As Sydney braces for soaring temperatures reaching nearly 40 degrees, some of the city’s trains will be operating at a slower pace to ensure safety is maintained.
The yellow WOLO signs are be deployed at the end of some train platforms across Sydney during extreme heat conditions.
Authorities confirmed that when WOLO signs are deployed, it places speed restrictions on trains as a safety measure – reducing speed limits above 60km/hr by 10km/hr.
Despite the speed restrictions, trains are not expected to be delayed across Sunday and Monday.
The signs will be deployed as temperatures are forecast to reach 32 degrees and 39 degrees in Sydney and Penrith respectively on Sunday.
NSW Transport minister Jo Haylen said the WOLO signs ensures the safety of commuters and staff as well as preventing damage to rail network and infrastructure.
“It’s going to be a warm couple of days in Sydney, and our trains and track will be out there baking in the elements,” Ms Haylen said.
“We’re focused on making our rail network safer and more reliable, and WOLO signs during extreme heat play a role in that.
“Travelling 10km slower than usual might be inconvenient, but it takes pressure off the tracks and means you get to enjoy our train’s airconditioning for just a little bit longer.”
The reason for the signs is to indicate to drivers to go slower because steel tracks have the potential to expand in the heat.
The term WOLO isn’t an acronym but instead it is a remnant from when old telegraph codes were used on the railway to communicate between offices, stations, locomotive depots and goods yards.
WOLO was the telegram code sent out on the railway as a condition forced upon drivers to reduce their train speed in case of track that had buckled or swelled under high temperatures.
This instruction made it easier drivers to stop short of impacted track, or safely pass through weak sections without derailment.
The decision to deploy the WOLO signs comes as the Bureau of Meteorology forecasts extreme heat in some parts of the state.
Sydney’s CBD is forecast to reach 32 degrees on Sunday and then up to 35 degrees on Monday.
Those in Penrith will be sweating even more as the temperature peaks at 39C on Sunday and 38C on Monday.
Melbourne will also see high temperatures with a top of 38 degrees on Sunday before a cooler change comes in on Monday, with 22 degrees forecast for the start of the week.
Brisbane will hit 32 degrees both days, while Adelaide will reach 36 degrees on Sunday but only 25 degrees on Monday.
Perth will see a top of 27 degrees on Sunday while Canberra will reach 35 degrees.