The month of May was the hottest in the last 89 years, along with 2011, with a heat wave lasting 17 days, one of the longest and with the most territorial extension. .
According to the Climatological Bulletin of the Portuguese Institute of the Sea and the Atmosphere (IPMA), available today on the website, May was an “extremely hot and dry” month and is the warmest since 1931, equaling May 2011.
The IPMA also points out that in the period from 17 to 31 at several stations in the surface observation network, a heat wave occurred, from north to south of the continent’s territory.
This wave started on the 17th, 18th of May and lasted until the end of the month, extending in some stations in the northeast of the country until the first days of June.
According to the IPMA, this heat wave had a maximum duration of 16/17 days and can be considered as one of the longest and with the greatest territorial extension for the month of May.
The Institute also points out that during the month there were very high values of air temperature, which were much higher than normal values, in the second half of May, particularly from the 17th.
“It should also be noted that on the 3rd and 26th to the 29th the average value of the maximum air temperature, and mainland Portugal, was above 30 degrees Celsius”, according to the IPMA.
The average value of the average air temperature (19 degrees Celsius) was much higher than the normal (plus 3.26 degrees).
According to the IPMA, the average values of the maximum temperature of (25.40 degrees) and the minimum (12.60 degrees) were the 2nd highest values since 1931.
The lowest value of the minimum temperature was registered on May 10 in Carrazeda de Ansiães (district of Bragança) with 3.3 degrees Celsius and the highest value of the maximum was recorded on the 28th in Pinhão (Vila Real) with 37.3 degrees Celsius .
With regard to rain, the average value of the quantity, 51.2 mm, corresponds to 72% of the normal value 1971-2000 (71.2 mm).
Precipitation values were higher than normal in some places in the southern region and in particular in Alto Alentejo, Península de Setúbal, Baixo Alentejo and in the eastern Algarve.
On the other hand, in the northern region and especially in altitude zones, precipitation values were much lower than normal.
The Climatological Bulletin, made available by the institute, also includes the drought meteorological index (PDSI), which points to a decrease in the area of intensity of meteorological drought in the southern region at the end of May.
However, in the northern interior the class of weak drought has reappeared.
According to the PDSI, at the end of May 75.2% of mainland Portugal was in normal drought, 17.5% in weak drought, 4.7% in moderate drought and 2.6% in light rain.
The IPMA classifies the drought meteorological index into nine classes, which varies between “extreme rain” and “extreme drought”.