Cold weather in US spurred Bitcoin's first negative difficulty adjustment in four months

As a powerful Arctic blast sent temperatures plunging across the southern U.S. in January, the subsequent rise in energy prices meant U.S.-based Bitcoin mining firms struggled to mine profitably. The result: Bitcoin's mining difficulty adjusted downward for the first time since late September, 2024. 

Bitcoin's mining difficulty adjusts every two weeks based on the performance of miners, with a goal of keeping the time between blocks around ten minutes. The mining difficulty decreases when less hash power is available on the network, making it easier for miners to discover new blocks. 

The mining difficulty has remained steady or increased at each two-week interval for the past six months, with two exceptions: the difficulty fell on September 25, 2024, after reaching an all-time high earlier that month, and it fell again on January 27, 2025. 

The recent downward adjustment was spurred by the cold weather that sent temperatures plunging across many parts of the United States, according to Bitcoin mining firm Luxor . The cold weather led to higher demand for natural gas and decreased efficiency from renewable energy sources, increasing the price of electricity and making Bitcoin more challenging to mine profitably for U.S.-based firms. 

Miner revenue per terahash decreased slightly in January compared to December, suggesting that firms had a more difficult time mining Bitcoin for a profit, according to The Block's data. 

According to Luxor's estimates, the U.S. holds a 36% share of the global Bitcoin mining hashrate, with Texas alone contributing around 17%. Several U.S.-based Bitcoin mining firms, such as Riot Platforms , which operates the country's largest mining firm in Rockdale, Texas, have recently announced plans to diversify their operations by directing some processing power towards AI and high-performance computing workloads. 

Luxor's research analysts suspect that Bitcoin's difficulty will continue its typical trajectory as the Arctic blast subsides. "Colder weather in the U.S. is a temporary disruption, and we expect hashrate stability to improve as temperatures normalize," they wrote.