7 day weather forecast

Effective as of 4:00 PM Monday July 27

Explanatory notes:


As at 4 PM, the cold front lied slightly north of Mandurah and is expected to move over the Perth region in the next 2 hours. Behind the cold front also lies a rain band.

On Tuesday, plenty of stratocumulus clouds with moist southwesterly flow, slight chance of light showers, whether or not showers occur depends on the height of the temperature inversion.ECMWF model currently has the height of the temperature inversion at around 1600 meters.

Stratocumulus-dry conditions on Wednesday with a high pressure ridge over the region.

Early on Wednesday whether or not fog occurs depends on cloud cover, moist air leads to the possibility of fog, however, there is expected to be some cloud cover blown in from offshore.

Cold morning on Thursday with light winds and clear skies, I downgraded the minimum temperature forecast to lie lower than the OCF guidance.

On Friday, the passage of a decaying cold front brings the possibility of showers.


Plenty of uncertainty on conditions towards the end of the forecast period with a large spread in solutions between models and model ensembles.

The rest of Monday July 27:

City:

Rain,showers.

Chance of any rain:90%

Perth Metropolitan Area:

Mostly cloudy. A very high(90%) chance of rain,showers.Winds northwestely at 20-30 km/h shifting wet-southwesterly at 15-25 km/h.

Tuesday July 28:

City:

11-20 Degrees Celsius

Possible light  shower.

Chance of any rain:30%

Amount:0 to 0.2 mm

Perth Metropolitan Area:

Partly to mostly cloudy.A slight(30%) chance of light showers.Light winds tending west-southwesterly at 10-20 km/h during the day.

Wednesday July 29:

City:

9-20 Degrees Celsius

Partly cloudy.

Chance of any rain:10%

Amount:Nil

Perth Metropolitan Area:

Partly cloudy.Light winds.

Thursday July 30:

City:

6-21 Degrees Celsius

PM clouds.

Chance of any rain:5%

Amount:Nil

Perth Metropolitan Area:

A sunny morning becoming partly cloudy from afternoon.Light winds becoming southwesterly at 10-20 km/h from afternoon.

Friday July 31:

City:

10-20 Degrees Celsius

Shower or two.

Chance of any rain:50%

Amount:0 to 1 mm

Perth Metropolitan Area:

Partly cloudy.A medium(50%) chance of showers. Light winds tending south-southwesterly at 15-25 km/h during the day.

Saturday August 1:

City:

8-19 Degrees Celsius

Partly cloudy.

Chance of any rain:10%

Amount:Nil

Perth Metropolitan Area:

Partly cloudy.Winds southeasterly at 10-20 km/h.

Sunday August 1:

City:

8-19 Degrees Celsius

Mostly sunny.

Chance of any rain:5%

Amount:Nil

Perth Metropolitan Area:

Mostly sunny.Winds southeasterly at 10-20 km/h.

Monday August 2:

City:

8-18 Degrees Celsius

Mostly sunny.

Chance of any rain:5%

Amount:Nil

Perth Metropolitan Area:

Mostly sunny.Winds easterly at 15-25 km/h.

Charts:

Figure 1.Surface synoptic chart at 00 UTC(8 AM local time today).Image courtesy of the Australian Bureau of Meteorology(BOM). 

Figure 3.Key features identified on True Colour RGB satellite image at around 06:00 UTC(2 PM local time today).Satellite image courtesy of the Japanese Meteorological Agency(JMA).

Figure 3.Mean Sea Level Pressure(MSLP) analysis with infrared greyscale satellite image at 00 UTC(8 AM 
local time today).Image courtesy of the Australian Bureau of Meteorology(BOM).

Figure 4:Surface synoptic prognosis.Image courtesy of the Australian Bureau of Meteorology(BOM)
Some data on this site is sourced from the Australian Bureau of Meteorology(BOM).