Heat waves trigger Amtrak delays, SEPTA slowdowns

You're not the only one moving slower in a heat wave . Extreme temperatures can cause Amtrak delays and lead to slowdowns on SEPTA .

Why it matters: Climate change impacts transportation and we're feeling the effects with hotter, longer commutes.

The big picture: Prolonged high temperatures can cause outdoor rail tracks to expand and deform.

• That means Amtrak and SEPTA trains can operate at slower speeds when heat spikes and railways are closely monitored for kinks.
• Abnormalities aren't very common, but precautionary measures are taken to keep riders safe.

State of play: Travelers are experiencing longer lag times on Amtrak. As the heat dome formed in June, Amtrak warned riders of delays of up to an hour due to speed restrictions placed on trains.

• Typically, Amtrak trains can travel at a maximum of 150 mph along the Northeast Corridor. But with heat restrictions, they can slow to 100 mph or even 80 mph in extreme temperatures.

Between the lines: Heat can also cause other issues for Amtrak like a strain on power systems or brush fires on the tracks — part of the reason behind delays and cancellations that rocked the railways around New York last month.

The intrigue: Two years ago, Amtrak commissioned its first assessment focused on the impacts of climate change in the Northeast corridor. A national study kicked off this year.

Zoom in: SEPTA can reduce outdoor rail and trolley lines by 5-10 mph during extreme temperature swings, spokesperson Andrew Busch tells Axios.

• Yes, but: During prolonged heat waves like the current one, slowing down lines like Regional Rail, trolleys, and sections of the Market-Frankford Line typically isn't necessary, he said.

Plus: During heat waves, SEPTA crews inspect the tracks for warping and overhead electrical wires for sagging.

• When wires sag, they can get tangled or pulled down in the apparatus on the roof of a train or trolley that connects to them (known as a pantograph), causing delays or knocking a line out of service.

That said, temperatures aren't comfortable while waiting. Unlike its trains, SEPTA's underground stations don't have A/C, only fans.

What they're saying: SEPTA doesn't anticipate any significant service disruptions during the current heat wave, but Busch cautioned riders to check the website for travel updates and delays.

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