NATIONAL WEATHER PICTURE - SUNDAY 18TH OF JULY 2021

Headlines


  • Showers about parts of southern parts of the nation, with cloudy skies, but the inland has turned dry.

  • The north still hot with above average temperatures as a dry southeasterly surge continues to move north.

  • More rainfall coming back for the southern third of the nation while the dry continues over the north.

National Satellite Picture - Sunday 18th of July 2021

A fairly settled satellite today after all that wild weather over the past week. Conditions taking a breather with low cloud and light showers continuing for southern parts of SA, VIC and western TAS. Skies mostly dry and partly cloudy over the eastern inland though winds have dropped out. Showers over WA, some moderate with thick high cloud over parts of the SWLD not producing much rainfall at this stage. Dry and clear elsewhere.

Areas to watch this week.

First area of interest in red will bring that soaking rainfall through the southwest and into SA during early to mid week as the low weakens through Australia. The next wave of moisture is up north of the NT and that will drift west into the Indian Ocean and could be lifted into areas of rainfall as a trough and strong cold front approach during the latter parts of this week.

Temperatures - Sunday 18th of July 2021

Temperatures are relatively seasonal through the south after a very cold day on Saturday. Plenty of sunshine under a weak ridge over SA leading to a much better day of weather. Warm over the central and southern parts of the NT and WA with more sunshine and lighter winds. Though up north it is hot and dry with temperatures above average. In the eastern inland, temperatures have reduced since yesterday with colder air filtering in.

Seasonal temperatures for mid July throughout the southeast with gloomy skies over the southern coastline grading to partly cloudy inland and clear through parts of northern SA and southern QLD.

Radar - Sunday 18th of July 2021

A few light showers and areas of drizzle in a stabalising northwest to westerly flow as high pressure moves through central Australia. The rainfall activity expected to remains largely unchanged for the region Monday with coastal light showers to continue.

Rainfall for the next 10 days - Sunday 18th of July 2021


00z GFS Rainfall for the next 10 days - Sunday 18th of July 2021

Rainfall totals have bounced a bit this evening in GFS as it still struggles to pin down the rainfall spread coming through with the frontal activity but how much moisture does it absorb as each feature comes across this week. Early in the week there will be rainfall over the southern coastal areas, before that increases over the southeast and southwest during Tuesday before rainfall moves out of the southeast, moves into the SA from WA and then a stronger system develops later this week which again has a severe weather look to it.

00z Euro Rainfall for the next 10 days - Sunday 18th of July 2021

Rainfall a little lighter than the other models this evening, however this is due to the major system that GFS/CMC have for later in the outlook being less intense. But again the winter westerly profile will dominate the rainfall spread for the coming 10 days and that is very good agreement. But we will be looking at each system as they come through this week.

00z CMC Rainfall for the next 10 days - Sunday 18th of July 2021

Rainfall largely unchanged from this morning, but I do note the similar rainfall spread as per the GFS which is good for forecasting, but rainfall totals are hard to pin down throughout the week. So looking at each system with greater detail will be easier this week than lumping it all together.


Model discussion and analysis


00z GFS Upper Air Pattern and about 18000ft - Sunday 18th of July 2021

A vigorous upper flow pattern continues for the coming 10 days at least but beyond there into the medium term, the weather remains quite active with gusty conditions and colder weather looming for southern areas as we track into August. The north, the same old song and dance with an upper high in full control and that will remain in place to continue the warmer than normal days and seasonal sunshine and dry air.

00z GFS Surface Pressure Pattern and Rainfall - Sunday 18th of July 2021

A cold front will begin to emerge out of the southern ocean during Monday and race through SA, VIC, TAS and NSW during Tuesday and this system continues to hook into better moisture so showers may be more widespread than what is being advertised in forecasts elsewhere, so keep watch for follow up moderate rainfall. The airmass looks cold so another round farmers and graziers warnings should be issued. The southwest will see a burst of rainfall from the land falling low pressure, which now looks to become absorbed into the westerly low extending the moderate rainfall from that feature into SA on Wednesday night and Thursday and then the southeast states Friday ahead of strong cold fronts that may bring heavy snowfalls down to low levels, widespread moderate rainfall, gales and very cold weather. The west will also widespread showers with follow up cold fronts. This whole sequence the north is dry and hot under the dome of the upper ridge.

00z Euro Surface Pressure Pattern and Rainfall - Sunday 18th of July 2021

The Euro continues in the same frame as the GFS for this week, with a front coming through the southeast Tuesday. A low pressure system will then roll through the west of the nation with widespread rainfall. Then that low comes into SA and weakens into the western inland of NSW. That is as another strong cold front comes through southwest WA and that system likely to bring a burst of gales and showery weather to much of the southeast. I am of the belief that this system could be a severe weather event for the east and southeast

00z Euro Precipitable Water Values - Sunday 18th of July 2021

PW Values remain fairly high over the course of the coming 10 days with the jet stream drawing that into frontal weather bringing bursts of rainfall and cloudy skies The rest of the north under the stable influence of an upper high which means that even though the PW Values are elevated, the cloud will suppressed and unproductive through northern areas. The system at the end of the run, could produce more inland rainfall for WA, SA and the southern parts of the NT.

More analysis to come in the state by state look at the week ahead.

12 views0 comments