The frequency of rain and thunderstorms is expected to increase from this Friday, with winds forecast to reach gale force strength.
Gusts of around 90km/h are being predicted for coastal areas, while people in high-lying areas have been told to prepare for winds that escalate to speeds of up to 110km/h.
In addition to heavy downpours, the Met Office has also warned of extremely unstable conditions along the country’s coastline, with waves of as high as eight metres expected to strike between Saturday and Sunday.
In an alert issued on Thursday, the Portuguese IPMA Met Office said the worst of the weather would be experienced from this Friday and last until Sunday. However, the unstable weather is set to last into next week, with frequent rain showers and heavy downpours remaining a common feature of the current weather pattern.
This comes following the formation of a depression to the west of the Azores islands earlier in the week, which is being forced along at a steady pace in the direction of mainland Portugal by a tropical storm formed further to the west.
IPMA meteorologist Maria João Frada forecast that the worst of the weather could be felt as soon as this Friday.
She also said that hail storms can be expected on mainland Portugal on Saturday morning.
Frada said the actual conditions remain hard to predict with any reliable accuracy and warned that localised and extreme weather phenomenon could develop rapidly depending on prevailing conditions.
Civil Protection vehicles are already on high alert and have been seen patrolling risk areas. They have also called on the civilian population to take additional care with the expected deterioration in weather conditions.
Meteorologists at weather site AccuWeather said while a pair of storms will bring additional rain and gusty winds to the region through Friday, a more powerful storm will arrive at the start of the weekend.
They warned that this storm could bring similar impacts as ‘Storm Emma’ which unleashed powerful winds and a month’s worth of rainfall in parts of Portugal last week.
AccuWeather also predicted that strong winds will be capable of causing downed trees and power outages.
Weather experts added saturated soil from the recent heavy rainfall will increase the risk of falling trees and also heighten the risk for mudslides from any additional rain.