In continental Portugal, the summer of 2017 (June, July, August) was characterized by values of the average air temperature above normal value and values of the amount of precipitation much lower, being classified as hot and extremely dry.
This was the 6th warmest summer since 2000 (and the 9th hottest since 1931) with a mean temperature of 22.70°C, 1.43°C above the mean value (see Figure).
Since 1931, 6 of the 10 hottest summers occurred after the year 2000, with summer 2005 being the hottest in 87 years.In the summer of 2017 the average value of the maximum air temperature was the 3rd highest value since 1931 (30.22°C), 2.59°C above mean value.
The mean value of minimum air temperature (15.18°C) was 0.31°C higher than normal. Higher minimum temperature values occurred in about 30% of summers.
The summer of 2017 was the third driest since 2000 (after 2005 and 2016) and the 7th driest since 1931. The values of the amount of precipitation that occurred in the months of June to August, about 23 mm, correspond to about 40 % of the mean value (see Figure).
• Exceptionally hot weather in June:
• 3rd warmest month of June since 1931;
• Heat wave in the period from 7 to 24 June with duration of 17/18 days in the interior regions North and Center (9 stations) and 11/12 days in the other regions of the interior;
• Days 17 and 18 were exceeded the previous highs of the daily maximum temperature for the month of June, in almost the whole territory.
• Heat wave from 12 to 17 July: duration of 6/7 days in the interior regions.
• Meteorological drought:
• June: 80% of the territory in severe drought (72.3%) and extreme (7.3%);
• July: 79% of the territory in severe drought (69.6%) and extreme (9.2%);
• August: 60% of the territory in severe drought (58.9%) and extreme (0.7%).