When the Weather Turns Mid-Shift: Rain, Wind and Fog Decisions for Traffic Crews

When weather changes during a traffic control shift, the crew asks two questions: can drivers still see, read and react to the work zone, and is the crew still safe? If the answer to either is no, something changes, from re-weighting signs to pausing work or packing down. Agree triggers at the pre-start so the call is fast.

Weather rarely announces itself. A clear morning turns into a southerly change at lunchtime, or a night shift runs into fog at 3 am. This guide covers the decisions crews make when rain, wind, fog, storms or heat arrive mid-shift, who makes them, a worked example and a decision table. It is general guidance only. Your SWMS, risk assessment, traffic guidance scheme (TGS) and company procedure come first, and a TGS must be prepared by a suitably qualified person.

Plan for weather at the pre-start

The quickest weather decisions are the ones already made. At the pre-start:

• Check the forecast for the full shift, including wind gusts, storm warnings, fog and temperature. Use the Bureau of Meteorology or your usual source.
• Agree triggers. For example, "If gusts start blowing signs over, we re-weight; if they keep falling, we call the office." Triggers should match your SWMS.
• Check gear. Wet-weather gear in high-visibility colours, spare sandbags or weights, torches, spare batteries, sunscreen and water.
• Know the escape plan. Where the crew shelters in a storm, and who calls the client if work stops.
• Agree who decides. Usually the supervisor, in contact with the client, but anyone can call a stop for immediate danger.

Rain: visibility, surfaces and drivers

Rain changes three things at once:

• Visibility. Drivers see less through wet windscreens, and spray from trucks hides signs and controllers. Signs that were readable in sunshine can disappear behind spray.
• Stopping distances. Wet roads lengthen braking distances. The TGS distances were designed for the site, but queues that end near a crest or bend become more dangerous. The stopping sight distance guide explains why.
• Surfaces. Steel plates, painted lines, temporary surfaces and grassy verges get slippery for workers and pedestrians. Excavations can fill and edges can soften.

Responses to consider: increase inspections and drive-throughs, clean sign faces, check end-of-queue warning, rotate controllers so nobody stands soaked and cold too long, and stop activities such as line marking that the rain affects. If rain floods the work area or cuts visibility below what the layout needs, pause.

Wind: signs, barriers and debris

Wind is the most common mid-shift weather problem for traffic crews because it moves equipment.

• Signs fall or twist. A sign lying on the road is both missing and a hazard. A twisted sign faces away from drivers.
• Bats become hard to hold. A controller who can't keep the bat steady can't signal clearly.
• Barriers and fencing move. Fencing panels act like sails; lightweight barriers can shift.
• Debris flies. Branches, loose material from the site and dust reduce visibility and can injure.

Responses: re-weight sign stands as the supplier specifies, recheck every sign after a gust, lower or secure fencing, and consider whether works such as crane lifts or elevated work platforms must stop under their own limits. If devices can't be kept stable, stop and consider packing down. The wind and sign stability guide covers equipment in detail.

Fog, smoke and dust: when drivers can't see you

Fog, bushfire smoke and heavy dust all cut sight distance, and the work zone may now be designed for visibility it no longer has.

• Signs and the end of the queue may not be visible in time.
• Controllers may not be seen until drivers are almost on them.
• Night fog combined with glare from work lights is especially bad.

Responses: increase checks and drive-throughs, check whether the TGS or the approval allows any low-visibility measures, use the lighting and devices it provides for, and pause or stop work if drivers cannot see the site in time. Never solve fog by moving controllers further into the road to be seen.

Storms, lightning and heat

Storms and lightning. Traffic controllers stand in open spaces, often next to metal signs and vehicles. When a storm approaches, follow your company's procedure for lightning, which typically means stopping work, holding or releasing traffic as planned and getting the crew to shelter, often in vehicles. Plan where the crew goes before the storm arrives.

Heat. Hot afternoons build up over the shift. Watch for heat stress: headaches, dizziness, confusion, cramps. Rotate positions, provide shade and water, and relieve early. See heat stress and traffic controllers.

Packing down safely when the weather forces it

Deciding to pack down in bad weather is only half the decision. Pack-down is one of the most exposed tasks in traffic control, and wind, rain or fog make it riskier. A few points help:

• Wait for the worst to pass if the layout is still safe. A closure that is stable and visible may be safer left in place for 30 minutes than removed in a downpour.
• Pack down in the planned order, usually the reverse of set-up, removing devices nearest the work area first and advance warning last, as your TGS and procedure require.
• Keep a vehicle positioned as the procedure requires to protect workers collecting devices, and keep beacons on.
• Don't carry large signs across lanes in strong gusts. A sign face can pull a person off balance into traffic.
• Tell the client and the office before you start, and note the time each stage is cleared.

If the site needs to stay closed after the crew leaves, the after-care arrangements apply, and devices must be secure enough to survive the weather overnight.

Example scenario: southerly change on a lane closure

Here is how this plays out on a typical job. The site is a lane closure on a four-lane road with a posted 70 km/h limit, for kerb and gutter works. The crew is a supervisor and two traffic controllers managing the closure and a site access point. The forecast at the pre-start says hot morning, gusty southerly change mid-afternoon with possible thunderstorms.

1. 6:15 am pre-start. The supervisor briefs the forecast and the triggers: "When the change comes, we re-weight everything and do a full check. If signs keep going over or we see lightning, I'll call the office and the client." Extra sandbags are loaded.
2. 11:00 am. It's hot. Controllers rotate every hour and take water breaks in the shade of the work area. One controller says they feel light-headed and is relieved early.
3. 2:20 pm. The wind swings and strengthens. Two signs on the approach blow over. TC 1 radios: "Two signs down on the northern approach." The supervisor calls the works crew to hold plant at the access point while TC 2 holds trucks.
4. 2:30 pm. The supervisor and TC 2 re-weight and re-stand the signs, then do a drive-through. One sign keeps twisting. It is re-weighted further and checked again ten minutes later.
5. 2:55 pm. Rain starts heavily, with thunder in the distance. Visibility drops and spray hides the taper. The supervisor calls the client's site manager: "We've got lightning approaching and the taper's hard to see. I'm stopping work and the crew is going to the vehicles. Closure stays in place and we'll inspect it once it passes."
6. 3:30 pm. The storm passes. The supervisor inspects the layout on foot and by drive-through. One cone line has shifted; it is corrected. Work resumes at 3:45 pm.
7. Records. The site diary notes the times, the conditions, who was told, the corrections and the 50-minute pause. The office uses it to explain the timesheet to the client.

Weather decision table

This table is an example to adapt to your SWMS, not a rule. Write your own triggers into the SWMS for the site.

Who makes the call and what to record

The supervisor generally makes weather decisions, in contact with the client and the office. That doesn't override anyone's right to stop work: under WHS laws, workers can cease unsafe work where there is a serious risk from an immediate or imminent hazard. Check the detail with SafeWork NSW or Safe Work Australia.

Record:

• the time conditions changed, and what they were
• what you saw (signs down, spray, lightning)
• what you did and when
• who you told: client, office
• when work resumed or the site was packed down
• any equipment damaged

Good weather records also matter commercially. A note that says "work stopped 2:55 pm to 3:45 pm, storm, client's site manager notified" saves an argument when the docket is reviewed. The traffic control site diary guide covers what else to capture.

Next steps

Add a weather line and triggers to tomorrow's pre-start, and check the shift's forecast before you leave the depot. If your crew records pre-starts and timesheets digitally, for example in TrafWise, add weather notes and stoppage times at the time they happen so the docket matches the diary.