Unusual snowfall on Portugal mainland: 26-27 February 2016
2016-03-03 (IPMA)
Between 24 and 26 February 2016 a strong westerly flow affected Portugal mainland, with the passage of frontal systems producing precipitation, especially to the north of Montejunto-Estrela mountain system. Snowfall affected regions higher than 600 meters on February 26. On February 27, in post-frontal cold air, a strong northwest flow originated snowfall in even lower quotas and unusual places.
Figure 1 identifies snow on the ground, in cyan, on the mountains of Peneda, Gerês, Larouco, Alvão, Marão, Montemuro, Freita, Caramulo, Estrela and Lousã. The top image was obtained on February 29, two days after the event, when the absence of clouds allowed a wide observation of the surface. The bottom image was obtained on March 1, with a notable reduction of the area covered with snow in the regions where snow is unusual.
In IPMA´s weather station of Penhas Douradas, at an altitude of 1380 meters, a layer of 15 cm of snow depth was measured on the ground on February 27. On February 29, there was still 12 cm of snow depth and on March 2, there was 5 cm of snow depth. The progressive reduction of the area covered with snow in the Estrela mountain is also identifiable in Figure 2, with images obtained at 10am local time on February 29 and March 1, 2 and 3.
The reports presented by media and on the voluntary cooperation platform of IPMA, METOGLOBAL, and on weather forums in the internet suggest that snowfall has occurred in altitudes down to 300 meters, following IPMA´s forecasts in previous days, in particular in mountains as Monchique, Aire, Candeeiros and Montejunto, or in places like Fátima, Leiria, Sobral de Montagraço and Arraiolos.
Figure 1 - Combined images, at 10am local time, from a Meteosat Second Generation satellite, using a near infrared band (1.6 micron) and a high resolution visible band. Snow on the ground in cyan shades. On top - February 29, 2016 ; below - March 1, 2016 .
Figure 2 - Combined images, at 10am local time, from a Meteosat Second Generation satellite, using a near infrared band (1.6 micron) and a high resolution visible band. Snow on the ground in cyan shades. In sequence from left to right, and top to bottom - February 29 , 1, 2 and 3 March 2016 .
