A severe winter storm, dubbed Fernan, has significantly disrupted bitcoin mining across the U.S., leading to a sharp decline in network hashrate. As operators reduce electricity consumption to alleviate pressure on the power grid, Foundry USA, the largest mining pool, has seen its computing power plummet by about 60%, from nearly 328 exahashes per second (EH/s) to around 139 EH/s. This drop has contributed to a total network decline of approximately 200 EH/s, pushing average bitcoin block times beyond the usual 10-minute target, now averaging around 12.4 minutes. Other mining pools, like Luxor, have also reported substantial declines in hashrate, further indicating that the effects of the storm and related curtailments may exceed 110 EH/s across various pools. Miners are increasingly acting as flexible loads, participating in demand-response programs that allow them to quickly shut down operations and sell energy back to the grid during peak demand. This trend has been observed in previous weather disruptions, such as in Texas during the 2024 winter storm, where mining hashrate dropped by 25% to relieve grid stress. The current slowdown is mechanical, not structural. As the storm subsides and miners restart their equipment, hashrate is expected to recover, normalizing block times. However, there are concerns about the flexibility of this model. With parts of the mining industry diversifying into artificial intelligence and high-performance computing, the tolerance for sudden shutdowns may decrease, potentially changing how these operations interact with power markets in future crises.