Effective as of 4:00 PM Wednesday December 8 2021
View the latest severe weather warnings from BOM at http://www.bom.gov.au/wa/warnings/ .
Explanatory notes:
It was a very hot day today with temperatures having reached 40.0°C at the official Mt Lawley site with the hot air mass over the region with the west coast trough deepening offshore.A weak sea breeze has developed over western suburbs.
The west coast trough is expected to move inland tomorrow bringing cooler but humid conditions once the onshore flow becomes established advecting the marine layer onshore.Maximum temperatures depend on how early the west coast trough moves inland. A later arrival of the onshore flow would lead to another very hot day. It is expected to be very hot inland due to the later arrival of the onshore flow.
The slight possibility of showers in the moist onshore flow on Friday and Saturday with a low pressure system to the south of the state.
Mostly sunny conditions thereafter as subtropical high pressure builds to the south. A weak cold front possibly brushes the southwest of the state on Tuesday or Wednesday bringing cooler conditions and the possibility of showers but still plenty of uncertainty this far out.
Wednesday December 8:
City:
22-40 Degrees Celsius
Very hot and mostly sunny.
Chance of any rain:20%
Amount:Nil
Perth Metropolitan Area:
Very hot and mostly sunny.A slight(20%) chance of showers and/or thunderstorms most likely in the early hours and morning.Winds east-northeasterly at 25-40 km/h becoming northeasterly in the morning, easing to 10-20 km/h in the afternoon, increasing to east-northeasterly at 20-30 km/h later at night.Gusts in excess of 80 km/h possible over the hills and foothills early.
Thursday December 9:
City:
24-36 Degrees Celsius
Partly cloudy.
Chance of any rain:5%
Amount:Nil
Perth Metropolitan Area:
Partly cloudy.Very hot inland.Winds northeasterly at 20-30 km/h shifting westerly at 15-25 km/h by afternoon, becoming southwesterly at 5 –15 km/h at night.
Friday December 10:
City:
18-25 Degrees Celsius
Partly cloudy.
Chance of any rain:20%
Amount:Nil
Perth Metropolitan Area:
Partly cloudy.A slight(20%) chance of a shower.Winds west-southwesterly at 10-20 km/h increasing to southwesterly at 20-30 km/h in the morning.
Saturday December 11:
City:
17-25 Degrees Celsius
Possible shower.
Chance of any rain:30%
Amount:0 to 0.4 mm
Perth Metropolitan Area:
Partly cloudy.A slight(30%) chance of a shower.Winds southwesterly at 15-25 km/h becoming south-southwesterly from evening.
Sunday December 12:
City: