The respite from the heat may last very little. From Thursday, August 20, temperatures will rise significantly again in Sardinia, with the possibility of once again reaching values close to 40 degrees in inland areas.

A new influx of very warm air from North Africa will in fact affect the central Mediterranean, just as an Atlantic disturbance brings thunderstorms and a drop in temperatures to the northern regions.

Italy could therefore once again find itself split in two: bad weather in the North, intense heat across the Islands and in the South.

39 degrees already on Tuesday in Cagliari

In reality, the heat will never completely leave Sardinia over the coming days.

For Tuesday, August 18, ARPAS forecasts highs of up to 39°C in Cagliari, 37°C in Quartu Sant'Elena and 36°C in Olbia and Iglesias.

A more bearable situation in the northwest, with 32°C forecast in Sassari and 33°C in Alghero.

On Wednesday the 19th, temperatures will begin rising again, especially in inland areas: 38°C are expected in Ozieri and Cagliari, 37°C in Olbia and Iglesias, while Sassari should stop at around 34°C.

Thursday the 20th: the new peak

The day to watch most closely, however, will be Thursday, August 20.

ARPAS indicates an increase in maximum temperatures, locally even a marked one, accompanied by southerly winds that will encourage warmer air to move toward the island.

The regional forecasts do not yet indicate precise temperatures for Thursday. Other weather centers, however, consider it possible to reach peaks of around 40°C in Sardinia, especially in inland areas.

This does not mean that the entire island will reach this threshold: the highest values will probably be concentrated in the areas most exposed to the influx of warm air.

A “fifth heatwave”, but the definition is not official

Several weather centers have been referring in recent days to the fifth heatwave of summer 2026, following a season already marked by numerous periods of extreme heat.

However, the definition should be interpreted correctly: there is no official meteorological numbering system for heatwaves.

Rather, it serves to identify a new phase of very high temperatures that has already affected part of Western Europe and could now shift its hottest core toward the Mediterranean.

A possible new drop on Friday

The peak could also be relatively brief.

In its current outlook, ARPAS forecasts maximum temperatures falling again on Friday, August 21, although the heat should remain the dominant feature, especially in southern Italy.

The projections beyond Thursday still contain some uncertainty and may change with the next updates.

For Sardinia, therefore, the calendar to keep an eye on is already fairly clear: intense heat on Tuesday and Wednesday, another surge on Thursday and possible peaks around 40 degrees.

After a summer that has already put the island's thermometers to the test several times, the heat does not yet seem ready to bid farewell to Sardinia.