Nullarbor Plain Driving: Weather Risks on Australia's Most Remote Road

The Nullarbor Plain is one of those drives that sounds straightforward until you look at the numbers. Temperatures above 45°C. No shade. No mobile signal. Service stations up to 250 km apart. The longest straight stretch of road in Australia — 146.6 km — that gives drivers nothing to focus on but the heat haze rising from tarmac that has baked to 80°C. Understanding what the weather actually does here is the difference between a memorable road trip and a life-threatening situation.

The Eyre Highway crossing is entirely manageable with the right preparation and the right time of year. The wrong time of year, however, is genuinely dangerous.

Route Overview

The Eyre Highway crosses the Nullarbor Plain for approximately 1,675 km from Ceduna (South Australia) to Norseman (Western Australia). The Nullarbor — from the Latin for "no trees" — is one of the world's largest limestone plains, an ancient seabed now exposed as a flat, arid tableland stretching to the Great Australian Bight along its southern edge.

The road is predominantly sealed and in reasonable condition, but the conditions around it are extreme. Service stations (roadhouses) are 150–250 km apart — the longest gap between guaranteed fuel is the 190 km stretch between Nullarbor Roadhouse and Eucla. Most roadhouses sell food, basic mechanical supplies and water, but hours can vary and breakdowns between them in summer heat constitute a genuine emergency.

There is no mobile phone coverage across most of the plain. The landscape provides no shade whatsoever. The nearest hospital to the midpoint of the crossing is hundreds of kilometres away. Emergency services response times across the Nullarbor are measured in hours, not minutes.

Weather Patterns

Summer (December to February)

This is the most dangerous period to cross the Nullarbor. Air temperatures routinely reach 45–50°C across the plain, with extremes above 50°C recorded during heatwave events. These are not exceptional conditions in summer — they are typical.

The road surface itself heats to 80°C or higher. This has two direct effects on vehicles: tyre pressure increases dramatically as air inside the tyre expands (a tyre inflated to the correct pressure in the morning can be dangerously over-inflated by noon), and tyre compound softens and becomes vulnerable to road debris. Tyre blowouts are the most common mechanical failure on the Nullarbor in summer, and a blowout at highway speed (110 km/h) on a car without a full-size spare is immediately a serious situation.

Vehicles themselves overheat. Air conditioning compressors work continuously at maximum load in 45°C conditions and are prone to failure. A vehicle without functioning air conditioning in peak summer Nullarbor heat is not merely uncomfortable — it is dangerous. Core body temperature can rise to dangerous levels within 30–45 minutes in a stationary vehicle with no shade and 48°C ambient temperature.

Spring and Autumn (March–May, September–November)

The shoulder seasons offer optimal temperatures in the range of 20–30°C — manageable for both vehicles and occupants. These are the most popular crossing windows for good reason.

The hazard to be aware of in these months is dust storms. Spring in particular brings haboobs — massive walls of dust and sand driven by thunderstorm outflows — that roll across the plain. A haboob can reduce visibility to zero within seconds and last for hours. The dust is fine enough to penetrate vehicle seals, clog air filters and damage engines. The correct response is to stop completely, turn lights on, and wait — not to continue driving.

Willy-willies (dust devils) are more minor cousins of haboobs — localised rotating columns of dust up to 10 metres high — common on still, hot days in spring and autumn. They are largely a visual curiosity rather than a serious driving hazard, but they can startle inattentive drivers.

Winter (June to August)

The coolest and most manageable crossing period. Daytime temperatures range from 5–20°C, with night-time temperatures dropping below zero in some years. The Nullarbor receives approximately 250mm of annual rainfall, most of which falls in winter months as frontal systems cross from the Southern Ocean.

Winter rain is generally light and falls in short periods. The road drains well. The main weather hazard in winter is inadequate vehicle preparation for cold — specifically, engine coolant without adequate antifreeze concentration can freeze overnight if temperatures drop below -2°C, which occurs at Nullarbor Plain elevations (roughly 200–300m above sea level) during cold winter outbreaks.

Key Weather Risks for Drivers

Extreme heat causing mechanical failure — Tyre blowouts at highway speed are the most common cause of serious breakdowns. Check tyre pressures in the early morning before the road surface heats, and check them again if you have been stationary for an extended period. Carry a full-size spare tyre, not a space-saver, and the tools to change it independently. In summer heat, a jack and changing a tyre takes 20 minutes of extreme physical exertion.
Dehydration emergency — A breakdown in summer without water is a life-threatening situation that can become fatal within hours. The recommended minimum carry is 10 litres of water per person per day. Coolant and radiator water should be carried separately. Do not rely on roadhouses being open or stocked — carry enough water for 2 days beyond your expected crossing time.
Dust storms reducing visibility to zero — If a dust storm (haboob) approaches, pull well off the road, turn on hazard lights and wait it out. Do not park in the road. Do not try to drive through it — the dust wall can extend 1,000m high and visibility inside is genuinely zero. Vehicles that continue risk rear-end collision from following traffic also driving blind.
Wildlife on the road — Kangaroos, wombats and emus are most active at dawn, dusk and night. A collision with a large red kangaroo (up to 90 kg) at 110 km/h is frequently fatal for occupants of small or medium vehicles and causes severe damage to larger ones. Do not drive after dark on the Nullarbor unless your vehicle is equipped with a full bull bar and driving lights, and even then the risk is significantly elevated. Livestock also wanders onto the road in some sections — cattle and sheep represent an equally serious collision hazard.
No communications in emergency — Triple Zero (000) cannot be reached without mobile signal, and there is no signal across most of the Nullarbor. An EPIRB (Emergency Position Indicating Radio Beacon) or PLB (Personal Locator Beacon) is strongly recommended and can be rented from outdoor gear stores in Adelaide or Perth. Satellite phones provide communication capability throughout the crossing. Do not cross in summer without some form of emergency communication that does not depend on a mobile network.

Best Time to Drive

May to August (Australian winter) is the optimal crossing window. Temperatures are manageable, dust storms are less frequent, and wildlife activity is no lower but at least the cooler weather keeps you alert. Departing early (by 6am) allows you to cover significant distance before midday heat.

Avoid December to February entirely unless your vehicle has been specifically prepared: new tyres (all four), functioning air conditioning, a full mechanical check within the previous 12 months, a full-size spare, and a minimum of 20 litres of emergency water. Even with all of that, summer carries risks that are not present in any other season.

Tips for Drivers

Join the RAA (South Australia) or NRMA/RAC (Western Australia) before departure. Both organisations have emergency assistance coverage on the Nullarbor and can organise towing across the plain, though response times are measured in hours.
File a trip plan with police (Ceduna Police Station or Norseman Police Station), including your vehicle details, expected route and expected arrival date. Check in when you arrive.
Carry fuel for 350 km minimum — this covers the longest guaranteed gap with safety margin. Check that your carry cans meet Australian Standards for fuel storage and are secured properly.
Drive only in daylight. The wildlife collision risk at night is not a minor inconvenience — it is a severe, realistic hazard that has killed people. If you cannot complete the day's planned section before dark, stop at a roadhouse and continue in the morning.
Watch for road trains. Road trains on the Nullarbor can be up to 53 metres long (some configurations reach 200 metres) and require up to 1 km of stopping distance at highway speed. Pass with maximum space — well off the tarmac edge — and never cut back in front of a road train after overtaking.
Route Forecast's elevation profile overlaid with weather data confirms what drivers sometimes overlook: the Nullarbor sits at a consistent 200–300m above sea level, and that modest elevation means winter overnight temperatures can dip below freezing across the entire crossing — visible at a glance against the flat profile. Export the forecast as an image to share with whoever is tracking your progress from home or joining you en route; on a crossing with no mobile signal for hours at a time, agreeing on conditions before you set off is straightforward common sense.

Before you head out, use Route Forecast to check the point-by-point weather forecast for the entire route. Wind, rain and temperature at every kilometre, in real time — overlaid on the full elevation profile so you see exactly where weather changes meet each climb and descent. Export the forecast as an image to share with your group before departure.