NATIONAL WEATHER PICTURE - AM EDITION - THURSDAY 15TH OF JULY 2021

Headlines

  • A wet night over the GDR in NSW with widespread rain and moderate falls. That rainfall continues today.

  • Showers and storms rolling through SA and VIC overnight and increasing in coverage today

  • Rain and showers finally ease over WA with a high nosing in.

  • Fine and warm to hot over QLD and the NT, temperatures well above average in some locations.

  • More rainfall lurking next week with the potential for decent follow up.


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

Active westerly wind belt with multiple troughs moving through the east and southeast passing through this morning, ahead of a strong cold front that is bringing areas of rain and colder weather to southern WA and into western SA. Some thunderstorm activity has been observed across the southern coasts of WA, SA and western VIC. So starting off quiet for many southern states this morning, but the weather will shake and bake this afternoon and this evening. Elsewhere, rain increased overnight over the northern parts of NSW and extreme southern QLD with moderate falls. The rain has eased over the southeast of NSW but as mentioned things turn once again this afternoon and this evening. Dry elsewhere.

Temperatures - Thursday 15th of July 2021.

A mild morning with a warm and moist airmass passing through the northern flank of a long wave that is bringing a colder burst to WA this morning. That colder drier air will race into SA and VIC this evening. But ahead of that wave, the east should be well above average, many areas seeing the warmest weather since April. Hot over the north.

Temperatures up to 12C warmer than this time on Monday through many areas with that moisture working it's way through the westerly wind regime and the cloud cover and rain over the northern inland of NSW, keeping temperatures in double figures. Temperatures begin to fall from SA later today and the eastern inland should feel that later Friday into the weekend.

Radar - Thursday 15th of July 2021.

Showers, some thundery over the northern inland of NSW, stacking up along the western slopes. The rain should be more persistent today and through Friday rather than the drizzle that has been observed yesterday with 10-40mm still expected through this region over the coming 48hrs. The heavier falls over the GDR.

Rainfall for the next 10 days - Thursday 15th of July 2021.

Rainfall largely unchanged in guidance overnight but more of the inland will lose the falls by this afternoon with the cloud band moves by. The rainfall over the southeast states as advertised comes through Thursday to Saturday afternoon with more light showers for southern areas early next week. Meanwhile easing conditions in the west followed by another major rainfall event from mid next week with most of what is seen there falling next week.

GFS Rainfall next 10 days - Thursday 15th of July 2021.

Showers increases today and the chance of thunderstorms. That showery weather increasing Friday and Saturday for SA, VIC and southern NSW. Rain increasing over the north of NSW and southern QLD with the moisture pushing east. Showers ease for WA but returns next week with another major moisture surge coming out of the Indian Ocean setting up the next rainfall event next week for the south and east.

Euro Rainfall next 10 days - Thursday 15th of July 2021.

Very similar rainfall spread as per the GFS, with rainfall expected to be widespread over the east and south the coming 3-4 days before the weather winds down for the inland as the air stabalises. The rainfall eases in the west today and a dry weekend. More rainfall develops from the Indian Ocean next week with that traversing the southern states mid to late next week with follow up falls. Under the upper high and ridging, it is warm to hot and dry.

CMC Rainfall next 10 days - Thursday 15th of July 2021.

Good agreement in the rainfall spread over the east with the bulk of the rainfall still expected from Thursday into Saturday afternoon before the sequence eases over the inland and GDR in the east. Another wave of rainfall expected to develop from the west and northwest with a major cloud band moving over WA from early next week and spreading east this time next week.

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


GFS Upper Air Pattern next 16 days - Thursday 15th of July 2021.

We have been seeing this fast flow pattern since the website started 2 weeks ago and this is now verifying in real time. The cold airmass passes through with the final front that moves in tonight through Saturday. With the airmass stabalising with a ridge over inland areas from Saturday afternoon. Then the next set of fronts develop next week, the strongest of those fronts linking into moisture over WA with further frontal weather and moisture infeed to follow for the remainder of the month.

GFS Surface Pressure Pattern and Rainfall next 16 days Thursday 15th of July 2021.

Fast flow pattern with multiple troughs in a moist airmass brings widespread showers with thunder and hail today, some heavy falls also possible across parts of SA, VIC, TAS and NSW. This weather eases over the east during the weekend and clears over WA from Friday. Then as you can see the winter westerly hangs on from early next week with wet weather increasing for most of the southern states. Inland rainfall may increase with the passage of a strong trough and moisture plume this time next week.

GFS Precipitable Water Anomalies next 16 days Thursday 15th of July 2021.

Higher PW Values moving through to the east today with moderate rainfall resolving by Friday afternoon over the northern Tablelands. The moisture continues to rotate through the westerly wind regime allowing for widespread showers and moderate to heavy falls in a cold unstable airmass. The west dries out, but then next week, another surge of moisture moving through WA and coming eastwards into SA, VIC and NSW later next week with more rainfall events to work with for the remainder of the month.

Euro Precipitable Water Anomalies next 10 days Thursday 15th of July 2021.

Impressive moisture lifts out of the nation next this weekend, but check out the next surge coming down the pipe via the jet stream through WA. That sits in a much better orientation for rainfall to return over inland areas next week. So follow up rainfall for inland areas is likely. Showery weather for quite a bit of the coming 10 days is expected for coastal areas, the wild card is the system early next week, may bring back light to moderate rainfall back into the southern inland of NSW.

Euro Surface Pressure Pattern and Rainfall next 10 days. Thursday 15th of July 2021.

Widespread showers with the gusty westerly flow is well handled by the modelling and that will continue for the coming 3 days. The fine weather finally returns to WA from Friday into the weekend. The high moving over the central parts of the nation before setting up camp over QLD. Rotating through the moderating westerly flow will be further fronts for SA, VIC and TAS into next week. Then a major northwest cloud band developing with more moderate rainfall expected to sweep the nation next week.

So I will have the state based forecasts in the coming hour or so (have radio commitments this morning as I do these) with a look at next week's follow up rainfall event in greater detail. I will have another look at the Indian Ocean and see how it is behaving against the forecast for the coming month and more analysis today for SA, VIC and NSW with the weather breaking out this afternoon.


Busy day ahead.

23 views0 comments