NATIONAL WEATHER PICTURE - PM EDITION - WEDNESDAY 14TH OF JULY 2021

Headlines


  • Vigorous westerly wind regime with a series of shortwave troughs triggering bursts of showers and thunderstorms over southern states during the coming 24hrs.

  • Rain, moderate to heavy at times along the divide continuing through NE VIC all the way through to extreme southern QLD.

  • The west begins to dry out as high pressure moves in.

  • Speaking of high pressure and an upper high continuing to bring well above average temperatures and humidity levels on the rise.

  • What about the model madness for the follow up rainfall next week?

Lets see if we can answer some of these if not all of the questions below.


National Satellite Picture - Valid Wednesday 14th of July 2021.

A classic winter setup across the nation with a negative IOD in place. Moisture streaming through the jet stream, on the northern periphery of the coolest air travelling over southern Australia and keeping the warmer than average temperatures passing through north of the cloud band. To the south is where the most active weather is observed, with short wave troughs and cold fronts rolling through at speed. Widespread rain under extensive cloud over NSW and northeast VIC producing moderate mountain rainfall. A strong cold front approaching WA this afternoon and evening.

A strong cold front is coming into frame now southwest of WA, this will be the front to watch if you are living through SA and VIC, southern NSW and TAS. Showers increasing this afternoon over the west and south coasts with a blustery southwest change. Some hail and thunder again possible, this time more frequent over the south coast.

Temperatures - Wednesday 14th of July 2021.

A warm day across the nation today, despite the rainfall and cloud over the southeast, even under that cloud cover it is rather warm for this time of year. Following the rain band through SA it is very mild with the coldest air sitting offshore with the troughs rolling through the westerly wind regime. These elevated temperatures could add more fuel into the weather tomorrow as a strong cold front approaches southwest WA. Mild ahead of that feature this afternoon but temperatures will plunge tonight.

This is also another big weather feature at the moment, temperatures near 37C this afternoon over parts of the Top End, a sign that we are seeing an early build up this year and the humidity values are also elevated with these temperatures. Will continue to monitor these temperatures as they will eventually spill south into August if we get broad scale northwest winds.

Radar - Wednesday 14th of July 2021.

Rainfall moderate about the west of the divide with Canberra sitting right at the point where the rainfall falls apart and the rain shadow begins, very normal in the shadow of the Brindabellas. Rain turning to snow over high ground of the ACT and NSW Alpine areas but it is a wet snow mix. Rain is increasing further north over the Central and Northern Tablelands tonight.

Rainfall for the next 10 days - Wednesday 14th of July 2021.

Rainfall stays on course for the south and east for the next few days with no major change in the guidance for the coming fronts and low pressure. The colder drier surge will move through during Friday that will kick the moisture back to the north and west of the nation. Another round of wet weather develops from early next week offshore WA with more moisture while the southeast picks up on more frontal weather. The major rainfall event for next week will develop from this time next week and has a high chance of impacting WA, SA, VIC, TAS and southern NSW with more rainfall.

00z GFS Rainfall next 10 days - Wednesday 14th of July 2021.

Rainfall continues to stay fairly strong for the eastern inland of NSW through to VIC, SA and TAS this week into the early weekend with a series of strong fronts to move through. GFS now brings back the moisture plume as per the Euro run with a band of rainfall coming through WA early next week and sweeping the southern states before follow up cold fronts brings more rainfall into the southeast, that is more plausible than this morning runs. Drier signal returns to the inland of the nation under a upper high.

00z Euro Rainfall next 10 days -Wednesday 14th of July 2021.

Coastal areas of the south to be wet and windy for the coming few days. Rain areas persist over the western side of the GDR in NSW with northwest winds and moisture continuing to combine. Heavy falls possible through southeast SA, Adelaide Hills and through elevated terrain in VIC. Euro tonight strengthening the northwest cloud band for next week with a higher chance of follow up rainfall for WA, SA and spreading into VIC and southern NSW at the end of the run.

00z CMC Rainfall next 10 days - Wednesday 14th of July 2021.

Similar to the other modelling tonight but really starting to strengthen signals for rainfall next week from northwest to southeast through the southern states. Some moderate to heavy falls expected this week over the southern states, the rain moderate to heavy at times during the next 48hrs over the GDR in NSW before the focus shifts south.

Models Discussion - (I have cut down the content and reading so it is a little easier for those on the fly)


00z GFS Upper Air Pattern next 16 days - Wednesday 14th of July 2021.

The GFS has moved back to be more in line with the Euro from this morning and that continues to support a few fronts coming through Sunday through to about Tuesday, not quite connecting with the moisture to bring widespread rainfall through WA early in the week, but it brings through a stronger system with widespread rainfall for WA this time next week, that too spreads across the country. And then it is the frontal barrage for the southern states. After that, if that system cut off into an inland low over western QLD and NSW with all the moisture about, well that would be an epic rainfall producer for large parts of the south and east, but lets just say that will be gone by the next run.

00z GFS Surface Pressure Pattern and Rainfall next 16 days - Wednesday 14th of July 2021.

Significant winter weather occurring through the southern states over the coming 72 hours with windy, showery and stormy weather. Flood watches in place for persistent rainfall over the inland of NSW and for the Lofty Ranges. Classic winter sequence. It dries out from WA during Friday then clears the southern and southeastern inland this weekend. Frontal weather looks to keep the rest of the southeast showery most days through the outlook now, with that weather set to increase from this time next week with a set of strong cold fronts passing through. The northern half of the nation remains dry and warm with settled conditions and above average temperatures.

00z GFS Precipitable Water Anomalies next 16 days - Wednesday 14th of July 2021.

Significant moisture continues to spread through the interior and over the eastern inland of NSW and southern QLD bringing more rainfall and a lot of cloud. There is a lot of moisture embedded within the westerly flow that will create more wet and windy weather over the southeast and southern states. A stronger cold front moving through WA tonight will catch up to that moisture and a larger band of rainfall likely to form through southern SA and into VIC later Thursday with storm risks. The rain moving into NSW and eastern VIC overnight into Friday. The weather will moderate on Saturday from the west, but the showers will continue for TAS and VIC. More rainfall will develop from the west next week with moderate to heavy falls possible from this time next week from WA through to southeast states later in the week.

00z Euro Surface Pressure Pattern and Rainfall next 10 days - Wednesday 14th of July 2021.

A wet phase in the winter westerly over the coming 4-5 days which has been well forecast by the Euro, with high levels of moisture, colder air racing north and a soup bowl of low pressure and troughs lifting it all to wintry rainfall. That will persist til about Sunday. More rainfall coming through WA next week while the east dries out over the inland. Then more showery weather developing for southern SA, VIC and TAS with a weak upper trough before the next major rain event moves in from WA with a high chance of inland rainfall returning with a moisture infeed.

00z Euro Precipitable Water Anomalies next 10 days - Wednesday 14th of July 2021.

And you can see the moisture plume remaining strong over the inland tonight and wrapping around the low pressure system over the southern states for the coming 2 days. Showers should be efficient rainfall producers. Then the dry surge still expected behind the cold blast on Friday. The next wave of moisture comes in from the northwest this time next week and it is looking more favourable tonight for that rainfall to impact more of the inland if it verifies.

More details in the state by state evening wraps in the next hour and of course another update on next week's rainfall spread after 930pm tonight.

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