December was very rainy and the hottest in the last 92 years in Portugal
During the last month of December, Portugal continental was predominantly on an action of masses of hot, humid and inexplicablysometimes with high content in precipitable water, in a predominant southwest or west flow.
Temperature
According to Portuguese Institute of the Sea and Atmosphere, IPMAin mainland Portugal, in the month of December 2022, the average value of the average air temperature, 12.72 °C, was 2.76 °C above the normal value, being the highest since 1931.
THE average value of maximum air temperature, 17.61 °C, was higher than the normal value with an anomaly of + 1.99 °C, making it the 2nd highest since 1931. The highest value occurred in 2015 and was 16.21 °C.
The average value of the minimum air temperature, 9.58 °C, was much higher than the normal value with an anomaly of +3.53 °C, being the 2nd highest value since 1931after 9.99 °C, which was recorded in 1989.
Deviations from the minimum air temperature, above 3.5 °C in much of the territoryeven having registered deviations greater than 5.0 °C in some stations in the periods from 12 to 14 and 19 to 25 and 29 and 30 minimum. The air temperature was almost always above the normal value, except for the first 4 days of the month.
The lowest value of the minimum air temperature was -4.8 °C, registered in Moor sludge on the 4th and highest value of the maximum temperature, 25.5 °C, occurred in aljezurday 27.
Precipitation
Also according to the IPMA, the average value of the amount of precipitation, 250.4 mm, correspond to a 174% of the normal value, being the 2nd highest value since 2000following 311.5 mm in 2000.
During the month occurred episodes of heavy rainin particular on the 4th and 5th, 7th and 8th, 12th and 13th and in the last days of the month, with the occurrence of floods and floods in various parts of the territory, especially in the region of Greater LisbonTagus valley and algarve.
In some meteorological stations the total monthly precipitation corresponded to the highest value for the month of december.
No diameter 13 were exceeded the daily extremes of rain (09:00 to 09:00 UTC) for December, in 13 seasons, having been even exceeded the absolute extreme in 4 seasons: Lisbon/IG (120.3 mm), barrier (83.4 mm), almada (81.9 mm), lives (98.8 mm).
Drought Monitoring – PDSI Index
AN the percentage of water in the soil increased significantly in almost all the territoryexcept in some places in Baixo Alentejo and Algarve and occasionally in Alto Alentejo.
According to Drought Meteorological Index, PDSIDrought meteorological index calculated by the IPMA for monitoring the drought situation, at the end of December there was again a decrease in the situation of meteorological droughtthat ended up in virtually the entire territory; only a few places in the interior South region are still in mild drought (the least severe drought class of the PDSI Index).
The percentage distribution by classes of the PDSI index in the territory is as follows: 2.9% extreme rain, 28.5% severe rain, 33.3% moderate rain, 10.3% light rain, 18.5% normal, 6.5% light drought.