Weather forecast for Perth effective as of 7:00 PM Saturday February 17

Weather forecast for Perth effective as of 7:00 PM Saturday February 17:

Explanatory notes:
Scroll down below this section for forecast. 

Figure 1.Surface synoptic chart at  06 UTC(2 PM local time today).Image courtesy of the Australian Bureau of Meteorology(BOM).

Figure 2.Key features identified on True Colour RGB satellite image at around 07:00 UTC(3 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 06 UTC(2 PM 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).

Marine layer clouds lied over the region today.

The west coast trough remains inland for the rest of  the weekend resulting in mild conditions.

Some marine layer clouds expected on Sunday too.With radiational cooling of moist low level air associated with the marine layer,the slight chance of areas of fog during the early hours most likely over the hills and foothills clearing by 8 AM.High amounts of low cloud which would suppress radiational cooling would limit the potential for fog.

The marine layer remains over the region tomorrow.

On Monday with the west coast trough inland,southerly pressure gradient "bends" with solar heating leading to strong sea breezes during the afternoon and evening.Wind gusts up to 65 km/h in the afternoon and evening.

Currently it looks like somewhat east-southeasterly pressure gradient from Tuesday,sea breezes relatively suppressed or confined to western suburbs with the east-southeasterly pressure gradient.Some clouds with bases at around the 850 hPa level with moisture from the remnants of the what would be Ex Tropical Cyclone Kelvin.

Some uncertainty on the precise synoptic conditions late next week.

The long spell with no 40+ Degree Days continues with the last 40+ Degree Day being Australia Day last year!With no 40+ Degree day within the forecast period,the next 40+ Degree Day will be at least the latest on record during summer for the Perth Metro station or if there is no 40+ Degree Day at all this summer the first since the 2001-2002 summer.

The rest of Saturday February 17:

City:

Partly cloudy.

Chance of any rain:0%

Perth metropolitan area:

Partly cloudy.Winds southwesterly at 10-20 km/h easing to 5-15 km/h at night.

Sunday February 18:

City:

18-28 Degrees Celsius

Clouds decreasing.

Chance of any rain:5%

Rainfall amount:0 mm.

Perth metropolitan area:

Partly to mostly cloudy becoming mostly sunny by late morning.The slight chance of areas of fog most likely over the hills and foothills in the early hours clearing by 8 AM.Light winds becoming southwesterly at 20-30 km/h from afternoon becoming south-southwesterly at 15-25 km/h night.

Monday February 19:

City:

18-29 Degrees Celsius

Becoming sunny.Windy between afternoon to early night.

Chance of any rain:0%

Rainfall amount:0 mm.

Perth metropolitan area:

Mostly sunny becoming sunny by around the middle of the day.Winds southerly at 15-25 km/h tending south-southwesterly at 25-40 km/h between afternoon to early night becoming south-southeasterly at 20-30 km/h at night.Wind gusts up to 65 km/h in the afternoon and evening.

Tuesday February 20:

City:

17-30 Degrees Celsius

Sunny.

Chance of any rain:0%

Rainfall amount:0 mm.

Perth metropolitan area:

Sunny.Winds south to southeasterly at 15-30 km/h.

Wednesday February 21:

City:

17-30 Degrees Celsius

Partly cloudy.

Chance of any rain:5%

Rainfall amount:0 mm.

Perth metropolitan area:

Partly cloudy.Winds east-southeasterly at 15-25 km/h.

Thursday February 22:

City:

20-31 Degrees Celsius

Partly cloudy.

Chance of any rain:10%

Rainfall amount:0 mm.

Perth metropolitan area:

Partly cloudy.Light winds becoming south-southwesterly at 15-25 km/h from afternoon easing to 10-20 km/h at night.

Friday February 23:

City:

20-31 Degrees Celsius

Partly cloudy.

Chance of any rain:10%

Rainfall amount:0 mm.

Perth metropolitan area:

Partly cloudy.Winds southeasterly to southwesterly at 15-25 km/h.

Saturday February 24:

City:

20-32 Degrees Celsius

Mostly sunny.

Chance of any rain:10%

Rainfall amount:0 mm.

Perth metropolitan area:

Mostly sunny.Winds east-southeasterly at 15-25 km/h.

Forecast produced at 7:00 PM Saturday February 17.Weather icons courtesy of the US National Weather Service.