May started out cold, with rain, snow and hail in Portugal. Despite the rise in temperatures today (2), the weather will continue to be humid and unstable in the coming days due to several fronts that, fed by an atmospheric river, will bring abundant rain to these regions.
In this Thursday (2) was checking a gradual withdrawal of cold air to northern latitudes, which allowed a slight thermal recovery that was reflected in the small increase in maximum temperatures in the North and Center Regions of Continental Portugal.
In these same regions, for much of the day, there was a clear alternation between periods of rain or showers and open and, above 1200 meters of altitude, snow fell. The wind blew mainly from the West quadrant.
Portuguese dams with levels above average in April, but Algarve still on alert
In the Archipelagos of Azores and from Wood the meteorological panorama was also characterized by some instability. In the first group of islands mentioned, it was witnessed rainy periods and overcast or partially cloudy skies and strong wind from the south quadrant. In the second set of islands, the state of the weather manifested itself through scattered cloudinesssometimes with the occurrence of light rain.
Atmospheric river will reach these areas of the Continent on Friday, May 3
As mentioned in the our latest predictions, tomorrow – Friday, May 3 – an Atlantic front, fed by a atmospheric river (loaded with subtropical humidity) will produce rain in areas north of the Mondego river.
It will be especially persistent in Minho (districts of Viana do Castelo and Braga). It will be equally likely in other areas of the North and Center (for example, districts of Harbor It is Real Village), but very less frequent and abundant.
They are also to be expected mild, short and punctual periods of rain in places of Northeast Trás-os-Montes (district of Bragança) and in mountainous areas of districts of Aveiro, Viseu, Coimbra and Guarda.
For the remaining regions, all located south of the aforementioned watercourse (Mondego), the sky will remain practically clear throughout most of the morningwith cloudiness increasing throughout the afternoon from west to east.
The North Region will remain relatively coolbut in many areas of the Center and South the maximum temperatures will already be around the 20/21 ºC (Coimbra, Santarém and Faro, for example) result of the removal of cold air and the arrival of temperate and humid subtropical air.
In these next few days the winds – associated with the channeling of the atmospheric river loaded with subtropical humidity – moderate to strong blows from the South and West quadrants in mainland Portugal and the Azores. In Madeira they will assume variable directions (east, south/southeast and northwest).
Weekend with significant precipitation in these regions and rising temperatures
For Saturday (4) very cloudy or overcast skies are expected, with persistent and occasionally heavy rain in Minho and Douro Litoral. In regions located north of the Montejunto-Estrela mountain system and west of the Condensation Barrier periods of rain or showers will be abundant thanks to the presence of the atmospheric river. To the south of the Tagus River, skies with scattered clouds or partly cloudy are expected.
Temperatures will continue to rise, reaching 24/25 ºC in vast areas of Central Alentejo (Évora), Baixo Alentejo (Beja) and Algarve (Faro). In the Algarve region, some places will even be able to see the thermometer climb to the 27ºC! The wind will blow weak to moderate from the Southwest, occasionally intense in the highlands and coastal strip north of Cape Mondego. In the South Region it will blow weak to moderate from the West quadrant.
A Condensation Barrier It is the mountainous complex responsible for retaining, through the orographic effect, a large part of the cloudiness and precipitation that reaches mainland Portugal “pushed” by the humid winds from the West/Southwest and maritime influence (Atlantic). The Condensation Barrier covers the districts of Viana do Castelo, Braga, Porto, Aveiro and the western areas of the districts of Vila Real and Viseu.
At the Sunday (5) Precipitation is expected from north to south of mainland Portugal. There will be periods of rain, more frequent and likely in the North and Center Regions (in particular in Minho and Douro Litoral). It will be persistent and occasionally intense in the North until mid-afternoon. At South region will be smoother and more dispersed, becoming intermittent during the period of afternoon by progressively moving to rainfall regime.
Massive storm of snow and hail hits Portugal at the beginning of May: see the images
There will be few fluctuations from a thermal point of view. The only most noticeable change will have to do with the prediction of rise in minimum temperatures in the Center and South Regions. The wind will blow from the West quadrant in the South Region, and from the South-Southwest in the remaining regions, generally weak to moderate, sometimes strong in the highlands.
