Houston — Portland, Oregon, rack gasoline has jumped more than 33 cents since March 12 on ethanol shortages tied to the recent "bomb cyclone" in the US Midwest that set off flooding and interrupted rail movement of ethanol, according to DTN data Wednesday and market sources.

Rack gasoline in all US markets would be expected to rise during the current transition to summer product, but the Oregon rack fuel price hike has been steeper than those at many other West Coast racks with support from the ethanol logistics trouble.

Shortages in Tucson, Arizona, last week also were blamed on lagging transportation of ethanol, with some Circle K stations in southern Arizona running out of fuel.

Unbranded 87-unleaded at the Portland rack has risen 33.54 cents/gal since March 12 to $2.2231/gal Wednesday morning, DTN data showed.

In contrast, the same gasoline at the Las Vegas rack, a comparable West Coast facility, has risen just 15.33 cents to $2.0380/gal across the same time period, the data showed.

The price at the Portland rack is substantially higher year on year. It was $2.0957/gal on March 26, 2018. With the logistics issues, competition for gasoline that does include ethanol is increasing.

Record-breaking flooding was reported throughout the Midwest earlier this month. Farmers in Corn Belt states have reported crop losses to the tune of 1.34 million bushels of corn that were being held in storage units, the US Grains Council said.

A Nebraska Corn Board representative said flooding had caused an estimated $440 million in damage and there was no clear timeline on when farms might be expected to be resume production.

Flooding in the region has also caused major transportation issues, delaying both the manufacturing of ethanol in the Midwest and its distribution nationwide.

The US West Coast has been dogged by ethanol shortages after parts of the Union Pacific and Burlington Northern Santa Fe railroad networks were blocked by flood waters.

The railroads said portions of the rail lines in Nebraska, Iowa, and Missouri remained impassable as of Tuesday. The outages have kept ethanol shipments bottled up in the US Midwest, where the majority of the country's ethanol plants are located.

In a letter to the US transportation secretary Elaine Chao, Emily Skor, CEO of Growth Energy, a biofuels trade association, said it was imperative the nation's railroads did everything in their power to prioritize ethanol shipments in order to stabilize gasoline prices.

S&P Global Platts on Tuesday assessed Northern California ethanol with a 93.55 carbon intensity value at $1.5150/gal, at a 10.25-cent premium to Chicago Argo ethanol. Prior to the storm, on March 13, Platts assessed the Northern California market at $1.2025/gal, and a 10.25 cents discount to Argo.

When asked about ethanol shortages in the Pacific Northwest, sources said the impact was being felt downstream in the supply chain and that differentials in the region rose rapidly earlier in the week.

Data from the US Energy Information Administration released Wednesday showed West Coast stocks of fuel ethanol fell 13% last week to 2.19 million barrels from 2.52 million barrels.

Gasoline blendstock on the Olympic Pipeline at Portland last traded at the NYMEX April RBOB futures contract plus 18.25 cents/gal, after being assessed Tuesday at 18 cents/gal above front-month futures and up 15.25 cents/gal since March 12.

--Kenneth Raphael, kenneth.raphael@spglobal.com

--Jeffrey Bair, jeffrey.bair@spglobal.com

--Wes Swift, wesley.swift@spglobal.com

--Edited by Keiron Greenhalgh, keiron.greenhalgh@spglobal.com