomena. On the genesis that gave rise to this extraordinary winter episode, rivers of ink ran, in its day, with a lot of information published about it.
This time we will focus on the extraordinarily low temperatures that were recorded the days after the snowfall in the center and east of the peninsula, beating the absolute minimum temperatures of some observatories. The long-lasting presence of the snow cover very effectively cooled the air above the white blanket, producing very intense radiation frosts., favored by anticyclonic weather.
Temperatures remained at values significantly below the average between January 11 and 20. On the 12th the post-Filomena cold wave reached its peak. In Toledo a minimum of -13.4 ºC was reached, becoming the lowest value ever measured at its centennial observatory, while that of Teruel was -21 ºC (also absolute minimum). The lowest minimum temperature values recorded during the cold wave by AEMET stations were -26.5 ºC in Torremocha del Jiloca (Teruel), -25.4 ºC in Bello, also in Teruel, and -25.2 ºC in Molina de Aragón (Guadalajara); all of them also from January 12 and new absolute minimums of their respective series.