Temperatures are forecast to climb above 42°C this week as a powerful heatwave and thick Saharan dust cloud spread across southern and eastern Spain. The State Meteorological Agency (AEMET) has issued warnings for Andalucía, Extremadura, Región de Murcia, Castilla-La Mancha, and the southern part of the Valencian Community, where calima will have the strongest effects. AEMET organizes alerts by autonomous community and hazard, while its observation network records hourly conditions and daily extremes at stations including Sevilla Aeropuerto and Sevilla-Tablada.
Saharan dust began moving into the Iberian Peninsula from the south on Tuesday, July 28, 2026, and is now advancing north. By Wednesday, the haze is expected to cover large areas, reducing visibility and giving the sky a milky or ochre hue. AEMET says the episode is likely to last through at least Sunday, August 2, with a high probability of continued extreme conditions. The warning comes amid rising concern over heat: on July 27, Valentina Raffio of El Correo de Andalucía reported that AEMET had flagged a further temperature increase that could bring the summer’s fourth heatwave.
Heat and Dust Intensify
A subtropical ridge over the peninsula and southerly winds are driving this weather pattern, channeling hot air and mineral particles from North Africa. The result: stifling heat and a persistent veil of dust across Spain’s interior, making outdoor conditions challenging and potentially hazardous.
From Wednesday to Friday, calima will be nearly constant in the hardest-hit regions. Dust concentrations are not expected to set records, but they will be high enough to dull the sky and create a heavy atmosphere, especially during peak afternoon hours. In some southwestern and inland areas, Saharan dust may mix with smoke from ongoing wildfires, thickening the haze and compounding health risks for people working outdoors. A July 26 report by El Correo de Andalucía also described wildfire smoke affecting parts of Spain and worsening air quality.
Calima is monitored through atmospheric-composition forecasts and measurements of particulate matter such as PM10. A report on conditions in the Canary Islands cited forecast daily-average PM10 concentrations of 58 micrograms per cubic metre in Gran Canaria and 52 in Fuerteventura, followed by 63 in Tenerife and 58 in La Gomera. Those island figures show the kind of particulate measurements used to assess dust episodes, but they are not readings for mainland Spain.
Calima Spreads North and East
The dust cloud is forecast to move gradually toward Madrid, Castilla y León, Aragón, Navarra, La Rioja, much of eastern Spain, and the Balearic Islands. In the Valencian Community and the Ebro Valley, skies may stay pale and hazy for much of the week, during the hottest period. The Canary Islands are also expected to see a impressive influx of calima and rising temperatures from Thursday, July 30. The most intense heat will hit the mid-altitude and interior zones of the larger islands, where haze could linger for several days.
Record Temperatures Expected
On Wednesday, maximum temperatures are forecast to reach 39 to 41°C in the basic valleys of the southwest, 37 to 39°C in parts of the northern plateau and La Mancha, and 40 to 42°C in the Ebro Valley and northeastern depressions. Localized peaks above 42°C are possible, particularly over the weekend, when the southern interior may also see highs holding between 40 and 42°C. Nights will remain uncomfortably warm, especially in humid areas, making sleep difficult and increasing risks for vulnerable groups.
Authorities recommend following official advisories closely, particularly for people working outdoors or with health conditions. In some cases, workers may be entitled to special leave during periods of extreme heat under applicable labor guidelines. Calima guidance advises people with respiratory or cardiovascular conditions, older adults, and pregnant women to avoid strenuous outdoor activity when dust levels are poor. Keeping windows and doors closed can also limit exposure. Fine dust can irritate the eyes and respiratory tract.
Storms Could Bring Mud Rain
As the weekend approaches, a trough is expected to increase atmospheric instability, especially in the northeastern corner of the peninsula. Thunderstorms in Catalonia and the Pyrenees may coincide with lingering dust. Rain falling through a dust-laden sky can produce muddy precipitation, leaving visible deposits on surfaces. The phenomenon depends on rain and dust overlapping in both time and place, and forecasts remain subject to change.
AEMET advises the public to follow its special heatwave bulletins for the latest updates and safety recommendations.
Episodes of Saharan dust and extreme heat can pose health risks, reduce air quality, and disrupt daily life. Residents are encouraged to take precautions by staying hydrated and limiting outdoor activity during the hottest hours.
