Weather forecast for Perth effective as of 9:00 PM Saturday July 14

Weather forecast for Perth effective as of 9:00 PM Saturday July 14
Explanatory notes:
Scroll down below this section for forecast. 

Figure 1.Surface synoptic chart at 12 UTC(8 PM local time yesterday).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 yesterday).Satellite image courtesy of the Japanese Meteorological Agency(JMA).

Figure 4.Mean Sea Level Pressure(MSLP) analysis with infrared greyscale satellite image at 12 UTC(8 PM 
local time yesterday).Image courtesy of the Australian Bureau of Meteorology(BOM).

Figure 4:Surface synoptic prognosis.Image courtesy of the Australian Bureau of Meteorology(BOM).

Deep cold air mass leads to showers and isolated thunderstorms.

Cold frontal passage occurred this evening bringing showers and also thunderstorms with instability.Gusty winds occurred ahead of the thunderstorms with a peak wind gusts of 104 km/h recorded at Melville Waters at 5:52 PM 

Plenty of showers on Sunday and Monday with a cold and unstable west-southwesterly air stream.

Whether Tuesday and Wednesday are also showery depends on whether the high pressure ridge lies to the north or over the region.

Another cold frontal passage is likely late on Friday/early on Saturday.

The rest of Saturday July 14:

City:

Showers.Possible thunderstorms.

Chance of any rain:95%

Perth metropolitan area:

Partly to mostly cloudy.A very high(95%) chance of showers.The chance of thunderstorms and/or small hail.Winds southwesterly at 25-40 km/h over near the coast grading to light winds inland.Wind gusts in excess of 60 km/h possible.

Sunday July 15:

City:

7-18 Degrees Celsius

Showers.

Chance of any rain:90%

Amount:1 to 3 mm.

Perth metropolitan area:

Mostly cloudy.A very high(90%) chance of showers.Winds west-southwesterly at 15-25 km/h.

Monday July 16:

City:

11-19 Degrees Celsius

Showers.

Chance of any rain:95%

Amount:2 to 4 mm.

Perth metropolitan area:

Mostly cloudy.A very high(95%) chance of showers.Winds west-southwesterly at 20-30 km/h becoming light at night.

Tuesday July 17:

City:

6-18 Degrees Celsius

Possible shower.

Chance of any rain:30%

Amount:0 to 1 mm.

Perth metropolitan area:

Partly to mostly cloudy.A slight(30%) chance of showers.Light winds becoming west-northwesterly at 15-25 km/h from late morning becoming westerly at 10-20 km/h at night.

Wednesday July 18:

City:

9-19 Degrees Celsius

Showers.

Chance of any rain:80%

Amount:0.4 to 2 mm.

Perth metropolitan area:

Partly to mostly cloudy.A high(80%) chance of showers.Winds west-southwesterly at 10-20 km/h.

Thursday July 19:

City:

6-19 Degrees Celsius

Partly cloudy.

Chance of any rain:20%

Amount:0 mm.

Perth metropolitan area:

Partly cloudy.A slight(20%) chance of showers.Light winds.

Friday July 19:

City:

7-21 Degrees Celsius

PM showers.

Chance of any rain:70%

Amount:1 to 6 mm.

Perth metropolitan area:

Mostly sunny morning.A high(70%) chance of showers from afternoon.The chance of a thunderstorm at night.Winds northwesterly at 20-30 km/h becoming westerly at night.

Saturday July 20:

City:

12-18 Degrees Celsius

Showers.

Chance of any rain:90%

Amount:4 to 10 mm.

Perth metropolitan area:

Mostly sunny morning.A very high(90%) chance of showers from afternoon.The chance of a thunderstorm in the morning.Winds west-northwesterly at 15-25 km/h.

Forecast for today produced at 12:00 AM,forecast for the rest of the days produced at 4:20 PM Wednesday July 11.Weather icons courtesy of the US National Weather Service.