In the village of Busturenga, where the smoke was so thick it was hard in places to see more than a few dozen metres, anxious residents sought on Monday to rescue pets and belongings from homes perilously close to the blaze.
Some attempted to stop the encroaching flames but their small buckets of water did little to stem the advance.
"I've never seen anything like it. The fire was all round the village and the water bombers couldn't get to it because of the smoke," 67-year-old Maria Fatima told AFP.
Wildfires burned all night from Monday to Tuesday across the region, destroying scores of homes and thousands of hectares of woodland and crops.
The flames have killed seven since Saturday, when the authorities placed Portugal on alert because of high temperatures and strong winds.
"We're really scared!" said Maria Ribeiro, 82, tearfully, watching helplessly.
"All my land is burnt... I'm lucky my house wasn't," she added, adjusting the anti-smoke mask covering her mouth and wiping her tears.
"We were really frightened because we've really been left to our own devices. No-one's come to help us."
As she was speaking, a string of fire engines sped past towards the huge flames sweeping through the plantations of resinous eucalyptus surrounding the village.
Portuguese TV showed footage of locals watching nervously as flames licked up a wooden post towards the electricity cables and a garage full of petrol-filled motorbikes.
Helpless
The air on the village square outside the little white church reeked of burning and the dust made it hard to breathe.
Close to Ribeiro's house, residents armed with hoes and buckets sloshed water over the gardens and low walls in front of their homes in an effort to protect them.
Maria do Carmo Carvalho, a 70-year-old farmer, hovered outside her house, looking out for the rescue services and fretting about her crops.
"I've never seen anything like it. The worst thing is the wind," she said, her eyes reddened by smoke after battling flames all Monday afternoon to save her hens.
The mountain road into the village was a skein of blackened trees and scorched bushes under a black sky.
"We can't do anything. We'll just have to sit it out," shrugged Antonio Tavares resignedly from his car, which he had pulled up onto the side of the road.
"I'm waiting for the firefighters to let me through," explained the retired carpenter, worried about his workshop on the hillside, which was full of wood.
A 28-year-old Brazilian forestry worker had burned to death nearby on Monday.
He had become trapped by the flames as he tried to retrieve tools from a burning area, the Lusa agency quoted police as saying.
Spanish water bomber planes arrived in Portugal on Monday after the government officially requested help from its European Union partners.
As night fell, villagers could only hope the backup promised this week by France, Greece and Italy arrived in time.