After drenching parts of the Kimberley, Pilbara and Gascoyne over the past week, leading to some flooding, tropical low 12U is expected to bring further heavy rain across the western Gascoyne district today, before crossing the coast near Carnarvon and then heading south along the west coast from Friday.
The low will continue to bring strong winds and heavy rain as it moves south and there is a strong likelihood of welcome rain to aid firefighting operations in Perth during Saturday and Sunday.
Strong winds are already being experienced in coastal areas from Carnarvon to Geraldton, and these winds are likely to extend further south over the coming days, with the most powerful winds expected to stay offshore around the western side of the system.
For Perth, strong easterlies are being felt as the low pushes against a high-pressure system to the south. These currently dry and gusty east to south easterlies are blowing across the Perth fire and will continue on Friday.
Easterly winds are forecast to remain fresh and gusty during the weekend but with cooler and more humid conditions as rain extends southward.
How much rain the low generates is highly dependent on the proximity of the low's centre to the coast.
The closer to the coast the low tracks, then the heavier the rain over land.
The heaviest falls of rain will be experienced ahead of the low as it track southwards.
Current forecasts suggest that much of the west coast can expect significant rain from Friday onwards, with amounts decreasing further inland.
Rain and flood forecast:
Rain is expected to start falling in Perth on Saturday, with 20-40mm possible across the weekend, and as much as up to 100 millimetres in isolated areas over the two-day period.
50-75mm is expected today and again tomorrow across western Gascoyne, with up to 150mm in isolated areas. 30-50mm further inland of the Gascoyne with isolated falls up to 100mm today and up to 75mm tomorrow.
On Saturday 30-60mm are possible across much of the central and lower west coast, with up to 100mm in isolated areas and smaller falls inland including the central wheat belt.
On Sunday 30-60mm is possible with up to 100mm in isolated areas across the Lower West and South West districts.
Smaller falls inland including in the Central Wheatbelt, across to Esperance and extending into the western Goldfields, but not as far as Kalgoorlie.
Flooding from heavy rain in the north west is continuing, with parts of the Great Northern Highway affected and Gibb River Road closed.
