SA SITS IN BETWEEN ALL THE SYSTEMS - BUT OUR TIME IS COMING! RAIN RETURNS FOR THE SOUTHEAST SUNDAY.

The wait continues but as I pointed out this morning, the moisture is pooling in the right locations for rainfall to increase in chances and coverage during the coming week or two, it will be a slow increase, but once the long wave trough comes east, it will send through fronts bringing windy wet weather.


The timing of that still looks likely from Sunday onwards, with the southeast districts getting the best of it first, before the rainfall chances migrate slowly northwards with each front that comes across.


GFS 00z run - 500mb flow pattern at 18000ft above our heads.

Showing the more aggressive fast flow pattern above our heads from later in the weekend into next week.

GFS 00z run - Surface pressure pattern and rainfall distribution that correlates to the upper flow pattern. This will continuing to change.


You may have seen this morning that the moisture did link up with a cold front and a low pressure system to bring in a large scale rainfall event later in the period, as expected that has disappeared but it will likely return in some form through this week with a better handle on systems impacting our region later this week into the weekend.


GFS 18Z - Surface Pressure Pattern and Rainfall - Valid Monday 5th of July 2021.

Great example when the front and moisture is in phase and the outcome can be quite decent! This idea is still on the table even though models are not showing it tonight.

Korean Model - 12z run - Rainfall for the next 12 days - Valid Monday 5th of July 2021.

Showing that moisture pooling just outside of the 10 day window, with the long wave trough moving through to Central parts of the nation. So again it may look crappy out there in terms of rainfall but that is not the way to view it, deterministic modelling is not useful and the ensembles are wetter in line with the climatic drivers. I will have more on that tomorrow and focus on the deterministic data tonight.

Euro 00z Rainfall for SA - Next 10 days - Valid Monday 5th of July 2021.

I do think this model is a little too dry for the state and will incorporate more rainfall as we go through the week, especially for next week with an active wavy flow.

And a look at the model with SE SA -which gets chopped off the charts often.

The rainfall for this part of the world is much more generous as it is exposed to that westerly wind regime. The power of the ocean! Once the winds turn more southwesterly through SA as the long wave passes through, then rainfall will increase for southern parts of the state including the Ag areas - this likely to happen from mid next week.


In the meantime the weather is benign, cold starts, sunny days with areas of high cloud (as per today) floating through with no rainfall.


Rainfall for the next 10 days - Valid Monday 5th of July 2021.

Rainfall for the next 10 days - Valid Monday 5th of July 2021.

So I will leave it at that, it is just a waiting game but I do think the rainfall signals will improve as we go through the week.


It is looking cold next week however with widespread below average temperatures expected to develop over the region with high wind chill. This could provide headaches for farmers throughout the region with large amounts of stock with the prolonged windy wintry period.


Temperature Anomalies Forecast - July 12-19th 2021.

Need more weather forecasts and information? Email me at karllijnders@weathermatters.org to find out about tailored forecasting.


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