West Yorkshire Police stormed a house in Keighley where they discovered a cannabis farm with a value of £80,000.
Suspicions were aroused when eagle-eyed officers spotted a house near Arctic Street with no snow on the roof, despite the freezing conditions.
Upon further investigation they found a strong smell of cannabis coming from the property.
Their suspicions were confirmed when they entered the property where officers found 322 cannabis plants growing in all four bedrooms and in the cellar. Heated lamps which had been used to grow the plants had caused the ice and snow to melt off the roof.
Posting an image of the cannabis farm, PC Caroline Foster said: "Hmmm, I wonder why there is no snow on your roof? 280+ plants seized from an address in Keighley today, some nearly 6ft tall."
Vicky Watson, 44, who lives next door said she had her suspicions about the occupants of the terraced property when they moved in. She had also noticed how warm the walls of her own home had become recently.
"'Two Eastern European blokes, in their 30s, moved in about 18 months ago," she explained.
'"In the cold weather my house is normally freezing because the insulation is rubbish, but since they moved in next door my bathroom has been absolutely red hot. The wall was warm to touch.
"It was suspicious, you could hear fans whirring but no normal sounds of people living there," she added. "They were two blokes with no kids. We thought they were gay.'
Another neighbour praised the police for their swift actions in seizing the haul.
"Over the last few days the smell has got pretty strong and after the snow kept thawing on their roof, you just knew they were growing cannabis.
"Well done for the police turning out on such a freezing cold day to take those drugs off the streets. Now those cannabis farmers have lost their crop I dread to think how they are going to afford their leccy bill."
No-one was found in the house when police arrived and there have been no injuries. There have been no arrests.
According to Mail Online, work is now underway to confiscate the plants, which will be officially examined and valued.
Anyone who has information about drugs in Keighley is asked to contact the Keighley NPT on 101 or the independent Crimestoppers charity on 0800 555 111.