NATIONAL WEATHER PICTURE - PM EDITION - FRIDAY 9TH OF JULY 2021

Headlines


  • Rain clearing out of eastern inland NSW and QLD with a drier airmass moving in. Rain persists about parts of the NSW coast with a low developing offshore and deepening overnight into Saturday.

  • Surprise showers over parts of SA with colder air passing through, clearing tonight with more rainfall and windy weather developing from Sunday.

  • Rain and storms passing through southwest WA this afternoon with a moderate cold front. Some heavy falls have already been observed this afternoon.

  • Heating up over the Top End and northern WA, with above average temperatures thanks to an upper high.


National Satellite Picture - Valid Friday 9th of July 2021.

Active weather day across the nation with a large scale trough and developing low over the east with widespread cloud. A large cold front of moderate strength producing widespread cloud over the southwest. A weakening cold front south of SA has had enough energy to squeeze out a few showers this afternoon over the Southeast of SA. Otherwise it is dry through the north.

Significant cloud cover developed over the east overnight and produced widespread rainfall. The rainfall easing from west to east over the inland as the low develops and deepens off the coast, sending dry air over the rain impacted areas. Rain increasing along the coast this evening from Sydney northwards to Forster with moderate to heavy falls possible.

Weak upper trough attached to a weakening cold front south of SA has kicked off a few showers this afternoon with some OK totals if you got under one of them. They will simmer down with the sun setting this evening.

Out west, a strong cold front is approaching and has started to cross through most of the west coast this afternoon and has brought widespread rainfall and scattered thunderstorms as forecast. Moderate falls have also been observed. Cold air to follow will bring the wintry elements overnight as that rolls through the southwest.

Temperatures - Valid Friday 9th of July 2021.

Seasonally warm over the north this afternoon but values right within tolerance. The mid sections of the country about seasonal. Cooler over the southeast with a low passing over, that low has kept temperatures under 10C across the Tablelands. Fine weather elsewhere with sunny skies boosting the afternoon comfort levels.

Can make out where it is cloudy and raining this afternoon with some single figure temperatures over the Tablelands. Warmer back in the west and through to SA with where the sun has been out and drier air is in place.

Cold front offshore WA will send temperatures downward this afternoon and overnight with a cold and blustery westerly wind keeping things fresh. Passing showers with small hail also going to make it feel a lot colder during Saturday but it improves by Sunday ahead of the next front.

Radar - Valid Friday 9th of July 2021.

Strong cold front coming into the Perth metro with widespread showers and thunderstorms. By the time you see this, the front will be through Perth and heading over the SWLD with moderate falls and a colder change. Rainfall rates have been quite heavy at times with thunderstorms today. Showers to follow the main rain band with thunderstorms and hail about the coast.

Clumps of showers over the Adelaide Metro and Gulf region today have produced isolated falls up to 5mm. The showers should decrease this evening. More wet weather comes back on Sunday afternoon.

Widespread rainfall contracting out of the inland with a low pressure system forming offshore the Central Coast. Moderate falls have been observed today after heavy rainfall last night with moderate to heavy rainfall possible along the coast overnight into Saturday with gusty southerly winds.

Rainfall for the next 10 days - Valid Friday 9th of July 2021.

Rainfall clears out of the east coast during Saturday. Rain builds over southern parts of the nation during Sunday but increases during Tuesday onwards with moderate falls extending to the western inland with a strong front. More frontal weather Thursday and a major front next Friday brings follow up rainfall for SA, VIC, NSW and TAS. The west dries out later in the period ahead of a major northwest cloud band that builds offshore later in the run.


00z GFS Rainfall - Next 10 days - Valid Friday 9th of July 2021.

The signals continue for the rainfall focus shifting to southern parts of the nation, with the rain still heavy over the coming 10 days for the southwest of WA. The rain clears the east coast but returns to the western inland of NSW, creeping into far southern QLD. Wet through SA and VIC/TAS right through next week, with the rainfall increasing in intensity from Tuesday onwards with the approach of the long wave trough. Northwest cloud band potential exists in the day 9-10 window and after this period, see below in the discussion

00z Euro Rainfall - Next 10 days - Valid Friday 9th of July 2021.

Rainfall leaves the east and then the coastal areas mostly dry. Rainfall then is focused through southern parts of the nation with fast moving cold fronts. Heavy falls continue for the southwest of WA, developing through SA mid to late next week and over the eastern inland of NSW during mid next week with a trough. The moisture in the Northwest Indian Ocean is also there. Note, falls will be heavier over western Tasmania than what models are expressing due to topography.

00z CMC Rainfall - Next 10 days - Valid Friday 9th of July 2021.

Similar rainfall structure to GFS with rainfall leaving the east coast, and developing over southern parts of the nation with frontal weather developing from Tuesday. Rainfall returns to the western inland of NSW Tuesday with moderate falls over the ranges and points west. Then a northwest cloudband developing later in the period.


Model Discussion and Analysis - Valid Friday 9th of July 2021.


00z GFS Upper flow pattern at 500mb/18000ft

00z GFS Surface pressure pattern with rainfall


Saturday 10th of July 2021

Upper low lifts off the east coast with an upper ridge passing through SA into the eastern inland with clearing conditions. A strong long wave passing through the southwest moving rapidly eastwards. Upper high nosing in from the Coral Sea sending temperatures above the average.

High pressure moving into the southeast inland with clearing skies and lighter winds, the weekend starting out settled. Along the east coast, rain in the morning tending to showers during the day before easing later. Some moderate falls between Sydney and Forster. The low moving eastwards. Fine weather over the north with increasing temperatures. Cold air following a cold front brings showers and strong winds early in the day for the southwest, easing later. The second chart shows how quickly the pattern evolves through the day.

Sunday 11th of July 2021

High pressure moves into the southeast and clears off the low pressure to the east. Drier weather for much of the east. That drier picture moves over the northern half of the nation with well above average temperatures. A new ridge over WA will keep skies clear and kick the cold front over the Bight with upper cold pool moving east. Cloud increases over southeast SA with showers developing later.

Monday 12th of July 2021

Partly cloudy in the east with onshore winds as high pressure moves southeast of NSW during the day. Cold front weakening over the southeast and slowing down with scattered showers persisting over the southeast districts and then contracting into southwest Victoria. Light to moderate falls at best. Widespread rain developing over the west coast of WA with another strong front approaching with the next wave of wintry weather.

Tuesday 13th of July 2021

Deep low pressure area with multiple centres over the southwest of WA bringing windy and showery weather to the region. High pressure over the southeast and east seeing showers early in the day become isolated and clear in a northwest to northerly flow. The day will be mild to warm over the southeast following the front. Fine and mild over NSW and QLD with a northerly flow. Fine over the north with above average temperatures.

Wednesday 14th of July 2021

Front moves from WA into SA overnight Tuesday into Wednesday with a band of rain. That rain races through to the eastern inland of NSW and southern QLD later Wednesday with light to moderate falls mainly, west of the divide. Rain will be more extensive over the northern slopes of VIC and through the southeast of NSW on the western side of the divide, up to the west of Canberra. Another front will bring showers and windy weather to southern SA through the day. Another weak front keeps the showers going over southwest WA.

Thursday 15th of July 2021

Rain continues on and west of the divide through NSW into northeast VIC with a trough pushing through. A weak ridge over Central Australia will clear the skies over the inland later. Another front moving through southeast SA into western VIC with light to moderate rainfall persisting. A strong cold front with a severe weather look brings wild wintry weather to the SWLD during the day. The heat continues over the north.

Friday 16th of July 2021

Very strong front passing through the Bight bringing wild weather to the coastal areas of WA into SA. A downstream trough will keep showers going through southeast SA, southwest VIC and along the northern slopes in VIC in unstable northwest to westerly winds. Fine weather returns to inland NSW and QLD under a weak ridge. Above average temperatures continue for northern parts of the nation.

Strong cold front arrives later in the day through southeast SA with a band of rain with moderate falls. A pre frontal trough could also trigger a few storms ahead of the main rainfall through VIC and NSW. Upper ridge, weak, over QLD will maintain fine weather. A fast moving ridge clears southwest WA.

Saturday 17th of July 2021

The signals for the weekend over the southeast is bitterly cold and wintry with widespread showers and gusty conditions. Moderate falls are possible if the low develops closer to the coast with heavy snowfalls possible over the Alpine areas with the low and cold air combining to produce widespread wintry precipitation. Fine elsewhere with well above average temperatures over the north and temperatures coming down over the eastern inland.

Sunday 18th of July 2021.

Showery through the southeast with local hail and thunder contracting east through VIC. Showers easing through SA and drying out by the end of the day. Fine weather over the eastern inland of QLD, though a few showers and cold weather will be found over inland NSW from Orange south to VIC. A large tropical moisture plume offshore WA will see cloud increase there in a warmer northeasterly flow.

Monday 19th of July 2021.

That moisture arrives the day after and this will be the system to watch while dealing with the frontal weather over southern Australia.

Tuesday 20th of July 2021.

And there is the northwest cloud band. So again this will continue to chop and change but the signal that has been off outside of the medium term is now edging into short term forecasting. Certainly a good sign for our friends in SA and VIC needing some rainfall.

We have made the weekend and the next update for the nation from me will be during Saturday. Remember one National weather update per day on the weekends with notes for state based weather issues and then a full run through Sunday as we begin the new working week.


Happy Friday.

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