MR tankers in the Atlantic finished the week on a high note, but how much higher they can go depends on competing factors on either side of the ocean.

The Baltic Exchange’s Atlantic basin time charter equivalent rate assessment skyrocketed by nearly $20,000 in four days, rising from $36,176 per day on Monday to close the week at $56,016 per day on Friday. The jump represents a 52.3% jump compared to the close of the prior week.

The rally included jumps of $8,828 on Thursday and $8,452 on Friday.

“In the USG there has been a flurry for fixing this week,” the Baltic Exchange said in its weekly note, referring to the US Gulf.

Its analysts said that in combination with other factors including Panama Canal delays, rates on the TC14 route from the US Gulf to Europe rose 78 Worldscale points to WS 247.

According to automatic identification system data, there are at least 35 product tankers in and in the vicinity of the Panama Canal.

The TC14 route from the US Gulf to Europe is one of two legs making up the Atlantic basin MR assessment, along with the front-haul TC2 route from Europe to the US East Coast.

The TC2 rose $1,419 on Friday to reach $34,871 per day on a time charter equivalent basis, with Howe Robinson reporting two fixtures were done at WS 345, higher than the Baltic Exchange’s reading of just under WS 343.

The broker suggested the improved rates might not last, however.

“Owners’ sentiment still firm but with an almost completely empty cargo list in the North and a couple of ships now sitting spot, the momentum could stall, and rates come under pressure unless we see more enquiry,” Howe Robinson said.

Overall, the Baltic Clean Tanker Index fell four points to 1,465, roughly flat during the week after starting at 1,444.

The Pacific basin MR assessment fell $9,676 over the course of the week to hit $33,657 per day on Friday.