Midwest refinery utilization fell to 85.6% of operable capacity in the week ending September 25, during the fall maintenance season, according to weekly refinery data from the Energy Information Administration.

Nationally, refineries ran at 92.5% utilization that week, processing 16.257 million barrels per day of crude oil against operable capacity of 18.027 million barrels per day. Runs then recovered gradually through October. By the week ending October 30, national utilization had climbed to 94.5%, with crude inputs of 16.725 million barrels per day and operable capacity of 18.044 million barrels per day, according to the agency's release dated November 4.

The East Coast saw the deepest dip. Refineries in that region, which have 928,000 barrels per day of operable capacity, ran at 77.9% in the week ending October 2 before rising to 89.5% by October 30. Midwest plants, with 4.283 million barrels per day of capacity, recovered to 92.9% over the same stretch, after holding between 88.1% and 90.2% for most of October.

Gulf Coast refiners, which account for 9.903 million barrels per day of operable capacity, the largest regional share, stayed between 94.9% and 96.3% throughout the six-week period. The West Coast moved in the opposite direction late in the month, with utilization falling from 95.1% in the week ending October 23 to 91.7% a week later, when crude inputs in that region totaled 1.963 million barrels per day. Rocky Mountain refineries reported utilization as high as 100.6% in mid-October.

The accompanying EIA chart tracks weekly U.S. refinery utilization since 1990. The agency's next weekly update is scheduled for November 12.

Source: U.S. Energy Information Administration -- https://www.eia.gov/dnav/pet/pet_pnp_wiup_dcu_nus_w.htm