Effective as of 4:00 PM Tuesday May 4 2021
Explanatory notes:
Upper level divergence and elevated instability ahead of the upper level disturbance coupled with the deepening trough off the west coast with moist low level air brought rain, showers and thunderstorms today.
The trough offshore acts as a focus for thunderstorm activity, however some rain, showers and also possible thunderstorms over the metropolitan area ahead of the upper level disturbance.
Thunderstorm probability increases overnight as the trough moves inland. Once the upper level disturbance and surface trough move to the east, thunderstorm chances diminish but showers are still expected in the moist onshore flow.
During Thursday, another upper level trough and associated upper level cold pool approaches from the west bringing showers and possible thunderstorms, most likely in the late morning and early afternoon.
Ridge of high pressure builds to the south thereafter leading to fine conditions.
The rest of Tuesday May 4:
Chance of any rain:80%
Perth Metropolitan Area:
Cloudy.A high (80%) chance of showers.The chance of a thunderstorm.Winds north-northeasterly at 15-25 km/h.
Showers.Possible early thunderstorm.
Chance of any rain:100%
Amount:10 to 20 mm
Perth Metropolitan Area:
Partly to mostly cloudy.A very high (100%) chance of showers with the chance of a thunderstorm early easing to a high (80%) chance of showers from morning.Heavy falls possible with thunderstorms early.Winds north-northeasterly at 10-20 km/h becoming northwesterly by morning shifting west-northwesterly at 15-25 km/h by late morning becoming light later at night.
Showers.
Chance of any rain:100%
Amount:5 to 15 mm
Perth Metropolitan Area:
Partly to mostly cloudy.A very high (100%) chance of showers.The chance of a thunderstorm in the late morning and early afternoon.Winds north-northwesterly at 5-15 km/h becoming southwesterly in the afternoon, becoming light.
Partly cloudy.
Chance of any rain:20%
Amount:Nil
Perth Metropolitan Area:
Partly cloudy. Slight(20%) chance of a shower early most likely near the coast.Light winds becoming southeasterly at 10-20 km/h in the morning tending south-southwesterly at 15-25 km/h in the afternoon.