May has gotten weird. After several days of unstable weather, storms, and lower temperatures than usual for this time of year, the weekend arrives marked by a phenomenon traditionally known as the ‘Ice Saints’, a late cold spell that usually occurs in mid-May and has particularly worried the countryside for centuries.
Meteorologist José Antonio Maldonado explained on Meteored that this episode is associated with an influx of cold air that breaks with the spring feeling and leaves an atmosphere more typical of March than mid-May. The situation will be accompanied by rain, storms in some places, and snow in mountainous areas, although the cold will not last too long.
From Monday or Tuesday, temperatures will begin to rise and by mid-next week, temperatures could exceed 30ºC in numerous observatories, with values above 35ºC in southern areas.
What are the ‘Ice Saints’ and why are they being talked about now
The ‘Ice Saints’ are a popular reference in the European agricultural calendar. They are associated with several days in the Christian calendar of saints -Saint Mamertus, Saint Pancras, Saint Servatius, and Saint Boniface, between May 11th and 14th- on which sharp drops in temperature, late frosts, or cold air intrusions were traditionally observed.
It does not mean that it happens the same way every year or that it is an exact rule, but the expression has remained as a way to describe those cold snaps that arrive when spring already seemed settled. This year the fit is clear: low temperatures for the season, unstable weather, storms, and a much cooler thermal sensation than normal.
AEMET had already indicated that the week of May 11th to 17th would probably be colder than usual in a large part of the Peninsula, especially in the western, central, and southern areas, with more abundant rainfall in the first few days and especially in the northern and western peninsular areas.
Tomorrow's weather on Saturday: cold at dawn, rain in the north, and snow in the mountains
Saturday will be one of the key days of the episode. According to Maldonado, temperatures will hit bottom during the early morning and first hours of the day, especially between 5:00 AM and 8:00 AM, when the cold air will be most noticeable.
During the day, the anticyclone will begin to gain ground in the western half, but the north will continue with very cloudy skies. Rain is expected in Galicia, the Cantabrian regions, and the Pyrenees, as well as weaker precipitation in areas of the northern half. Snow could appear above 1,300 meters in the Pyrenees and the Cantabrian Mountains.
In the southern half, the situation will be less cold during the central hours, although cumulus clouds may form in the afternoon. It will not be a fully stable Saturday across the country, but a difference will begin to be noticed between the north, which will be more humid and cool, and the rest, where the weather will tend to clear up somewhat more.
The weather on Sunday: partial improvement, but still cool in several areas
On Sunday, the progressive improvement will continue, although it is not yet possible to speak of widespread heat. The cold air mass will gradually lose strength and temperatures will begin to recover in many areas, especially during the central hours of the day.
The far north will continue to be the area most exposed to cloudiness and possible precipitation, while in a large part of the central and southern peninsular regions the atmosphere will be calmer. Nevertheless, the minimum temperatures may remain low for May, so the contrast between morning and afternoon will be significant.
The practical takeaway is simple: Sunday will be a better day than Saturday for outdoor plans in many areas, but it is still advisable to bring a layer of warm clothing if you go out early or return late.
Madrid: San Isidro with cool weather, possible rain, and improvement during the weekend
In Madrid, today, San Isidro's Friday, has arrived cool, with clouds and the possibility of showers during the afternoon. For Saturday and Sunday, the forecast improves: Saturday is expected to be more pleasant, with sun and clouds, and highs around 21ºC; Sunday could reach up to 22ºC, although with more cloudiness in the afternoon.
The night will remain cool. Minimum temperatures will range between 6ºC and 10ºC during the weekend, so the plan for the meadow, concerts, or a night walk for San Isidro calls for a light jacket. Madrid will not be for dramatic feathers, but neither for a brave t-shirt at ten at night.
For those with San Isidro plans, the recommendation is clear: a small umbrella this Friday, some warm clothing at night, and more leeway to enjoy Saturday and Sunday, when the weather will be much more pleasant.
Where it will rain the most this weekend
The most important rains will be concentrated in the northern third of the peninsula. Maldonado points to persistent precipitation in the Cantabrian regions and in Girona, where they could be heavy and accompanied by storms. There will also be instability in the Balearic Islands and in the vicinity of Cabo de la Nao.
The AEMET also points to locally heavy showers and thunderstorms in Girona and, with less probability, in the Balearic Islands and in the vicinity of Cape Nao.
Therefore, the weekend map is quite well-defined: a rainier and more unstable north, mountain areas with snow at high altitudes, the Mediterranean with a risk of isolated storms, and the center-south with a tendency towards gradual improvement.
The big change will come next week: from late cold to over 30ºC
The most striking part of the episode is the contrast that comes afterward. The cold of the 'Ice Saints' will not stay too long. According to Maldonado, from Monday or Tuesday, temperatures will begin to rise, and by the middle of next week, maximums above 30ºC could be reached in many observatories, and even exceed 35ºC in some southern locations.
That thermal jump explains why May weather can be so disconcerting: in a matter of a few days, one can go from snow at high altitudes and cold mornings to almost summer afternoons in a large part of the country.