Lorraine Williamson
Spain is heading into an unusually intense spell of late-May heat, with temperatures expected to climb towards 40C in some areas and no quick return to normal conditions in sight.
AEMET has warned that the extreme May heat in Spain will be both intense and persistent. The hottest conditions are expected in inland valleys, including the Guadalquivir, Guadiana and Ebro, where temperatures may approach 40 °C during the second half of the week.
The agency has also pointed to tropical nights in some areas, with minimum temperatures staying above 20 °C. That matters because warm nights make it harder for homes, bodies and cities to cool down after very hot days.
What readers need to know
The heat is expected to affect much of mainland Spain, with the south-west and inland valleys facing the highest values.
Cities such as Córdoba, Sevilla and Badajoz could come close to 40 °C, while Madrid may reach around 35 °C. Barcelona could also exceed 30 °C later this week, according to forecasts cited by AS.
AEMET describes the temperatures as extremely high for the time of year. Its message is clear: Spain is entering conditions more typical of the hottest weeks of summer than the final days of May.
Why this heat feels different
Late-May warmth is not unusual in Spain. However, this episode stands out because of its intensity, spread and persistence.
AS reports that AEMET does not yet see a clear return to normal temperatures. That means the heat may continue for several days rather than easing quickly after one or two hot afternoons.
El País also reports that Spain forms part of a wider western European heat episode, with temperatures running between 5 °C and 10 °C above average in some areas.
The areas most likely to feel the worst of it
The Guadalquivir valley, which includes parts of Andalucia, is one of the main areas to watch.
The Guadiana valley, covering parts of Extremadura and western Spain, is also likely to see very high values. The Ebro valley, which can trap heat across parts of Aragón, Navarra, La Rioja and Catalonia, may also approach extreme levels.
The Balearic Islands are not exempt. Cadena SER reports that parts of Mallorca could reach 35 °C to 36 °C this week, with AEMET in the islands describing the episode as clearly abnormal for late May.
Tropical nights add another risk
Daytime heat often gets most attention, but overnight temperatures can be just as important.
When nights stay above 20 °C, people sleep less well and recover less effectively. This can be especially difficult for older people, babies, people with chronic illness and anyone living in homes without good ventilation or air conditioning.
The effect is stronger in cities, where buildings, roads and pavements store heat during the day and release it slowly overnight.
Heat and fire risk go together
The heat also raises concern over fire risk, especially in dry inland areas and places with scrubland, pine forests or abandoned agricultural land.
Cadena SER reported last week that Spain could approach 40 °C in an atypical May episode, with concern over fire conditions rising as temperatures climb.
Even without strong winds, hot and dry weather can make vegetation more flammable. Barbecues, cigarettes, machinery sparks and vehicles parked over dry grass can all create danger in the wrong conditions.
Health advice for residents and visitors
The practical advice is simple, but important.
Avoid the hottest part of the day where possible, especially between early afternoon and late afternoon. Drink water regularly, even before feeling thirsty. Reduce strenuous outdoor exercise and check on older neighbours, relatives and people living alone.
Children and pets should never be left in parked vehicles, even briefly. A car can become dangerously hot within minutes, even if the windows are slightly open.
What tourists should consider
Visitors may underestimate late-May heat because it falls before Spain’s main summer holiday period.
Anyone sightseeing in cities such as Sevilla, Córdoba, Madrid, Zaragoza or Granada should plan around the heat. Early mornings and evenings are safer for walking tours, castle visits, viewpoints and long city routes.
Travellers should also check accommodation carefully. Air conditioning, shutters, fans, shaded terraces and access to drinking water can make a major difference during persistent heat.
Storms may still appear in some areas
The wider weather picture is not only heat.
AS reports that occasional showers could develop in inland parts of the peninsula over the weekend, in some cases with thunderstorms.
That does not mean the heat is over. In Spain, late-spring storms can arrive while temperatures remain unusually high elsewhere, creating sharp contrasts between regions.
A warning before summer has even begun
This spell comes before meteorological summer officially starts, which makes it more striking for residents and visitors planning the weeks ahead.
Spain has seen increasingly early and intense warm spells in recent years. A single hot episode does not define a whole summer, but it does show why heat planning is becoming part of normal life in Spain.
For now, the message is clear. The hottest areas should prepare for near 40 °C conditions, warm nights and several days of discomfort before temperatures return closer to seasonal norms.
The coming days will test Spain’s heat readiness
The next few days will show how long this late-May heat can hold across Spain.
For residents, tourists, outdoor workers and anyone travelling long distances, it is worth treating the forecast as more than an inconvenience. Heat at this level affects health, transport, energy use, pets, sleep and fire risk.
Checking AEMET updates before making plans is the safest habit. Spain may still be in May, but the weather is already behaving like high summer.