Lumen Sites for mine & construction sites

Pilbara weather for site work

The Pilbara is the heart of Australia’s iron ore industry, from the mines around Newman, Tom Price and Paraburdoo to the ports at Port Hedland and Dampier. It is one of the hottest places in the country, its coast is the most cyclone-prone in Australia, and most of its rain arrives in a few summer months, often all at once.

The year at a glance

Inland towns are the hottest: Paraburdoo and Marble Bar average 41° in January, and Marble Bar averages 97 days a year reaching 40°. The coast is a few degrees cooler but far more humid. Winter is warm by day, with July nights of 14–15° on the coast and cooler inland, down to 7° in Newman. Annual rain is about 270–450 mm, and 55–79% of it falls from December to March. Spring is the driest time: September to November average under 20 mm a month inland, and close to nothing on the coast.

Averages for 1995–2024 from SILO (Queensland Government, CC BY 4.0), interpolated from Bureau of Meteorology observations. Heat-stress days: estimated WBGT reaching 28°, the caution level Lumen Sites starts with. Select a town for its month-by-month figures.
Town	January high	July low	Rain a year (mm)	Wettest month	Days reaching 40°	Heat-stress days
Port Hedland	36°	14°	329	Feb 76 mm	29	229
Karratha	36°	14°	311	Feb 86 mm	22	221
Newman	39°	7°	363	Jan 87 mm	52	157
Tom Price	38°	9°	431	Feb 102 mm	30	141
Paraburdoo	41°	10°	313	Feb 80 mm	75	179
Marble Bar	41°	12°	452	Jan 109 mm	97	220
Onslow	36°	14°	270	Feb 57 mm	19	210
Pannawonica	39°	12°	414	Feb 124 mm	47	207
Roebourne	38°	14°	329	Feb 77 mm	54	234
Wickham	38°	14°	328	Feb 75 mm	39	232
Dampier	35°	15°	304	Feb 83 mm	12	218
Nullagine	40°	10°	414	Feb 102 mm	75	191

Heat and heat stress

Heat-stress days by month

Average heat-stress days a month, 1995–2024: days when the estimated wet bulb globe temperature (WBGT) at the day’s peak reaches 28°, the caution level Lumen Sites starts with. From SILO (Queensland Government, CC BY 4.0), interpolated from Bureau of Meteorology observations.
Town	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Port Hedland	31	28	30	25	10	4	2	4	12	25	28	31
Karratha	31	28	31	26	11	3	1	3	9	22	26	31
Newman	30	27	25	11	1	<1	0	0	1	12	22	29
Tom Price	30	27	25	9	<1	<1	0	0	<1	6	16	28
Paraburdoo	31	28	29	17	2	<1	<1	<1	2	15	24	30
Marble Bar	31	28	30	23	7	2	1	2	11	26	29	31
Onslow	31	28	31	27	12	3	1	2	6	17	23	30
Pannawonica	31	28	30	25	9	2	1	1	6	19	25	31
Roebourne	31	28	31	26	11	3	2	5	12	25	28	31
Wickham	31	28	31	26	11	3	2	4	12	25	28	31
Dampier	31	28	31	26	11	3	1	3	8	21	25	31
Nullagine	31	28	29	17	3	<1	0	<1	5	21	27	31

Inland, the heat is extreme but dry. Newman averages 147 days a year reaching 35° and 52 reaching 40°, with 157 heat-stress days. Marble Bar, famous for a run of 160 consecutive days of 37.8° (100°F) or more in 1923–24, still averages 202 days a year reaching 35°.

On the coast, humidity makes heat stress the bigger problem. Port Hedland reaches 40° on fewer days, 29 a year, but averages 229 heat-stress days, 142 of them at the stop level, with the caution level reached on most days from October and nearly every day from November to March. These figures use the Bureau of Meteorology’s simplified formula, which assumes moderate sun and light wind, so read them as how often heat needs managing. Fly-in fly-out crews arriving from Perth, where January averages 31°, step into 36–41°, so the first days of a summer swing need extra care. The WBGT calculator and heat stress forecasts cover the details.

Cyclones

The coast between Broome and Exmouth is the most cyclone-prone in Australia, according to the Bureau of Meteorology. Cyclones bring destructive winds and storm surge to the coast and shut the ports at Port Hedland and Dampier, and as they move inland they can drop a season’s rain in a few days, flooding pits and cutting roads and rail. See cyclone season for remote sites for the warnings and a preparation timeline.

Rain and floods

February is the wettest month in most towns, with about 55–125 mm on average, mostly from cyclones, monsoon lows and thunderstorms. The averages hide big swings: one cyclone can bring more rain than an average year, and a dry summer can bring almost none. Rivers that are dry for most of the year, such as the Fortescue and the De Grey, can flood and close highways for days. On the coast there is a second, smaller peak in May and June, when northwest cloudbands bring rain. More in rain, the wet season and haul roads.

Storms and lightning

Summer thunderstorms bring lightning stand-downs, especially inland, along with squally winds that can raise dust ahead of the rain. Plant noise makes distant thunder easy to miss, which is why sites rely on detection: see lightning stand-down alerts.

Planning a year on site

Put shutdowns, major lifts and earthworks into June to September, when heat stress is lowest and rain is rare.
Have the cyclone plan, supplies and evacuation arrangements ready by November.
Plan for heat stress from October to April, and most of all from November to March.
Inland, clear winter nights set up temperature inversions, so time blasts for after they break: see blasting and temperature inversions.